pool1027

Hi guys I need some help. I have a TC4 electric car and when I was driving it the other day it started to slow down and then come to stop. At first I thought it was the batteries so I changed them for a fully charged pack it moved off ok but then did the same thing again. It seems that when it is on the ground it does not want to move and the motor is moving but the car does not seem to be getting any drive. When I take it up off the ground the wheels are moving fine. I would appreciate any help on this. I am also thinking it might be diff gone bad but not sure how to check if it is the diff.

Hyde

iTrader: (1)

How old are your battery packs? If the wheels move fast, when the car is off the ground, but the car moves slow when the car is on the ground, than its your batteries

Does the motor spin fast, when your car is on the ground?

mpboost

If the motor/battery/electronics check out fine, you can also try putting the car down with all four wheels touching the groung and try turning the spur gear by hand to see if there are any issues with the drivetrain.

If you are able to spin the spur gear without the car trying to move or if the spur gear can slip, there are a couple things I would check:
1) Make sure your spur gear still has all three screws holding it to the hub
2) Pull your input drive cups off the front and rear transmisson cases and make sure the pin/pin groove are still intact.
3) Make sure your differentials are not loose and slipping.

pool1027

Mr Hyde the wheels move fast when the car is off the ground but when it is on the ground it sounds like the motor is spinning fast but the car moving slow.

pool1027

mpboost i will check and get back to you

pejota

iTrader: (12)

Check your differentials, front and/or rear. Sounds like they are slipping. In other words, the screw that keeps tension on the assembly is loose and needs to be tightened. The gear is spinning but there is no tension to make the outdrives turn.

If all of that doesn't make sense, look in your manual and read the instructions on building your ball diffs. If you don't have a manual-- www.rc10.com-- go to the support section and download the manual in PDF.

pool1027

pejota I will check them now

pool1027

Ok guys I just came back from testing the car. I checked the car by putting it on the ground and moving the spur gear and the car tried to move as I moved the gear, I also checked to see if the screws were tight on the gear and all three were tight. Now when I drove the car it moved off a little sluggish as I was driving it around it began to slow and then come to a halt. Th motor the drive shaft would spin at a fast rate with the car not going anywhere. Then if I let go of the throttle and then go back on it the car would move but very slowly. What do you guys suggest I do from here do I pull down the diffs or do I check something else first. The electrics seem fine and the motor is spinning ok could it be the speed control. Let me know your suggestions.

robsdak

this can be done in car. no need to take it apart. go to pdfgeni.com/book/outdrive-pdf.html and find #3913 Molded Outdrive Assembly... this explains it.

pool1027

How would I check this in car. I would have to take off the shock towers and transmission case to get to the diff

robsdak

take the linkage off of the transmission braces and swing the A-Arms and dogbone out of the way and stick 5/32" allen wrench and see if you have the right side. if not, you have to do the other side.

just tighten up your diff's. it's a simple fix. google AE TC3 or TC4 manual, it will be in PDF format. download it and see what i am talking about...

of you follow the link i sent in your PM it shows how the diff. is built...

pool1027

robsdak I see what mean I did try and I tightened up the diff a bit. I will try the car and let you know if it worked

pool1027

Ok guys I tightened the diffs and still have the problem of the car driving and coming to a halt with the motor, drive shaft and spur gear just spinning. I checked in the transmission and the gear look fine so I am at a loss to what is the problem.

DaveW

iTrader: (1)

Sounds like a drive pin in the main layshaft may be missing or broken... although that is very uncommon. You need to pull the main layshaft (the one with the spur) apart and compare it to the blow up diagram of the Tc4 to be sure all parts are there doing their job...

pool1027

ok I think I have found the problem. I decided to pull down the rear diff and found that plastic out drives are worn down to the drive rings so I assuming that will cause the slippage. I presently looking for upgrades in the diff area for both front and back. Any suggestion would be appreciated.