Visit The Dirt Forum for More Information

Author Topic:   Rear End Troubles
Vvv_JR_vvV
Dirt Newbie

Total posts: 4
posted August 10, 2003 10:23 PM  
Saturday night we had something happen that I have never seen before.

We are running a URC style (magnesium housing with an aluminum tube) quick change rear end on our 2001 Olsen. Eight out of the ten bolts that hold the rear cover on, backed out. These bolts were tightened and torqued. Of course, lost all the oil out of the rear. Good news is that it appears that it only burnt the spur gears.

Has anyone ever had any problem like this before? I am posting this in the modified tech and sprint tech due to the nature of this beast.

Thanks for any help,
JR

rocket36
Dirt Freak

Total posts: 209
posted August 11, 2003 03:23 AM  
never seen or heard of it happening before.
sounds nasty though.
probably a good thing you have still got the seals in the bearings (seperating the Q.C. housing from the crown wheel/pinion section) i have seen some people remove these to try and aid oil flow, but you would have lost the lot.
i'll have a stab in the dark of things to check, maybe something will help.

were the swivel washers (not sure what there called) that are on the end of the nuts in good condition ie. still rotate, and weren't crushed.

were the ball bearings still inside the nuts.

a question ??? did the nuts undo or were they forced off (stripped) this would take a heap of force but hey, anything is possible.

remember that they are only aluminium. that said, old age may have caught up with them too.

let us know if you find anything.

Vvv_JR_vvV
Dirt Newbie

Total posts: 4
posted August 11, 2003 03:29 PM  
The two that were left were still in good condition. The bolts were only 4 races old for fear of this problem. This is a Winters Quick Change Rear End, we have a call into them too.

Thanks,
JR

[This message has been edited by Vvv_JR_vvV (edited August 11, 2003).]

KSGerry
Dirt Freak

Total posts: 376
posted August 12, 2003 08:53 AM  
Originally posted by Vvv_JR_vvV:
The two that were left were still in good condition. The bolts were only 4 races old for fear of this problem. This is a Winters Quick Change Rear End, we have a call into them too.

Thanks,
JR

A a few thoughts here...Perhaps when the old studs were removed four races ago they damaged or stripped out the threads in the housing? Perhaps the wrong size or wrong threads for the replacement studs? Also if the threads on the cover side go past into the cover and the nuts are over tightened, this will pull the studs out of the housing.
Regards,
Gerry


------------------
KSGerry

Vvv_JR_vvV
Dirt Newbie

Total posts: 4
posted August 12, 2003 04:17 PM  
Gerry,

Out of these things you listed, the only possible thing could be overtightened. The new bolts came from Winter Motorsports, they were the correct ones. The threads look to be in great shape. It is not uncommon for us to change our gear twice a night due to everchanging track conditions. The housing still looks like it is new as do the threads.

Thanks for any help,
JR

KSGerry
Dirt Freak

Total posts: 376
posted August 12, 2003 09:11 PM  
JR,
Twice you mentioned that you have bolts holding on the rear cover. Do you actually use bolts or are they studs with nuts that secure the cover?

The reason I ask is magnesium and aluminum is very soft. The QC manufacturers know that the cover will be removed many times to change gears so studs are used not bolts. They are installed with a permanant-type thread lock compound and are a made from hardened steel...perhaps a grade 8. The nuts are made from a softer material. The soft nuts are supposed to prevent thread distortion and are meant to be regularly replaced. If the studs are changed, they may pull out the housing thread material. If bolts are used then the process of threading and unthreading will strip out the holes.

------------------
KSGerry

Back to the Archives