Cougar 2 diff problem?

[McMike]

Just been examining the rear wheel spin on my recently rebuilt Cougar 2 and think I may have spotted a problem. I have the team racing model so it has the slipper clutch on the spur gear if that helps anyone who may be able to help me.
Everything is hooked up and just waiting for my batteries to arrive and, for no reason, I decided to just spin the spur gear. It was then that I noticed the left rear wheel was spinning more than the right rear. The diff itself has nothing missing and was completely rebuilt so it operates very smoothly as a diff it just seems to have a problem now that it is inside the gearbox and is attached to the belt pulley. I don't know why the diff would spin the left rear quicker than the right in both forward and reverse.
Any ideas? Other than taking the diff apart again and rebuilding it I can't think why it would do this. I always had a problem with diffs anyway!
Cheers.

[BORMAC]

From memory the Cougar2 manual doesn't show any conical spring washers in with the thrust race. You may need to add some of these if you dont have them as the diff will heat up if the diff becomes too loose.

I experienced this problem myself years ago and it wasn't till looking at other model manual that Schumacher had slipped up here. My diff kept loosening off which inturn created more heat which transfered through the alloy diff carriers and melted the plastic outdrive. In the end the car wouldn't move at all as the diff had loosened to the point where the balls and plates were too loose.

[CAT3K]

Also check to see if you perhaps have a seized bearing on one side. Could be in the hub or the perhaps the diff outdrive bearing. That might cause there to be more drag on one side

[McMike]

Looks like I will have to take it apart then and rebuild it. I didn't use grease for the balls, just a squirt of motorbike chain lube. I know that isn't the 'correct' thing to do as it's a bit tacky but it also a great lubricant. It sure did sort out the awful grinding sound it was making when I got it so it's not a case of it being stiff on one side.
As I said, the diff is my weakness so I'm not sure about what extra washers to put in (if any) and where they might go. The diff is built to the manual.

[BORMAC]

I know this pic is huge but it best shows how I set my spring washers up on the adjustment screw. Without these there is no real way to adjust the diff tension as it's either done up tight or too loose. The foam ring is used to prevent debris getting into the thrust race. Works well enough for me.

[McMike]

Nice pic.
I took the entire thing apart and spotted the there was a washer or 2 missing so I stripped apart the spare gearbox I have from a Cougar 1 which has 2 of the conical washers as standard. The Cougar 2 just uses a washer over the mini ballbearing backed with another washer (this is the one that was missing).
So, in reference to you pic, I have 2 conical washers instead of 4 in front of the mini ballbearing assembly washer set up both facing towards the mini bearning. Seems to be running evenly now and I also tightened up the belt. If it still gives me problems, I will add another 2 conical washers as per you pic.
Cheers again!