No Torque!!

[Chad]

I have an 84 EZGO 36V. After converting it to a contoller I have no torque. I have checked and cleaned all connections, installed new batteries and tested each one under load ( none more than .5 from the others), checked the ohms on potentiometer ( my meter only reads to 2000 & had that at half throttle or less). Don't know what else to check! Anyone have any ideas? Matbe the controller? If so, how do I check it?

[Chad]

I forgot to add that the soleniod for the controller was bad so I put the soleniod on from the old resistor setup untilthe new solenoid comes in. Could this be the problem?

[Michael Eddie]

What were the results of the load test, first what are the levels of the batteries after full charge then what are the levels during the load test.

[Chad]

I have not charged the batteries yet. I am waiting to run them down a little first. I have the timer style charger not the auto and am afraid to over charge them. However the batteries brand new were reading 6.35 to 6.40, under the load they were reading from 6.23 to 6.16.

[Michael Eddie]

When you get new batteries you have to charge them as soon as installing them. A 6 volt battery should be reading a bit over 8 volts each on a full charge. The whole pack will be just under 50 volts. That is why there is a torque problem

[Michael Eddie]

Also....the stock solenoid you are running now is fine, you don't have to change it or replace it.

[Chad]

Thanks Matti. I will try this and let you know if that is what it was.

[Chad]

Matti I charged the batteries for 12hrs and they only got to 6.8v. Still no difference in the torque. It runs fine once you get going. Take is really slow forward and reverse. Do you think I can adjust the potentiometer? I also found another used Heavy duty solenoid that the guy said worked. Installed it and nothing. I have it wired according to the diagram you sent me. Install the one off the resistor setup and works fine. I drove the cart today about 2 miles and the solenoid and motor are hot. Hot enough where you can't keep your hand on them. Is this normal?

[Chad]

Matti I charged the batteries for 12hrs and they only got to 6.8v. Still no difference in the torque. It runs fine once you get going. Take is really slow forward and reverse. Do you think I can adjust the potentiometer? I also found another used Heavy duty solenoid that the guy said worked. Installed it and nothing. I have it wired according to the diagram you sent me. Install the one off the resistor setup and works fine. I drove the cart today about 2 miles and the solenoid and motor are hot. Hot enough where you can't keep your hand on them. Is this normal?

Need help please.

[Michael Eddie]

It is tough to say, but a hot solenoid most of the time happens when there is a problem with the motor, possibly a broken coil. You can get the same symptom if there is a dirty connection somewhere or if one is loose. Check the motor connections and for broken and loose wires, tug on them too. Double and triple check all connections.

[Michael Eddie]

You said you replaced the batteries right? What is the water level on them now? Also... How long did you use the batteries after installing them and not putting them on the charger?

[Chad]

It may be the motor. I will check it. It's weird because I had torque before the swap. The water level in the batteries is good and I did not run them far before charging. Maybe 1/2 mile if that.

[Chad]

Matti, I replaced all the microswitches and while doing so I left the battery cables unhooked over night. I hooked the cables up the next day and somehow I now have torgue. Enough torgue where the tires will now spin in the grass on take off if I punch it. I lost the torque one time while driving but it came back. I drove it for a little while up and down the ditch, never lost torque, but the motor is still getting very hot along with the solenoid. Do you still think it is a motor issue? If so do you have a diagram of this motor for a tear down and rebuild? It is an 84 36v direct drive (the motor is in front of the axle instead of on top). Model # on motor is 5BC48JB700A.

[Michael Eddie]

I was actually thinking it is more likely that you have a loose or dirty connection. Is the solenoid so hot you can get a burn from it? Also just some information...the batteries will need to break in for a few weeks and when that time is over you will be able to get the batteries up to full capacity, don't discharge them too much just yet.

I might have a diagram for you.

[Chad]

The solenoid and the motor were hot enough to burn you. I let it cool down for a while and drove it again and the solenoid felt normal but the motor was still a little hot, not as hot as before but still hot. What is the normal temp for the motor? Should it just be warm or is it normal to get a little hot? I was thinking new brushes in the motor or just clean them. Is this difficult to do?

[Michael Eddie]

The motor will get warm and hot sometimes depending on the terrain, that is fine. Brush check is pretty self explanatory and simple, blow in there with some compressed air while your there.

[Chad]

Seems like everything is good to go now. I don't know what fixed it maybe a bad conection in a wire because I recrimped all the wires (just replaeced #6 with #4) and evrything is good. Thanks for all the help Matti. I have learned alot through this little experience. I will let you know how the motor looks when I tear it down. Thanks again, the info is very much appreciated.

[Chad]

Ok Matti, The cart was doing fine until the other day. I lost the torque again. It sat for a little while and when I got back on it, it had torque again. I took it to the woods yesterday and it ran great for about an hour and it lost torque again with the motor getting super hot. I got home unloaded it from the trailer and it had torque again. I was thinking the brushes in the motor so I took it off to check. The motor was dirty so I blew everything clean. The brushes looked good and not worn down. The springs were good and holding pressure on the brushes. The only thing I am not sure about is that there was some play between the internal motor and I guess the magnets on the casing. You could wiggle it back and forth. If you hold it tight to one side it would have about 1/8" gap on the other side. Hooked everything back together and it ran great. let it sit for about 10 min. and no torque again!! Is it the motor going bad or is it something else like the controller/ F&R switch? I checked all connections again and everything is good.

[Michael Eddie]

Hi chad, How much torque is lost when it does it? Does it run okay on flat ground, can you climb a hill with it? Can you still go fast with it?

[Chad]

All torque is gone. It barely takes off in the grass (like you have to use your foot to get it going) and will not climb anykind of hill. If you stop on the edge of the concrete driveway (3" max) you can push the pedal to the floor and it will not move. On the flat asphalt it takes off really slow but once up to speed it seems to run ok. When it is running like this the motor gets hot enough to where you cannot keep your hand on it. The solenoid and controller are warm but not hot. I have a 4" lift on it but still running the stock rims and tires. It just puzzles me how it has torque sometimes and then it doesn't.

[Michael Eddie]

I am going to go with the controller on this one, this explains the cart being able to be held back. The hot motor does puzzle me and concerns me that there could be a wiring problem within it, so I am not going to rule out the motor either. The motor can be checked out at an electric motor/generator repair shop.

[Chad]

Thanks Matti, I will have the shop check the motor Monday and I will let you know the outcome.

[Chad]

Hey Matti, I had the motor checked. Everything tested ok. The motor was very clean and already had new brushes and brush holder installed. I am still having the same problem. When I lose the torque I can unhook the battery cables overnight and hook them back up and have torque again. Checked everything again ( batteries, connections, pot box, f&r switch). The only thing left is the controller. What do you think and is there a way I can check it?

[Michael Eddie]

Hey chad, where did you get the controller and is there a current warranty?

[Chad]

The controller is used. It came with the setup from the donor cart. Stock 90's model. Should I go with a rebuilt stock with 300 amps or go new? I am on a budget so I am leaning towards the rebuilt.

[Michael Eddie]

Rebuilt is fine, see what warranty you get with it.

[Chad]

Hey Matti, Sorry it took so long, but I just put the new controller in and everything seems to be working fine now. I have not ran it much yet. I will be taking it to the woods this weekend to give it the real test. Thanks for all the help. By the way I got a 2 year warranty on the rebuilt controller (300 amp) & only paid $250.Seemed like a good deal to me.

[Michael Eddie]

Glad to hear it, those problems are nothing compared to some of the $$ things $$ I have to go through on my carts