[transam1972]

boy, my boy..the last thing you need is no brakes after they launch you in that rocket your building...it will be interesting to hear some opinions on this..I would think it would have to get extremely hot to melt steel...you always got the emergency brake!

[jtwoods4]

Yeah.... opinions please

[transam1972]

NO SMOKING

[tabob]

I would re-route the brake line and fuel line WAY AWAY from that header if I were you.

[jtwoods4]

Well I worked out the drivers side brake line issue. Bent the line down about an inch and got about a 1/2 inch clearance from header. Then I double wrapped the line in 500 degree constant heat resistant wrap. The double wrap should really do the job. Today I finished the alignment and the Pro Touring F-Body Pro G-Brace install. They are tricky to install with 3.75 inch tall valve covers but I called Dave over at PTFB and he gave me some great suggestions that worked. Here is the video for today.

In the video I mention camber settings and I meant to say -.5 on drivers side.

http://www.youtube.com/watch?v=ye2cQ...ature=youtu.be

[jtwoods4]

New Maganflow Exhaust install. Kit 15899.

http://www.youtube.com/watch?v=QgHN2...ature=youtu.be

[jtwoods4]

Well after 2 days of driving, totaling about 50 miles. I started "feeling" a grinding in my clutch pedal. So I pulled in the driveway and dropped the transmission. The input shaft bearing retainer, you know the piece the throwout bearing rides on, was sheared right off! Then I looked down through the clutch and saw the pilot bearing also fell out.... what the hell.

My only thought of what could cause the bearing retainer to shear off after 50 miles is that the clutch linkage geometry was wrong and the bearing was pressing incredibly hard against the bearing retainer sleeve. When I assembled it everything felt great.

I have the stock original 1970 GM Clutch fork, z-bar (bell crank),pushrod, and pedal.
I have the QuickTime bell housing
TKO 600 transmission

Check out the video
http://www.youtube.com/watch?v=vOoaP...ature=youtu.be

[Formulabruce]

Originally Posted by jtwoods4

Well after 2 days of driving, totaling about 50 miles. I started "feeling" a grinding in my clutch pedal. So I pulled in the driveway and dropped the transmission. The input shaft bearing retainer, you know the piece the throwout bearing rides on, was sheared right off! Then I looked down through the clutch and saw the pilot bearing also fell out.... what the hell.

My only thought of what could cause the bearing retainer to shear off after 50 miles is that the clutch linkage geometry was wrong and the bearing was pressing incredibly hard against the bearing retainer sleeve. When I assembled it everything felt great.

I have the stock original 1970 GM Clutch fork, z-bar (bell crank),pushrod, and pedal.
I have the QuickTime bell housing
TKO 600 transmission

Check out the video
http://www.youtube.com/watch?v=vOoaP...ature=youtu.be

wow...TKO input sleeve isnt centered in the bell housing. Has to be a bell housing issue.. you run an adapter with the bell housing?
make sure the pilot bushing in the engine is in the middle, not too much grease behind it. ( offshore ones can be bad) There is some side torque on that sleeve in an elliptical shape going around. Ball stud on housing wrong angle, wrong place, or tranny mounts off ( bell housing) . Bad input sleeve? is that cast??

[jtwoods4]

No sleeve. Yeah I thought of a bell housing issue but that doesn't make sense. How would this cause the input shaft throw-out bearing sleeve to crack off. Explain the geometry of this. Especially after only 50 miles.

[Formulabruce]

Originally Posted by jtwoods4

No sleeve. Yeah I thought of a bell housing issue but that doesn't make sense. How would this cause the input shaft throw-out bearing sleeve to crack off. Explain the geometry of this. Especially after only 50 miles.

wrong throw out fork, ( for that bell housing) wrong placement of the ball stud it rocks on.., how did this feel before you started it, throw out bearing move smooth?

[jtwoods4]

Throw out fork is original 1970 Trans Am - GM Part. Seems like American Powertrain would have told me that I cannot use the stock fork with the QuickTime bell housing. Felt great when I assembled it. The pivot ball stud came already installed in the QuickTime bell housing. I did not change it.

[Formulabruce]

"wrong throw out fork, ( for that bell housing)" may be something to look into. Many parts these days are geared toward BBC engines and not Pontiacs.. I would also look at what that sleeve is made of, it looked cast. Hows the front trans bearing? did it allow the input shaft to move once the pilot was out?
The pilot really shouldnt have come out either , odd stuff going on..

[jtwoods4]

I am going to align the bell housing tomorrow. Engine builder said it was within .010 of center. I don't think Being .010 off center would break an input shaft bearing sleeve after 50 miles of driving.

[jtwoods4]

Originally Posted by Formulabruce

"wrong throw out fork, ( for that bell housing)" may be something to look into. Many parts these days are geared toward BBC engines and not Pontiacs.. I would also look at what that sleeve is made of, it looked cast. Hows the front trans bearing? did it allow the input shaft to move once the pilot was out?
The pilot really shouldnt have come out either , odd stuff going on..

Yeah this is weird and yes the bearing retainer is cast, ****ty Chinese part. I think it has to do with the clutch fork geometry pushing sideways into the shaft. Even though I did not notice an issue when test fitting. Since I cant identify the issue I am going to have to address everything. Align bell housing, call transmission folks and ask about original GM fork, etc.....

[jtwoods4]

Scroll down in the link below and read the paragraph right above the picture showing the throw-out bearing welded to input shaft. I only had 50 miles but I do see some metal build up on the input shaft where the inside of the throw-out bearing started to weld to the shaft, then the sleeve must have broken. Its got to be a bell housing alignment issue, which caused the pilot bearing to pry out, which caused the shaft to wobble in the throw-out bearing, then weld, then snap..... that makes sense.

Ahhhhhh, gotta love hot rodding

http://www.camaros.org/bellhousings.shtml

[Formulabruce]

that sleeve looks like cast, is it? ( at the break)

[jtwoods4]

Yes it is cast.

This comment I found on another forum from Jim over at Hurst Driveline sounds like exactly what happened

Broken front bearing retainers (throw out bearing sleeve) are usually the result of incorrect clutch linkage geometry. We have had a few of these break and the cause was incorrect geometry. A side force rather than a forward force being exerted on the throw out bearing can cause this. Lets wait until all the info is in before we come to any conclusions.

https://www.youtube.com/watch?v=vOoaPHKIQZM

[Formulabruce]

The spring retainers on the fork are not designed for that ball, and allows shifting of the fork possibly. Also the Ball stud can be higher than the factory one, or lower,changing the leverage too. I have seen forks slide though and wear that sleeve on stock units with aftermarket Forks. Looks like you have an Idea where to go... thats good..

[jtwoods4]

Originally Posted by Formulabruce

The spring retainers on the fork are not designed for that ball, and allows shifting of the fork possibly. Also the Ball stud can be higher than the factory one, or lower,changing the leverage too. I have seen forks slide though and wear that sleeve on stock units with aftermarket Forks. Looks like you have an Idea where to go... thats good..

On disassembly I checked the fork springs and they were securely mounted to the stud and the fork was still in the correct location. What fork do you recommend? What fork is designed for that stud?

[Formulabruce]

Originally Posted by jtwoods4

On disassembly I checked the fork springs and they were securely mounted to the stud and the fork was still in the correct location. What fork do you recommend? What fork is designed for that stud?

I dont know about that bell housing, was just tossing that idea out there that it didnt stay on the ball correctly. Still could be that stud height, or length of the fork from the ball to the Throw out bearing, the arc being too much and pushing sideways. I would find another fork and compare anyways. Bell housing stud placement can very much affect the arc the fork swings on.