RC10Talk - The Net's Largest Vintage R/C Community

Eau Rouge wrote: You should not be able to turn the center gear by hand when holding the outdrives stationary. Keep tightening the diff slightly until you just can't move the center gear.

Used some piano wire bent into a U. This technique worked well, much less ambiguous than the AE manual method!

This time around, using a loop, I noticed that the diff balls had little patches on them where the chrome wore off. I guess I just missed it last time... Since I've got new drive rings and thrust bearings/washers, I'm gonna conclude it's the diff bearings. Maybe 18 years is a bit much to expect out of a good chrome job? Next time I swing by the LHS, hopefully I can put this to an end!

Thanks!

Wait, you really used the old diff balls-

Well, the manual swore they'd outlast the drive rings 10X over... In my defense I've never actually claimed to be smart in this conversation....

Do not waste money on diff balls just yet!

[youtube]0SDrqa-eTXU[/youtube]

RC10resto wrote:

Do not waste money on diff balls just yet!

[youtube]0SDrqa-eTXU[/youtube]

Just another reason to invade Canada

You rarely have to replace the "carbide" original Stealth diff balls! You know this guys! And they do not cost one dollar to replace! More like $1.00 each X12! http://www.teamassociated.com/parts/details/6581/

slotcarrod wrote:You rarely have to replace the "carbide" original Stealth diff balls! You know this guys! And they do not cost one dollar to replace! More like $1.00 each X12! http://www.teamassociated.com/parts/details/6581/

This is very true! I did spot some carbides of the same size and count on Tower from uhh... Acer I think? They were only 8 bucks for twelve... Maybe I'll just live with it until my next Tower order...

You know this guys!

But then I would not have been able to post my South Park link - c'mon Rod

slotcarrod wrote:You rarely have to replace the "carbide" original Stealth diff balls! You know this guys! And they do not cost one dollar to replace! More like $1.00 each X12! http://www.teamassociated.com/parts/details/6581/

I use IRS standard ones, never used the carbide ones

alright let me chip in

el-cheapo steel balls are perfect if you don't mind regular maintenance

carbide tungsten balls are probably the best for the "average" basher as they're still affordable (pick another brand than AE's 3/32, they are way overpriced and not that much better than others') and last much longer than steel

ceramic balls are great for smoothness but they are so hard they (i) wear out the rings pretty fast and (ii) reveal any diff "imperfection" in alignement and other sources of grittiness and (iii) the slipping/locking tuning window is harder to locate.

and I completely agree with Doug that you should tighten - check - tighten - check and so on rather than tighten all the way thu and back out which does at least two bad things (i) can flatten balls and mark rings and (ii) puts too much tension in the diff screw and raises the risk of it snapping later on

My 2 cents

paul

Well, I'm pleased to say the grit is officially gone for now! I picked up some Losi steel balls for 2 bucks at the LHS, and installed them using Eau Rouge's technique. My diff may not be exactly butter-smooth, but at least as smooth as margarine, or maybe I Can't Believe It's Not Butter! I think it's probably better adjusted than it ever was back when I ran this car in the 90s, and I thank you for that, Rouge.

Hopefully this is the last time I open up the diff for a few months at least! Thanks to everyone who offered advice, this forum rocks!

Another thing is that with some diffs you just can't seem to build them right. They'll never be really smooth, always feeling a bit gritty, even if you used new diff rings/balls/thrust bearing sets.

Until you actually run the car, and the diff sets a bit.

If you want it even smoother, try replacing all your bearings with new ones. I use to rebuild my pan cars with new rings and diff balls and wondered why it still felt gritty. I realized it was the ball bearings and replaced those. Smoooooth!

In the last 15 years I can count on one hand with extra fingers how many times i have gotten a smooth diff even with new parts. However this last time things went alot better. I went with ceramic balls all the way through, new rings for the main and thrust. The main difference is I left it mostly loose when I assembled it. I then put it back in the transmission case and asembled the car with the exception of the right hub and axle. I then ran it up to 1/4 throttle with the left tire held solid. From there I slowly tightened the thrust screw as it spun and let it seat in as I went. This is the first time I can remember in a long time there is no grit at all in the diff and its smooth. I also put a used shock o-ring in the right outdrive and pushed it down around the thrust screw head to act as a seal to try to keep dust away from the thrust bearings. So far so good. I will find out next month how well it lasts under race conditions.

Nick

cautrell05 wrote:In the last 15 years I can count on one hand with extra fingers how many times i have gotten a smooth diff even with new parts. However this last time things went alot better. I went with ceramic balls all the way through, new rings for the main and thrust. The main difference is I left it mostly loose when I assembled it. I then put it back in the transmission case and asembled the car with the exception of the right hub and axle. I then ran it up to 1/4 throttle with the left tire held solid. From there I slowly tightened the thrust screw as it spun and let it seat in as I went. This is the first time I can remember in a long time there is no grit at all in the diff and its smooth. I also put a used shock o-ring in the right outdrive and pushed it down around the thrust screw head to act as a seal to try to keep dust away from the thrust bearings. So far so good. I will find out next month how well it lasts under race conditions.

Nick

Interesting!