Put Spring In Your Electric Golf Cart

All electric golf cart maintenance should start with the proper care & feeding of the batteries, checking the tightness of all cable connections and maintenance of the battery racks.  I will dwell on the batteries & electrical maintenance for a while because that is where I see the most neglect.  In the discussion below when I speak of ‘cables’, I mean the thick battery-to-battery type ‘power’ cables, not the thin ‘control’ wires.  The power cables carry a large amount of DC current (current=amperes) while the thin control wires carry just a little.  Later on in the presentation I get onto the mechanical aspects of the electric golf cart.

A little history first.  In the old days, the electric golf cart had an arrangement of mechanical and/or electrical switches coupled to a series of resistance coils (springs-as some folks call them) to regulate the speed of the car.  In 1990 or so, a far more efficient, solid state, electronic speed controller (ESC) was incorporated into the golf car.  All of the motors being regulated by these early speed switches were called ‘series wound motors’.  More on this later.

In 1995, the ‘regen’ car was born.  The motor and the regen controller were designed to work together to not only regulate the speed of the car based on pedal position but, more importantly, to regulate the downhill speed of the car as well.  No longer could you race at breakneck speed down steep hillsides.  An electronic braking program designed into the ‘regen’ controller and executed by the special ‘Sep-Ex’ motor kicked in at a certain speed to slow the car down.  In 2000, ‘regen’ controller & ‘sep-ex’ motor technology took another leap.  A speed sensing device was built into the motor and the controller took on different speed characteristics (personalities) depending on what program was installed in the controller.  This technology continues to be refined today.  In order to properly care for and maintain your electric golf cart you must be aware of what speed control system you have and the peculiarities of that system.  More on sep-ex motors and the personalities of electronic controllers later on.

When you get back to your electric golf cart one of the first things to check is;  Does the car actually run?  If it does…great!  Check the water level in the batteries to be sure the plates are covered and put the electric golf cart on charge.  Don’t fill the batteries just yet unless the low water level has left the plates exposed.  If exposed add just enough distilled water to cover them.

If the electric golf cart does not run ask yourself these questions:

Did I flip the Tow/Maintenance switch over to Run?  {If the ‘regen’ controller has been left in the Tow or Tow/Maintenance position the car will not run.  The switch must be in the Run position for the car to operate.}

Did I forget to put the Tow/Maintenance switch into the Tow/Maintenance position for the long storage?  {If you did forget, the batteries may now be too discharged to move the car, or for the charger to even come on to recharge them.}

Did I leave the battery charger plugged into the car for six months?  {With some chargers this will also discharge the battery pack in the same manner as above.  Read on.}
Is there any water in the batteries?  {The liquid inside the battery cells should at least cover the plates.}

Did the batteries freeze and perhaps burst?  {Check under the car for evidence of spilled battery acid-usually a white powdery residue is present.  Any added water will simply spill out as well.}

Has a battery cable corroded and broken off?  {Inspect & wriggle each battery cable end in turn.  A weak terminal end may not allow charging current to pass.}

Will the battery charger come on?  {Sometimes the charge, especially with older batteries, may be just too low to move the car, maybe even a low or flat tire is making things worse.  If everything else checks out OK, then try to recharge the batteries.}  Modern battery chargers (1985 on) must ‘read’ a minimum ‘cut-on’ voltage from the batteries to actually cut on and begin charging.  If the overall battery voltage is too low you must somehow get them recharged to the minimum voltage required by the charger.  On an electric golf cart with 6-volt batteries you can use a small 6-volt/12-volt auto battery charger to individually recharge each battery (or two connected batteries) for an hour or so apiece.  On a car with 8-volt batteries, connect a 12-volt charger to each individual battery, then turn the charger on for NO MORE THAN 10 minutes each.  Try to restart your regular golf car charger after each battery has been on for the 10 minute charge.  Remember, you have to get the entire battery pack up to the required voltage.  Giving a short boost to a couple of batteries is sometimes all that is needed.

Be certain the water level is sufficient in each battery and that no cables are weak or broken before proceeding.  Old battery chargers come on regardless of the battery charge or electrolyte level.  Plug them in and allow the charger to stay on till the charge is complete.  Normally the ammeter dial should go above half way to indicate the charger is actually working (just a hum from the charger does not mean it is really charging).  With very discharged batteries, the charger dial may not even move off of zero.  Be sure the water level in the battery is OK and leave the charger turned on but keep a close eye on the dial.  The ammeter needle should start to crawl up the dial, at least a little, within 15 to 20 minutes.  The needle should eventually go all the way up to around 20+ amps and then gradually fall to near zero again to indicate the charge is complete.  Keep feeling the AC & DC charger cords and plugs to be sure they are not getting too hot to touch.  Warm is OK, TOO HOT IS NOT!  Once the electric golf cart is running then you can start the procedures outlined below.

Step 1 –     Cleaning the Batteries:

You might say that batteries ‘breathe’ and when they breathe out, there can be trouble.  When golf car batteries approach full charge they begin to gas, or vent a mixture of hydro-sulphuric acid vapors and hydrogen gas.  The heavier acidic vapors fall out and settle on everything nearby, starting to corrode any unprotected metal parts.  Neutralize & rinse the batteries, racks and surrounding areas regularly.  The lighter hydrogen gas rises to the highest areas of the room in which the car is being charged.  If hydrogen gas reaches a concentration of 4% it can be explosive if ignited by a spark, or even a match lighting a cigarette.  The room in which your electric golf cart is charged should have a total air exchange rate of three (3) times per hour while the car is charging…AT LEAST!!  This is especially important if the room is attached to the house, enclosed or very small.  If it is a golf shed with dozens of charging golf cars make it 5 exchanges per hour.  After many years of experience this is the method I suggest to keep your electric golf cart & batteries in top operating condition and prevent acid damage.

a. First make sure all the batteries have sufficient water (more on this later), that the battery caps are securely in place and the car has been fully charged.  Then take a hard look at the battery support racks and battery hold down brackets & J-bolts.  Will the battery racks last another year?  Do you need to remove the batteries to repair the racks from which a battery or two is hanging at a 45 degree angle?  If so you can skip this part till the racks are fixed.  Most times it’s not so drastic but look the racks over from above and from beneath the car.  Advanced cases of corrosion are usually accompanied by a white powdery looking crystal that can be very difficult to remove.  If the following procedures do not virtually eliminate all of the corrosion, then the batteries may need to be removed for a more thorough cleaning & corrosion prevention treatment.  Sometimes you will find a clean, corrosion-free rack that has become so rusted it is about to collapse.  We have replacement racks if needed.

b. Unplug the charger and drive the car to a convenient place where you can wash the batteries & battery racks with Neutralizer and lots of water (a garden hose is OK).  Lock the hill brake.

c. If you have a ‘Regen’ electrical drive system (automatically brakes going down hill), turn the master switch under the seat  to ‘Tow’ or ‘Tow/Maintenance’.  This turns the car completely off.  Be sure to turn the switch back to the “RUN” position after the cleaning is done or the car will appear dead and not run.  If you do not have a ‘Regen’ system, then just put the Forward/Reverse (F/R) switch into the Neutral position (straight up) and turn the key to ‘OFF’.  This also turns the car off…no battery current can run to the motor.

d. We recommend that you DO NOT disconnect any terminals unless it is necessary to clean them.  Regen cars require that the ‘Tow/Maintenance’ switch be in the ‘Tow’ position and that a specific sequence of battery cable disconnect & reconnect be followed.  There is some other maintenance to do here and we will cover cables later.

e. Be sure your car is in a location where the neutralized acid water, grass and mud you are about to wash off will safely wash away.  Be sure you are NOT wearing your best pair of jeans or any other cotton clothing.  Hydrosulphuric acid just loves cotton.  It’s fond of skin too, so you might want long sleeves and gloves.  Polyester clothing resists the acid.

f. Start on one side of the electric golf cart and spray our environmentally-friendly Battery Acid Neutralizer all over the tops & terminal posts of the batteries.  Be sure to spray between the batteries, on the battery racks and the inside walls of the body panels, especially if they are metal.  Now use an old paintbrush to scour all the nooks and crannies of the battery tops and sides.  Use a little extra water if you need. Follow the directions on the bottle in applying and rinsing the Neutralizer.  This liquid will change color to signify that it is neutralizing any acid present.  Allow this to sit and work for a few moments then wash the entire compartment thoroughly with lots of water, being careful to avoid any acid splash on you.

NOTE:  Water from a garden hose with a pressure nozzle, or even a commercial pressure washer, will not hurt the electrical parts of the car.  Do not let the pressure washer beat on the vital parts but a good thorough washing is fine.  Many golf clubs wash the battery compartment out every day…this is great!  Several times a month is good, once a month is ok, and certainly at seasons end at a very minimum.  Hey, it’s your investment!

g. You can use plain water from the garden hose, which does nothing to neutralize the acid but at least it keeps excess acid from contaminating the battery cable ends & racks.  You can also use a solution of baking soda (about 2 tablespoons to 1 gallon of water) to neutralize the acid, but you may be introducing some environmentally-unfriendly side effects.  In some regulatory jurisdictions, acid & soda wash is considered hazardous waste.  Besides, bicarbonate of soda does not clean.  Drippings from improperly washed batteries will stain finished concrete surfaces and, over time, cause the surface layer to decompose and start to crumble.  This is certainly a much larger concern for clubs rather than individuals, but I have seen many fine examples in private garages too.  We offer an inexpensive, plastic backed, absorbent mat made just for golf cars. Unfortunately, I do not have any magic cures for stained or crumbling garage floors.

STEP 2   –  Maintaining the Battery Terminals:

 

WARNING 1:  For your personal safety always, always, always remove all metal rings from fingers, watchbands or bracelets from wrists and any loose hanging necklaces.  If the jewelry becomes a short circuit between batteries, it will ruin your day…not to mention that cherished family jewel! 

WARNING 2:  Eye safety is a vital concern too.  Wear eye protection!  A spark from a cigarette (NO! NO! NO!) or an inadvertent battery short, such as a dropped tool (or ring), can cause a battery to explode, spew battery acid and possibly catch fire (I know this from ‘lucky’ personal experience, thank you).  Extreme caution is required.  At best an exploding battery will put the hurt to your ears and a twitter to your heart.  Should you ever drop a wrench or other tool onto a battery top—BACK AWAY IMMEDIATELY!!!!! It’s a whole lot better, and cheaper, to replace a battery than have an Emergency Room visit.  Retrieve the tool after the smoke clears.

a. This is an excellent time to check, clean, tighten & treat all of the battery terminal connections.  Battery cable looseness, weakness, oxidation and corrosion all interfere with the flow of electricity, create excess heat and decrease the efficiency of your electric golf cart.  This looseness can occur and must be checked for anywhere the thick battery cables attach; battery to battery, at the F&R switch, at the motor, controller or old fashioned wiper contact & speed board, the resistor coils or the solenoid(s).  Loose connections create a lot of heat; look for discoloration in the cable end or on the stud and base plate to which the cable is attached.  Then perform these simple checks.

b. Firmly wriggle each cable end side-to-side and then flex up & down.  There should be no looseness or movement sideways.  If there is, the nut that secures the cable end to the battery post needs to be tightened some more.  Use an adjustable wrench to tighten the nut, clockwise, just a little.  If the cable end will not tighten, even if the nut feels tight, there may be a problem with the battery post stud.  Chronic looseness of any cable end, anywhere in the electrical system, will cause a heat buildup.  Enough heat can ‘freeze’ the nut on the battery stud making it impossible to tighten the cable end.  Over time the heat can cause the lead post to melt away from the cable end.  You can see the melted lead on the side of the post, much like melted candle wax…sometimes even a pool on the battery top…sometimes little beads of lead splatter onto the battery top, melt through the case and allow acid to jostle out as the car moves along.  Be sure the cables are tight to the post.  Don’t over tighten but they should be good and snug…no wriggle! The up & down flex motion at the cable end should not cause much flex.  The end should be rigid to the post.  The cable can flex but the metal terminal end should not.  If it does easily flex or, worse, it’s downright floppy, then you have a battery cable end about to give it up.  Fix it before it leaves you, where you least expect it!  Replace that cable or crimp on a new end.  If you intend to repair your own cables & ends, you must use a good crimping tool, quality cable and the right size cable ends (or lugs).  One of the most common problems I see on battery cable repairs is a poor crimp of the cable end onto the cable.  The crimping method is very important! If the cable is not adequately secured to the terminal end it becomes just another weak link in the electrical system of the car, subject to failure at any moment.  If this situation exists when new batteries are installed, that connection will give it up.  Guaranteed!

c. If your battery cables have the old lead ‘Banjo’ style terminals that encircle the battery post (which are just about obsolete), then follow this tip:  Remove and examine the inside of each terminal connector in turn.  The lead should be shiny and bright on both the outside of the post and inside the lead terminal.  If there is any dullness, it is beginning to oxidize and you will need to clean the lead surface, preferably with a sharp knife or battery tool, until it’s shiny and clean. There are commercial battery terminal cleaner tools and if used regularly, they can do a good job.  The sharp edged tools are usually more effective than the wire brush kind.  A tough, crusty oxidation can build up that is difficult to remove, especially after a long storage.  The wire type terminal cleaners are ok if you do this procedure several times a year, but they are largely ineffective on built up, crusted oxidation. The positive terminal of a battery seems to be the most susceptible to the oxidation and corrosion.  Lots of people think their batteries need to be replaced when they will no longer push the car the required distance.  The owners are usually very surprised to learn that the batteries are fine, but the terminals had become so corroded that current could not flow.  There’s a lot of current trying to flow to an electric golf car motor and it needs a clean circuit.

d. The type of terminal oxidation mentioned above looks fundamentally different from battery rack corrosion.  Although both are caused by the acid atmosphere in and around the batteries, rack corrosion is much more sinister.  The crust and/or cable looseness can cause the car to stop.  Corrosion eats the car frame alive.  Aluminum and steel frames alike!  Aluminum frames can handle salt air much better than steel but both are the vegetable de jour to battery acid.  This rack corrosion frequently looks like a white flakey powder buildup on aluminum or steel racks, and, in severe cases, any other metal parts in the immediate vicinity including the brake cables.  It is very tenacious and may require that the batteries be removed to adequately remedy the problem. Getting back to the battery cable ends & posts, the positive terminals generally take the brunt of the corrosion but the negative posts will corrode too.  If they are badly corroded, you will need to do some serious cleaning.  You will probably need to remove the corroded cable end from the battery, soak it in neutralizer, wire brush the metal ends and then carefully inspect them.  If the ends are ok, firmly wire brush the battery post clean, reinstall the cable on the battery and tighten the nuts securely to the battery post (are the nuts clean too?  Don’t contaminate a clean cable end with a corroded nut).  Don’t leave a cleaned battery cable end & post susceptible to future corrosion.  Oxygen is what causes the problem and a good non-conducting (dielectric) coating to a clean connection will protect for a long time. Be sure to let the terminals dry thoroughly before applying any protective coating.

CAUTION:  Some electrical systems especially ‘regen’ systems, require a certain sequence when disconnecting & reconnecting the batteries.  Be sure to put the car in the TOW position before loosening any battery terminals.  Consult your service manual. Corrosion can appear as thick yellow goop (sometimes gooey, sometimes hard), white powdery fluff or as a bluish goo.  Sometimes these different kinds are on the same terminal or post or battery rack.  This is never a good thing, as corrosion seems to beget more corrosion.  Real trouble comes when it starts to get on the frame of the car.  Wave goodbye to the battery racks and car frame in severe cases.  And it is so easy to prevent!  Just hose off those batteries and racks several times a year.  No big deal!

e. Recheck the water levels in each cell.  Take the hassle out of this task by using a Battery Filler Bottle.  Use distilled water (lead acid batteries can be damaged by certain elements found in some tap water even though it is safe to drink).  Be sure the electrolyte (water) in each battery cell is, at a minimum, above the plates (the straight lines you can see when looking straight down into the battery cell).  For regular everyday use the battery water level should be just slightly below the cell collar, or about 1″ below the top of the battery.  Be careful not to overfill the cells.  This is an extremely common mistake that results in shortened overall battery life, acid getting everywhere and it requires much more maintenance. In cold climates, when the car will be left uncharged for several months, leave the water level a little low (but above the plate tops).  This raises the specific gravity of the acid, which will help prevent freezing.  Lead acid batteries keep much better in the cold than in the heat, as long as the charge stays up.  A fully charged battery will not freeze until 60 to 70 BELOW zero, whereas a discharged battery can freeze at 20 degrees ABOVE zero.  As a battery becomes discharged, the acid turns into water by the basic chemical nature of the lead acid battery.  As the charge is restored the water turns back into acid.  A detailed description his chemical process is beyond the scope of this presentation. In the busy golf season, especially in hot climates, it is recommended to keep a close eye on the water level, especially in older batteries, and NEVER let it get below the plates. Also a dirty, acid covered battery will self discharge at a faster rate than a clean treated battery, even in cooler temperatures.  The heat of a Florida summer can cause a battery to self-discharge in as few as 30 days.  Of course freezing is not a risk but a discharged battery will sulfate, which basically means hard crystals of lead sulfate clog up the tiny sponge-like cavities of the battery plates.  The longer the state of discharge lasts the more this hard-to-dissolve crystalline structure builds up and the result is less capacity in the batteries.  It is a harmful, and costly, condition if left untended.  Adequate charging avoids this situation.

f. OK, we have washed and cleaned and inspected and tightened and neutralized. Let the car drip dry for a while and then apply some sort of protection on the battery terminals to inhibit future corrosion.  When used on a new or clean terminal, proper protection can last for years with little care.  If the terminals are corroded, treatment does little but add to the mess.  Don’t believe the claims that a little spray here and there takes care of badly corroded batteries.  Clean them thoroughly with a neutralizer.  After they dry put a protective coating on the terminals.  If the batteries are fully charged, you can run the car.  If not, put the car on charge and allow the charger to run its full course.  It will take 10 or so charge/discharge cycles to bring the batteries up to full capacity after a long layover.

g. After the charge is done, unplug the charger from the car and from the wall.  If you have a ‘ReGen’ model electric (1995 and newer), be sure to turn the switch under the seat from ‘Tow’ or ‘Tow/Maintenance’ to the ‘RUN’ position.  This electrically reactivates the car for use after off-season storage. This is a very important step when preparing the car for seasonal use.  If left in the ‘TOW’ or ‘Tow Maintenance’ mode, the electronic speed controller stays dormant and will not permit the car to move.  Conversely, if the ‘TOW’ switch has been left in the ‘RUN’ mode, then the controller capacitors stay energized by drawing off the limited battery juice.  This can run the battery voltage below the critical charger ‘cut-on’ voltage leaving open the possibility of excessive lead sulfate buildup on the plates and the batteries freezing if the temperature drops too low.

STEP 3  –   Motors, Speed Controllers, and
Forward and Reverse Switches
:

DC motors that power electric vehicles must have some way of stepping down all that battery power so the driver can go slow.  High speed is no big deal…throw the juice to the motor and away you go.  Anyone with an older style ‘resistor’ car that has had a broken resistor coil has experienced this.  Step on the pedal and suddenly the car jerks to a high speed start throwing the riders back in their seats and away they go…look out!!  The days of resistor-style speed systems are passing.  The newer electronic speed controllers provide a smooth, steady pedal control at any speed.  Electric golf carts also must have a way of changing direction.  The older forward & reverse switches are mechanical devices that change the way the electricity goes through the motor.

The modern ‘regen’ cars have a special motor, called a ‘Sep-Ex’ motor that allows for the F&R switching to be electronically controlled by the ‘regen’ speed controller and a small 3-position toggle switch.  More on all this just a bit later.  Motors, speed control systems and forward/reverse switches are all closely related, interconnected and they come in various configurations.  I will present them all as best I can.

Electric golf carts made before 1990 have various, but similar methods to control low speed and the forward/reverse function.  All of the early speed control systems incorporated a series of resistor coils (springs, as I hear them referred to and, indeed, they do look like springs) to step down the voltage to the motor and thus make it turn slow.  All of the resistor coils are in the power circuit when the pedal is first pushed down.  As the pedal is depressed further, the first coil (or portion of the coil) is dropped out of the power circuit thus reducing the resistance and allowing more voltage to the motor (often this coil is the long skinny coil).  The result is more speed.  Push the pedal down even more and another resistor coil drops out (or portion thereof-Yamaha & Pargo)…more speed still.  When the pedal is to the metal all of the resistor coils are out (or should be out) of the power circuit and the motor gets all of the available battery voltage…top speed!  If any of the resistor coils have loose cable connections or physically break, the violent, uncontrolled acceleration I mentioned above will occur.  This condition will cause the speed control contacts  on a wiper style speed board to start burning and arcing and melting AND FAR WORSE, CAN CAUSE THE ACCELERATOR PEDAL TO STICK IN THE HIGH SPEED ‘RUNAWAY’ POSITION–DO NOT LET THIS HAPPEN TO YOU!!  I could tell horror stories.  To repair only the speed board & wiper contact is fruitless. The resistor coils must be intact and properly tightened as well as the speed board contacts and cables.  The odd thing about the wiper style speed board is that looseness of power cables anywhere in the system seems to cause burning and arcing at the wiper/stationary contact interface.  It will not cause the burning or the jerky, violent acceleration that broken resistor coils will cause.  Nonetheless the contact board itself will start to deteriorate due to the heat buildup and this can lead to poor wiper contact action.

CAUTION:  If the accelerator pedal up & down action starts to feel or sound rough or segmented (you can actually hear it & feel it in the pedal) rather than smooth & quiet, there is some looseness developing in the speed control system.  If the pedal is EVER sticky and doesn’t return properly & immediately upon pedal release, then you have a pedal return spring problem, possible resistor coil problems or a deteriorating speed board.  Check it out…pronto!  The speed board contacts should have a flat smooth face and be tightly attached to the contact board.  The wiper contact should be at a 90 degree angle to the stationary contacts on the board and the contact interface should be flat.  If the wiper contact is skewed or off at some funky looking angle, you have concerns.  If the wiper contact wears out or has partially burned away or looks like it has been too hot (look for partial melting), then replacement may be at hand.

OLDER SPEED CONTROLS:  Overview:  There have been various methods of controlling the way the battery voltage actually gets to the resistor coils.  Some companies used a mysterious array of solenoids and others employed a contact board with a wiper contact that sweeps over stationary contacts attached to the board (I was referring to this in the above paragraph).  Both systems are very effective and, if properly maintained, will do a very fine job of safely controlling low speed but there are problems associated with either one of these methods.  One is the resistor coils burn up battery juice so they are pretty inefficient.  The other is you cannot operate at low speed for very long.  The car should get to high speed as quickly and as safely as possible.  The battery pack provides a lot of amps that run through the electrical system and all those amps create a lot of heat at the wiper board contacts, the F&R switch, the solenoid and at the resistor array.  It requires constant maintenance to keep it in top operating condition.  As long as these systems have served the industry, these shortcomings, and the advent of solid state electronic technology, sounded the death knell of mechanical resistor based speed control methods.

The multi-solenoid speed control systems common to Club Car, Pargo, some Harley & Columbia ParCar models and many others, overcome some of the burning and arcing issues because the high current switching occurs inside the solenoids.  Of course they still use the resistor coils and if the coils break the car will violently jerk to a start.  Because of the variety and subtle differences of the multi-solenoid speed control systems I will not explain each system in depth.  Some multi-solenoid systems use a speed board as described above but the extremely high current does not go through the board.  The wiper & board contacts are part of the ‘control circuit’ and simply direct where the high current goes by turning solenoids on or off at appropriate times during the pedal travel.

Other companies, such as Club Car & later Pargo electric golfcarts, used a series of small ‘micro switches’ connected to the accelerator pedal to turn the appropriate solenoid on or off at the right time.  The early Club Cars had a ‘master solenoid’ on the extreme driver side of the solenoid array, located just behind the batteries.  The ‘master’, which looks exactly like the others, is the very first solenoid to cut on.  If this solenoid fails so goes the whole car, as the other four speed solenoids will not function if the ‘master’ does not.  As the pedal is depressed another microswitch (at the pedal) activates the next solenoid (1st speed), allowing the battery current to run through all of the resistor coils.  When the next micro & solenoid is turned on (2nd speed), the first solenoid & resistor drop out of the power circuit and now the car is moving faster (less resistance).  This process continues until all resistors are out and just the very passenger side solenoid is engaged, providing full battery juice to the motor.  If a thick carpet is under the acc pedal it can prevent the last solenoid from engaging.  If any solenoid (except the master) fails to throw (or conduct electricity through it) then that particular speed is skipped over and the astute driver will feel a little jerky sensation (the best way to feel this is on a slight incline).  If the high speed solenoid does not activate then the car seems slow and in fact it is.

Don’t be fooled by a solenoid that sounds as though it has clicked, or cut on.  Solenoids are the most common failure in any resistor controlled car and just because they throw (or click) does not mean that they are actually conducting electricity through them.  Each of the micro switches also must work in order that the associated speed solenoid works.  Club Car accelerator micros make a low volume clicking noise when they are working properly and if you listen closely you can hear them.  Put the car in neutral, leave the brake off & chock the wheels, put your head down near the accelerator pedal and slowly push the pedal all the way to the floor.  The first click should occur near the full pedal-up position.  As the pedal is depressed each of the five clicks (Club Cars before 1981 have four clicks) can be heard.  Remember that carpet on the floor?  If it is too thick the 5th click will be missing…get that carpet out of there!  The other manufacturer’s systems are fairly similar to the one just described.

Harley electric golf carts used a complicated arrangement of solenoids, large diodes and, early on, a glass enclosed ‘delay tube’ to change the battery voltage from 18-volts for low speed (two banks of 3 batteries each) over to 36-volts for high speed (one bank of 6 batteries).  I am not going there today.  Buy a manual if you have to troubleshoot this Harley system.  Club Car and others used a mechanical rotary-style F&R switch but some, such as Pargo & Harley, used a multi-solenoid F&R switching system, in addition to a multi-solenoid speed controller.  That is next.

OLDER FOWARD/REVERSE SWITCHING: To make an electric motor change its spin direction is a simple matter; change the direction the electricity flows through motor.  For instance, instead of coming into the F1 motor terminal & then out the F2 terminal,  just make it go in the F2 and out the F1.  Simple huh?  Not once you start to study the various systems the manufacturers have used over the years.  Some use a confusing array of single throw solenoids, others use one or two double-throw solenoids, still others use what appears to be a simple rotating switch.  The modern ‘regen’ motor controllers use a 3-position toggle switch but the controller actually changes the direction of the electric flow–more about these modern systems in a bit.  The older mechanical F&R switching devices, be they solenoids or a rotating switch, must be clean, the cables & terminal studs must be tight and have no signs of extreme heat buildup such as discoloration, rust or melting.  I will consider the systems separately.

Solenoid-type F&R switching requires a way to activate the appropriate solenoid(s) and most commonly this is a 3-position key switch; Reverse-Off-Forward.  The key switch itself does not carry a lot of current.  It is part of the control circuit and it provides electricity to the small terminals on a particular solenoid so it will throw & conduct the high amp current (through it’s large copper side terminals) to the motor.  The ‘solenoid’ activated may be a couple of single-throw solenoids (2 small, 2 large terminals) tied together, or one double-throw solenoid (2 small, 4 large terminals).  Pargo golf cars employ four F&R switching solenoids, two for forward & two for reverse.  Earlier Yamaha electrics and many Harleys use a pair of double-throw solenoids.  This type of F&R switching looks, and can be, intimidating to troubleshoot & repair.   The thing to keep in mind is all the solenoids work together electrically, whether they activate or not, so all must  be in good working order.  Remember too, solenoids will throw and not work, and they will work one time and not the next and then work again.  The large copper studs of each solenoid should be firmly attached to the body of the solenoid (inner nut), and the cables or any buss bars tight to the inner nut.  A buss bar is a flat copper or aluminum strip that connects the large terminals on two or more different solenoids.

Club Car,  E-Z-GO and later Yamaha models all have used a rotary type of switch to control the F&R function.  This type of switch has a base plate with four large copper contacts fixed to it and a rotating cam with four contacts.  Power cables from the motor and from either a battery or from a solenoid terminal are connected to the four stationary contacts on the F&R base plate.  Two different pairs of contacts on the rotating cam are connected by a short bussbar.  When the cam is rotated to the forward position, the ‘forward power circuit’ is connected.  When the cam rotates 90 degrees to the reverse position, then the ‘reverse power circuit’ is enabled.   The same maintenance procedures should be performed here as mentioned before; no signs of cable looseness, no signs of heat buildup or discoloration of the terminals.  The contact faces should be smooth and free of burning and pitting.  If the cam gets too hard to shift comforably, the entire switch can be disassembled, cleaned & lubed and reassembled.  Sometimes a little spray lube directed at the pivot bolt will free it up a lot.

MOTORS:  An Overview:  Golf cart motors are pretty simple things.  There is a heavy cylindical motor case with four stationary ‘field’ coils & poles attached to the inside wall.  Inside the field coils sits an ‘armature’, which spins at a very high rate of speed.  On one end of this armature is the a series of copper bars called the ‘commutator’.  The motor end cap on the commutator end holds a ball bearing, four brushes & the brush rigging.  The four spring-loaded brushes are positioned such that they ride against the commutator surface while the motor is spinning.  Indeed, they are integral to the motor working properly.  Almost all golf car motors have four large brass terminal studs sticking through the frame; the two ‘armature’ terminals labeled ‘A1’ & ‘A2’, and the two ‘field’ terminals.  The field terminals may be labeled ‘F1’ or ‘S1’ and ‘F2’ or ‘S2’.  Don’t ask me why this is so…I have no clue, but it does make it a lot more difficult to write about.  It does seem the more modern designation is ‘S’ and the older to be ‘F’–either way they mean the same thing.  Earlier motors had an end cap with a ball bearing on both ends of the motor.  Modern motors are what I call a 3/4 (three quarter) motor; only the armature end of the motor has a cap & bearing and the other end is open when the motor is out of the car.  When bolted up to the differential bell housing, the open end slips over the differential input shaft.  The input shaft centers the loose end of the armature relative to the motor frame so it can spin at high speeds.

In the old days almost all golf car motors were of a ‘series’ design.  In other words, the same amount of current ran through the stationary field as ran through the spinning armature, and the armature & field windings were just about the same size, the thickness of a thin pencil.  You couldn’t really do anything fancy with a series motor but in 1995 the industry introduced a ‘Sep-Ex’ motor, or a ‘regen’ motor as I commonly call it.  ‘Sep-Ex’ means ‘separately-excited’, and the term refers to being able to feed the motor ‘field’ a different amount of current (say, 20 amps) from what is being fed to the motor ‘armature’ (say, 300 amps).  These variable field functions are performed by a solid state, electronic ‘regen’ speed controller that is designed specifically for the motor.  Also, the ‘sep-ex’ motor is fundumentally different from the older series wound motors.  The armature windings of the sep-ex motor are similar to the series motor but the sep-ex field windings are very fine, more like the thin lead of a mechanical pencil–3 to 5mm thick.  Because of the fine windings in the field and the ability to vary the field strength, all kinds of fancy things can be done with a sep-ex motor.  The car can have faster or slower acceleration and top speed, the downhill speed can be preset, roll-away protection is available and lots of other cool things.  But the motor needs a regen speed controller for it to function properly.   The component parts, like the solenoid, the accelerator pedal-position sensor (tells the controller how fast to spin the motor), the speed sensor in the motor (tells the controller how fast the motor is spinning), the reverse buzzer all need to be working & in good order, and there must be good clean tight connections at the speed controller and motor.  Often a motor cable will break right at the terminal end at the motor or a motor terminal has become loose and burned.  A close visual inspection can reveal a lot.

Troubleshooting problems in these regen and sep-ex systems can be a long and involved process.  Indeed, the most modern controllers require a factory trained technician with special diagnostic tools to accurately troubleshoot failures.  When trouble does strike a service manual for the specific year model is strongly recommended along with a digital volt-ohm meter (DVOM).  If you are lucky and have access to known good parts then you can just switch stuff out till you fix it.  BEWARE:  These sophisticated electronic cars have a specific disconnect & reconnect procedure.  Be sure to carefully follow instructions so as not to create more trouble than you already have.  Your ability to repair any DC motor is fairly limited but I present a few concerns and procedures just below that include both the sep-ex design and the series design motors.

The last kind of electronic speed controller to cover is the one that started it all.  In 1990 E-Z-GO introduced the first mass distributed controller in the business, made by Curtis (PMC or Post Motor Controls, at the time).  Others soon followed.  This early controller simply regulated the speed of series wound DC motors.  Nothing fancy; no regen, just plain ‘simple’ speed control.  But gone were the broken resistors, the burned up speed boards, the complicated multi-solenoid/multi-microswitch speed & F&R systems and the ‘get the pedal to the metal’ driving technique.  Acceleration became smooth and continuous, with infinite speed control sustainable at any speed you needed.  These controllers did not shift forward to reverse, they did not slow the car in any way, as the regen controllers do–the series wound motor could not support these capabilities.  Problems here usually come from the controller itself, or from the pedal position sensor (called the potentiometer, or pot box, for short), from a solenoid going bad or because of a failure in either the small diode or small resistor attached to the solenoid terminals.   The pot box is directly connected to the acc pedal, it comes in various forms and it tells the controller at what speed to spin the motor.  The original pot boxes are mechanical switches that sends a pedal position signal to the controller, measured in ‘ohms’.

The series wound motor is a pretty durable part.  Outside of replacing a burned motor brush or the ball bearing, or a gross abuse of the motor, it gave very little trouble.  The modern motor brushes really don’t wear away like in older motors but the pigtail connector on the brush will sometimes burn out.  Sometimes the motor shaft spline adapter will strip out.  This splined adaptor is attached to the end of the motor armature and slips over the differential input shaft splines.   Under the right circumstances the splines finally wear out and although the motor works fine, it sounds terrible and the rear wheels will not move.  This requires replacing the adaptor and, sometimes, the differential input shaft.  While it is not as dire as it sounds, the repair requires some welding, a press and a snap ring pliers.  More to come!

STEP 4  –   Finalizing the Spring Prep:

a. Check the tire pressure and inflate to 20–25 psi.  If you have had any problems with a slow leaking tire, don’t waste your time with the foam ‘fix-a-flat’ stuff that comes in aerosol cans.  Usually it does not work permanently and can damage aluminum wheels.  I recommend taking the tire to a professional and having it plugged (it’s only about $5) or, if the tread is still pretty good, have a tube installed.  While you are down there filling the tires, look at the tread and sidewalls.  The tire tread wear should be even across the entire width of the tire.  If the center of the tread is worn too much the tire may be over inflated.  If the outer edges are worn away then a chronic air leak is indicated, maybe due to weather-cracked sidewalls or a pesky nail or golf tee.  (Sidewall cracks are very common and the cracks may or may not be the cause of the air leak.  Apply soapy water with a brush over the sides & tread of the tire and look for bubbles caused by escaping air.)  If one front tire is worn a lot more than the other, or the tread has signs of feathering or scrubbing in one direction, then a front-end inspection & alignment may be needed.  It is somewhat normal for a tire to lose 5 to 10 pounds of air pressure over a long storage.  Low tire pressure makes the battery pack have to work a lot harder to power the car around especially in grass or loose dirt & gravel.

b. In order to keep your steering system working smoothly and to prevent any metal-to-metal deterioration, it is recommended that your front end be greased at least once a year.  For those that use the car year round or use the car above and beyond ‘normal’ usage’, you may need to do this more often.  A simple grease gun with a flexible delivery hose is recommended for this step.  With the key ‘OFF’ and the F&R shifter in Neutral, jack up the front end.

CAUTION:  Always use jack stands or blocks of some kind when you are under the car.  Never trust a jack to hold fast and you can never be too safe.  The minute you let your guard down in situations under the car, bad things can happen.

On each tie rod end, steering gear box and kingpins, there is usually a grease ‘nipple’.  Wipe it clean with a rag and then press the end of the grease gun onto the nipple (also called a zerk fitting).  Be sure the end seats correctly.  Squeeze the trigger two or three times into each fitting.  Do not fill to the point where grease is running out everywhere.  If this happens clean the excess right away.  Grease is a magnet for dirt and if there is grease all over the tie rod ends, dirt will follow.  Older electric golf carts have grease fittings with only a few exceptions.  Don’t waste your time looking for grease fittings on most Yamaha cars, or on some of the most modern cars…there isn’t a single one.  They have a closed system which never needs grease (it actually works pretty well).

c. The beginning of the season is also a good time to be sure your brakes, brake cables and hill brake catch mechanism are all working.  It doesn’t do a lot of good to have a great running golf car that you can’t stop and keep stopped.  A hill brake lock mechanism that unexpectedly pops off is a mortal danger to anyone downhill from you.

Thoroughly inspect and test your brakes regularly.  Begin (with the key off and on flat ground) by pressing the brake pedal.  Feel to be sure the pedal doesn’t feel mushy or weak.  If the pedal tension does feel weak, you may have a frayed, kinked or broken brake cable, need to disassemble & clean the brake shoe adjuster mechanisms, or perform an adjustment to the turnbuckle or compensator spring assembly where the cables attach to the pedal underneath the floorboard.  Carefully check the cables for battery corrosion, rust, kinks or signs of fraying or unraveling.  You can purchase new cables.  If the pedal tension feels ok, but you still have to press extra hard on the pedal for adequate stopping, you may need to replace the shoes or inspect the brake drums.  You can purchase new brake shoes.  Any of these components or combinations thereof may need replacing or adjusting to achieve the proper brake feel.

With the vast array of shoes and cables out there, I have seen all kinds of jury-rigged combinations.  The correct shoes, installed & adjusted the proper way, with the correct brake cables & drums helps insure proper braking and personal safety. The hill brake catch mechanism is hard to inspect on any car. There are two parts; the notch (usually found on the hill brake pedal) and the catch plate (usually attached to the frame of the car).  Either or both can wear and unexpectedly pop off creating a dangerous rollaway situation.  The best way to check this is to get down with a flashlight and carefully look at both components for wear.  The other way is to lock the hill brake down as you normally would, then reach down with your hand and try to dislodge the catch mechanism by shaking & pulling at it.  It should hold very firmly.  If it seems to pop off too easily then there may be need of closer inspection.  Consult your service manual for complete instructions.

d. Check the differential gear oil.  This is often overlooked for years and lack of oil will cause the diff gears to start clashing, which leads to an audible gear whine noise as you accelerate, cruise or coast.  Lots of older electric golf carts have both a drain & a fill hole but on more modern cars the drain hole has gone away.  All of the modern Dana brand differentials take regular 30 weight motor oil but other brands may take heavier 90 weight gear oil.  It is always best to consult your service or owner’s manual.  If the oil is determined to be low; add to the bottom of the fill hole.  Be sure you are adding oil to the actual fill hole and that you are not overfilling because this can lead to other problems such as blown wheel seals and oily brakes.  I always look carefully for signs of oil leaks around the differential cover plate and at the end of the axle tubes where the wheels attach.  If things look oily or caked with damp looking dirt chances are you have a leak somewhere.

e. Check your reverse buzzer!  OK, OK, everybody hates these loud obnoxious intrusions while concentrating on backing up.  I find many cars that have a wire pulled or cut off.  Others that just don’t work.  I also find cars accidently left in the reverse position, standing quietly, ominously, waiting to unexpectedly go into reverse when the gas pedal is pushed.  Don’t do this!  That buzzer is for everyone’s safety.  With the modern ‘regen’ cars the buzzer functions as the ‘roll away protection’ warning signal as well.  In today’s market, where the majority of golf cars are used for personal transportation and where parking areas are crowded with other golf cars and people standing around, a disabled or broken reverse buzzer is inviting disaster.  And perhaps a lawsuit!  If the buzzer is too loud, locate where it is located on the car and partially cover the buzzer hole with a piece of duct tape.  This will cut down on the high pitch while still making enough noise to warn the driver, and those standing around, that the car is in reverse.  If you walk past an unattended car accidently left in reverse, do your neighbor a kind deed and shift it to Neutral.  The legs you save may be your own!

f. The last thing to really take a close look at is how tight the battery cable connections are throughout the electric golf cart.  I mentioned loose battery cables at the battery posts proper but anywhere the heavy cables are attached–the motor, the F&R switch, the wiper-style speed switch with the fixed copper contacts (older pre-electronic speed controller cars, 1990 & before), the newer electronic speed controller terminals and especially on the solenoid (the most common failure)–must have a clean tight connection.  Looseness=Heat.  Heat=Failure…sooner or later.  Again, if you can wriggle the cable end under the nut that secures it, it is loose!  If the entire contact moves on the board to which it is attached, then the contact is loose on the board.  If the cable end or the stud & nuts look oxidized, rusted or discolored compared to other nearby connections, it indicates a heat buildup and impending failure.  Deal with these problems while you have the vehicle where it can be repaired.  Otherwise you will be dragging that bad boy home. Good luck with all this and thanks for reading.  Call us at 800-328-1953 or 828-963-6775 (fax: 828-963-8321) if we can help you through any of these issues.  We carry lots of parts and service manuals.  Be sure to submit your email address (and any interested friends) so you all can receive our FREE twice-monthly newsletter featuring news, information, history and special discounts on parts & accessories.  You will find an email submission window on the top right of our homepage.

3 thoughts on “Put Spring In Your Electric Golf Cart

  1. Yesterday i installed new batteries in my 1992 melex 512 E and when i tried to attach the last #6 battery cable from the controller to the negative post it started arcing at the # 5 battery, i checked the battery cable installation sequence several times and it still arcs when i try to install the last cable to the negative post, the negative charge cable is already installed on the post with no arcing. Any ideas?

    • Honestly, I’d double and triple check your wiring. If everything is off, including key, lights, etc., there should be no arcing when reconnecting. At first glance that would almost seem like a dead short to me. In general for battery banks they are wired into “series” which would mean start at (+) on one battery, connect the negative of that battery to the positive on the next one, and so on, until you are left with the main (-) to connect last. My other question would be did anything “fail” in the cart prior to installing batteries? Did it run before changing batteries? The reason I ask that is sometimes people keep batteries too long. And as voltage falls, amperage rises. A significant increase in amperage could have over loaded any number of components, such as the solenoid or controller. Possible one of those is damaged and is permanently shut in the closed position, so basically you’re connecting a live circuit. Hard to say without looking at the cart. If you don’t have a good working diagram of the vehicle, please e-mail me personally at mike@golfcarcatalog.com. I’d be glad to e-mail you diagram for reference. Mike Williams, Product Development Director.

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