XingXing

hi. is there a problem with the pin in the rear ball diff? they break easy?

EricO3

Are you referring to the Diff Screw that goes through the middle to hold the two halves together?

XingXing

yeah the screw/pin that you adjust to set the tightness of the ball diff

RC_Woody

The original ones had a tendancy to stretch and break. If it breaks inside the diff half you basically have to replace the whole diff half.

the new Diff screws which have a solid lip with no threads around the head are much stronger and work well.

If in a pinch and you have the old one use it, but I would replace it ASAP.

Woody

duckman996

iTrader: (14)

I will try that ... I really hope that it is the solution to my problem. Thanks for the advice guys.

duckman996

iTrader: (14)

You can actually get the broken screw out without damaging the hub ... what I have found is that if there is enough of the screw visible, take a small file and file a slot into the screw - then use a small slot screwdriver to unscrew the broken part from the hub. Now if Corally would sell the plastic insert seperately, you can actually drill out the old plastic unit (carefully) and replace it with a new one ... Corally - any chance that the insert can become available seperately???

CrashTstDummy

Duckman.check where you buy your Corally parts from and they may have the small insert to give you as a replacement at no cost

RC_Woody

I'm not sure what you mean my drill out the old plastic unit, but if you look at a undamage diff half, there is actually threads in the metal part of the diff half that the diff screw threads into right before it reached the plastic insert.
Also if you do happen to salvage a diff half that you think will still work, Call CorallyUSA and they will send you some of those black plastic pieces.

Woody

EricO3

The plastic insert comes out easily if you heat it up with a hair-dryer/heat-gun. No need to drill it out really.

Jeff Brown

Hopefully we will offer the snap rings and diff nuts seperately. The Snap rings are easy. The diff nuts we currently provide for a quick fix for people at no charge. The new diff bolts seem to be working out nicely. If you see your diff loosen from one run to the next and you tighten it a couples, STOP. The bolt is probably stretching. So save some hassle and swap it out.

One thing we recommend is to use loctite on the screw even though it is going into plastic. The diffs seem to hold up better all around if you apply a dab.

Jeff

or8ital

iTrader: (38)

So has this been a problem? I have the EXACT same problem. My car shakes violently when I turn the wheels to a certain point. Definately seems to be some kind of frequency thing b/c the point it happens changes based on speed. At lower speeds I have to set my EPA down to around 30% to get it to not do it. I cant image I will be able to get much of a turn at 30%. The shaking seems awfully violent for there not to be something wrong. Its definately not hitting on anything. Perhaps its a problem in my diffs? They are a bit wobbly but I have rebuilt them a couple of times to try to eliminate it and just cant do it.

duckman996

iTrader: (14)

I just ordered a couple of the new diff bolts ... and a couple rebuild kits. I hope that the snap ring has been my problem.

duckman996

iTrader: (14)

Sorry - to be more clear, one you remove the broken screw and if you find that the plastic nut as found in the drive cup is damaged (stripped, etc), you can drill it out from the outdrive side and replace it with another nylon nut ...

I made this recomendation before I knew that you could remove the plastic with a little heat and Corally has the replacements.

Korey Harbke

iTrader: (13)

The diff pulleys should wobble a tiny bit. The Diff probably wouln't work properly otherwise. Do you only notice the shaking when the car is driving or when the tires are lifted off the ground? They will do that when there isnt any weight on the tires... All cars will do that to a certain extent.

I have a problem when I was using the CVD bones for the steel blades. The pin shifted slightly and moved so it was hitting the bearing that retains the diff. This caused the car to do all sorts of funky things, but you wont have this problem with the standard bones.

How big of a circle can your car turn around at low speeds?

-Korey

tbeardmore

iTrader: (3)

I think I know what your "shaking" problem is.

I think it's the outer CVD "Cross pin" that drives the FRONT outer axles. The "set" screw may not be tight. If the set screw isn't tightened properly the drive pin will shift - hence rubbing on the INSIDE of your steering blocks.

If you have the aluminum steering blocks - it'll be easy to see if there's been some "pin rubbing" on the inside. If you are using the black plastic steering blocks the pin "wear" markes may not be as easy to see.

I've actually had a pin loose like that and it worked it's way into the holes where the C-Hub pins are and completely lock up the axle/wheel.

An easy fix for this is to "dremel" a flat spot in the center of the "cross pin" so when you re-tighten the set screw that holds it in place - the set screw will have a liitle more grip to hold onto. (ps. put a small amout of threadlock on the tip of the set screw- that'll help also)

Hope this fixes your ~SHAKE~ ??