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I have a 1990 championship edition and I stripped my 32p spur gear. I installed a 48p spur and stripped that too!

I meshed the pinion and spur correctly and installed new carbide balls in the spur gear.

I noticed there was a wobble from side to side on the spur gear, and I thought the diff balls worn down, causing the side to side play on the spur gear. Installing new carbide ball diffs didn't help.

Any ideas why the spur can still move side to side?

Diffs do that. That's normal. It should self center when the pinion is turning it. What are you using for a motor?

Was the motor still tight when you found the gear stripped?

Make sure the diff rings are fully seated as well. Sometimes they can pop out of alignment during assembly.

- Limestang

If you are still stuck, post some photo's. That usually helps.

- Limestang

Sounds like you have an old 6 gear transmission CE... if what you're describing is shaft play, I'm willing to bet you have worn or missing teflon bushings #6623. If it's not that, maybe you have a bent motor plate? Hope you sort it out!

I replaced the Teflon bushings , top shaft, spring and nut, diff rings, carbide balls and still spur play side to side AND forward backward. When I properly mesh the spur and pinion, give it throttle, the mesh is off. . Not sure why all this slop. Maybe the associated spurs I've been using have a hole slightly bigger than the shaft causing the side to side and forward backward play

VIDEO:
http://www.youtube.com/watch?v=P4ljGbgsVWI

any spur is going to do that on a 6 gear, though some may be slightly better than others. it's just the way it is. just make sure the spur is running true when you set the mesh. that's about all you can do.

try a kimbrough spur.

Gtstwincam wrote:When I properly mesh the spur and pinion, give it throttle, the mesh is off.

This alone leads my to believe your motor is moving.

Do the mounting holes in your motor have a bottom or could you turn a screw all the way in and bind up the internals?

I'm guessing yours have a bottom so that doesn't happen and when you think you're tightening your motor all the way, you're actually just bottoming out the screws and not getting the motor tight enough to the motor plate.

Strictly a guess since you're stumped and we're just throwing out ideas.

If this is possible, try shorter screws.

Or if it's lateral movement, which after reading again it sounds like it might be, maybe your diff tube isn't pushed onto the shaft far enough....or too far?

A bit of lateral movement is normal. The spur itself can wiggle on the balls and the shaft can move through the transmission a few mm.

Update:

It's lateral movement strictly within the spur, carbide balls and the two plates.

I was up late last night, tinkering with it and there is a BIG improvement from the rebuild and replacing the bushings with bearings. The Teflon bushings has eliminated the forward/ backward /up/down shaft play!

It appears that this lateral movement is normal. The only way it looks to be corrected is if the spur was thicker, reducing the lateral play.

I test drove it at 3am last night (lol) and it ran ok with the leopard 3300kv brushless motor with punch control and timing set to the lowest settings to go easy on the spur and tranny.

Btw, I noticed the chassis is double stamped with TWO A's (AA). Is this an error chassis or was this common on a 1990 championship edition.

Glad to hear have it fixed now. I had the same problem a couple years back, it was quite frustrating to say the least.

Oh by the way, I'm interested in seeing your "GTS twin cam" since it sounds like a celica

teman wrote:Glad to hear have it fixed now. I had the same problem a couple years back, it was quite frustrating to say the least.

Oh by the way, I'm interested in seeing your "GTS twin cam" since it sounds like a celica

Its actually an AE86 Toyota corolla GT-S . Sold it years ago and drive an s14 240sx

From what I've read the double A stamp is a fairly rare production error. It adds to the collectability of the chassis.

- Limestang