Tranny clutch cable wheel failure

John Rogers · 11-14-2002, 11:02 AM

Has anyone experienced the wheel that the clutch cable uses for changing direction deforming and letting the cable come off? I have had this happen twice in the last couple of months although the wheels were probably old (age?) One failure was in a practice race at Willow Springs and the other was exiting a freeway in San Diego , both just as I do a downshift. I thought they were pretty strong. I do use a 3500# pressure plate in the race car so there is a fair amount of pedal pressure over stock. I am debating buying one of Jim Patrick's delrin hard ones? Any ideas?

tbil · 11-14-2002, 11:10 AM

Haven't had that problem - wouldn't have guessed it possible but with age....

I have had trouble with binding and finally noticed that the wheel on my 75 is not the same on both sides. As I recall there was a little difference in offset and when put in what I think is the wrong way, brings the cable too far near the metal cover. Wouldn't guess that this would cause your problem though.

Good Luck!

seventythree · 11-14-2002, 03:08 PM

I vaguely remember a thread on the subject of the clutch cable acting as an electrical grounding path, overheating, and resulting in a cable related failure. Look it up, it may just be the answer to your problem.

kellzey · 06:12 PM

John:

I'm interested in the delrin plastic replacement wheel you mentioned that Patrick Motorsports carries. I can't find it on their site. Do you have a link or know how much it costs?

I'm getting ready to install a high power, high torque motor in my car with a beefed up 901 and a 9" Stage II pressure plate and clutch package from Kennedy Engineering Performance. I'm worring about that plastic wheel failing.

I'd like to find a better solution in a harder plastic or in metal.

Anyone else have any input?

Thanks,

Zeke · 11-14-2002, 06:02 PM

I thought someone made one out of aluminum. If it hasn't been done yet, why not? While they're at it, how about a bearing in the center? Brad?

red-beard · red-beard's Garage

John,

If you need one, I probably have one or 2 laying around the garage. I'll trade you for "Tijuana" lanuage assistance from your wife...

James

URY914 · URY914's Garage

I had my cable digging into the wheel. You could see the cable strands embossed into plastic wheel. I think heat and age gets to the plastic.

Brad Roberts · 11-14-2002, 07:49 PM

We sell billet aluminum wheels. Forget the plastic ones all together. We have had to gusset the pivot bracket also (V8 914's)

I think the roller bearing idea is pretty damn good. Havent really thought about it. It definately wouldnt hurt. It might even smooth out clutch engagement. Humm..

Normally JohnR, its the heat from the header causing them to fail.

Is your race header ceramic coated ??

B

John Rogers · 11-15-2002, 05:34 AM

Thanks for the input. I did check the trans ground and it is good and no resistance between the tranny and body as measured. Patrick's phone number is on their site, I'll see them next weekend at the HSR race in Phoenix and get one. They use the fiber reenforced delrin which is good to over 500 degrees. The headers are coated and wrapped but it gets pretty hot under there anyways? Last night I made a cover that uses the center nut to hold it on and wraps around the outside of the support bracket so this should add some reenforcement. Thanks again for the ideas.

kellzey · 11-16-2002, 07:28 AM

Where would one go about finding a bearing to fit this application?

I'd like to see a bearing fitted to one of the aluminum wheels Brad mentioned?

Where would you want your tolerence fit to be? On the wheel, on the wheel shaft, both?

I think the bearing idea would be neat. Probably overkill, but it would be a "neat" addition, and iti could smooth out the clutch action a little.

Brad... you wanna provide some more ideas?

Regards,

John Rogers · 11-16-2002, 07:49 AM

I have a lathe and considered making an aluminum wheel but I am concerned about the steel cable on the aluminum and what might happen. I imagine the wheel is supposed to turn, but I'm not sure I agree that it does? I'll try the delrin then see if the aluminum is needed? Bearing can generally be found at a commercial bearing distributor and I think a sealed roller bearing could be measured and found?