overheating

[Jarrodnorris007]

I just recently purchased and installed a 36v 8.6 hp high speed d&d motor. I have 4 gauge wire and installed a 375 amp controller. It's a 2006-08 36v ezgo series model golf cart lifted, 14" wheels. I've also upgraded to a heavy duty f&r switch, and solenoid (solenoid maybe cheap ? Bought off ebay). Since I've installed everything I've had no problems (maybe a week, 2+ miles a day), except yesterday. I was riding around (maybe 1 mile) and it slowed way down. I pulled over and started checking everything out and everything was VERY hot. What could possibly be the problem? *thank you

your controller is not big enough ... need 500 amp
was it the warmest day after you installed motor?

[Jarrodnorris007]

Probably in the upper 80's

[yurtle]

Please be more specific on "everything's hot". Also, tell us the size tire, as that's where the rubber meets the road.

[Jarrodnorris007]

My motor, cables, f&r switch, controller, solenoid. Basically everything under the seat.

[yurtle]

Something is wrong if your 4 gauge cables are getting "hot" with only 375 amps. Solenoid gets hot under normal use, but we can't rule that out. The motor can safely get too hot to touch, but if you lick your finger and touch it, it shouldn't sizzle - kinda like our Moms did to see if the iron was hot enough.

What controller do you have? It may have gone into limp mode if it was overheating. Does it run normal after it's cooled down?

[Jarrodnorris007]

it's a ezgo controller. Yes after it cools down it runs fine, but after a mile or so it overheats again and slows down

[BobBoyce]

Originally Posted by Jarrodnorris007

it's a ezgo controller. Yes after it cools down it runs fine, but after a mile or so it overheats again and slows down

You did not answer the tire size question. Tire size is extremely important to the amount of power beng demanded by the motor. Larger tires slow the motor speed down. Motors are less efficient when forced to deliver a lot of torque at lower RPM. So going overboard on tire diameter will cause a motor to overwork while just trying to move a cart along. Excessive rolling resistance due to soft tires, soft ground, hills, ect will make this worst. This overheats the controller and everything in the loop responsible for supplying the current to the motor, and the motor itself. That stresses the batteries, solenoid, controller, motor, F/N/R switch, and high current wiring. The system is doing exactly as it was intended to do, slowing the motor down in an attempt to protect from overheat. Golf carts were engineered to drive on golf courses, at limited speeds, with stock sized tires/wheels. To take one outside of that operating envelope requires upgrading of all components affected, otherwise things will begin to fail. Sorry to be technical, but that's the engineer in me coming out. I've designed electric vehicles, so it is no suprise to me to see how golf carts respond when people make changes to tire size and how they are used, then wonder why these problems crop up. scottyb is probably one of the best ones here on this forum to help you find where the problems are, and what you will need to change to allow your cart to cope with the changes from stock, and how you intend to use it.

Bob

[Jarrodnorris007]

The tires are 23"

[BobBoyce]

Originally Posted by Jarrodnorris007

The tires are 23"

Ok, that is most likely the cause of your problem. Now, allow scottyb or others on here to tell you what you are going to need to buy and install to allow you to operate that cart with 23 inch tires, in the manner that you intend to use it. You might as well let them know how you intend to use the cart, the sort of terrain you intend to operate on, the pressure rating of the tires (determines tire drag), and any other load factors such as rear seats, cargo bed, ect. They can take these factors into account when calculating what upgrade equipment will be required. Welcome to BGW and good luck with your project.

Bob