Pulled the old clutch assembly off and the old pilot bearing is completely different from the bushing that came with the new kit. Different in every way, shape and size:
I'm thinking of just repacking the bearing. What say you all?
'68 428 HO M3 Monster, 4-on-the-floor! Need I say more?
Old bearing is a SKF roller bearing. New is a Bushing or needle bearing, I can't tell from the picture. I would only repack the old if you had to. It's a semi shielded roller bearing you can get one online if you feel it's better IMO it is.Try McMasterCarr.com Great place saved me many times.
No needles in that new bushing, Buckeye. Just a piece of alloy, smooth/flat on one side and contoured on the other.
I'll head to NAPA in the morning and see if they carry the pilot bearing. Also need a new brass or alloy "ring" that fits into the flywheel face, that the pilot bearing is tapped into. The current one has been "tapped" a few times too many. Looks like pilot bearing plus outer ring equals 1.75 inches in diameter.
'68 428 HO M3 Monster, 4-on-the-floor! Need I say more?
an SKF bearing should easily re pack...best steel in the world! SKF Svenska Kullager Fabriken =Swedish Ball bearing Factory.....the 'mother' of Volvo...Volvo was derived out of that factory in 1927
Uh oh sports fans, it appears I have a dilemma. The new flywheel center area for the pilot bearing is 1.75 inches across, much larger than the bearings or bushing that I have used in the past.
Anyone know what FGF flywheel has a 1.75 inch diameter bearing/bushing? I either find that larger bearing/bushing, or use the old flywheel again.......
'68 428 HO M3 Monster, 4-on-the-floor! Need I say more?
First off the bearing doesn't mount into the flywheel, it goes into the back of the crankshaft. Should be no big deal reusing the old bearing. They don't usually wear out. If it did I would take it down to the parts store and tell them I wanted one just like it. Don't use the bushing. It will work but it's not what you want in there.
Have you looked at the new throwout yet? There are at least two different lengths of bearings. Some kits come with a different length and when you try to put it in you only end up with partial clutch throw.
Yes to all, I am re-learning this whole fiasco over again. Having bigtime deja-vu as we try to force the "parts system" to match up to what we need for this application.
Of course the bearing does not set in the flywheel itself, but once the flywheel is installed it all looks like one face, crankshaft and flywheel together.
'68 428 HO M3 Monster, 4-on-the-floor! Need I say more?
Put everything back together but something is not right. Pedal must be pushed to the floor to engage clutch; Drives fine when in gear, but noise and vibration while shifting gears (when clutch pedal is pushed going into 2nd, 3rd and 4th gear). Didn't have a chance yet to do any linkage adjustment.
'68 428 HO M3 Monster, 4-on-the-floor! Need I say more?
Sounds like the clutch isn't disengaging all the way. I'd bet wrong throw out bearing but I know you checked it against the old one before installation. Did the clutch disc have a mark on it saying this side out? I know it sounds crazy but I've tried to put them in backwards before.
The new T/O bearing came with the new kit, and it was of the "smooth face" type. I am used to the other "rounded face" type T/O bearing, but figured NAPA knew how to build and match up a clutch kit!
Adjustment rod made nothing better today.
'68 428 HO M3 Monster, 4-on-the-floor! Need I say more?
I trusted "the local NAPA guy".....even though he is missing 9 or 10 teeth, I trusted him......he swore their clutch kit was matched and right for the application.....even gave me a military discount.......
'68 428 HO M3 Monster, 4-on-the-floor! Need I say more?
I changed my clutch last year and had trouble with the throw out bearing. The old clutch was the three finger type and the new had the vanes. I put in the new clutch and had the same problem as you are having, I took it out and put in the old throwout bearing and it worked fine. You may be able to adjust the throw out lever ball stud in the bell housing, I've heard some are adjustable.
The parts store guy is probably just reading what it says in his catalogue from the manufacturer and they seem to be wrong as much as right. The flywheel they had listed for my 428 had a register for a small flange crank and mine is a large flange and the clutch disc was an 11 inch and would not fit inside the bolt hole pattern for the 10.4 inch clutch, yet all were listed for the 428 and the 428 equipped cars in the parts book. After going by boat to SS island three times to return parts I tried the napa in Sidney and they got me a clutch after I took the center-force number into them. They couldn't seem to find me a flywheel although the store down the road could get me four different brands. I had the flywheel resurfaced, through away the throwout bearing and the chevy pilot bushings that cam with the clutch, and everything works well now. It cost more when you have to replace new parts, but at least I have a 428 not a 396 or 427.
Info I've read but cannot confirm: Pilot bearing #7109- GM part #15533265 slip fit with the cover facing out stake to retain; Pilot bearing #6202 may be used but pilot bearing hole might not be deep enough.
The pilot bearing I got with my Tremec tranny kit was a National #7109
OEM/original bell housing ball stud that holds the clutch fork are not adjustable. Hurst makes one that is adjustable. However, I tried that and what it does is ultimately mask the real problem and throws the geometry off etc.
Your problem likely stems from having the wrong throw out bearing. If you are using the short one, then this would explain why you are not dissengaging fully...
The crank register is the part that extends out from the crank flange that the hole in the middle of the flywheel fits over, it centers the flywheel onto the crank some were 2-3/4 inch dia. some were smaller. The catalogue the napa guy used stated the flywheels would fit all years and sizes of engines which just isn't so, and he wouldn't know any different.
The hole drilled into the end of the crank is what the pilot bearing fits into. As far as I know the pilot bearing holes were all the same size to fit the 1.387 inch outside diameter pilot bearing which is close to 1-3/8 inch. Some of the later automatic tranny engines did not have the pilot bearing hole drilled. You stated earlier you needed a new brass ring that the bearing was pressed into maybe someone drilled the pilot hole oversize then put in a bushing to reduce the size of the hole to fit the bearing. Just guessing here.
The crank register is the part that extends out from the crank flange that the hole in the middle of the flywheel fits over, it centers the flywheel onto the crank some were 2-3/4 inch dia. some were smaller. The catalogue the napa guy used stated the flywheels would fit all years and sizes of engines which just isn't so, and he wouldn't know any different.
The hole drilled into the end of the crank is what the pilot bearing fits into. As far as I know the pilot bearing holes were all the same size to fit the 1.387 inch outside diameter pilot bearing which is close to 1-3/8 inch. Some of the later automatic tranny engines did not have the pilot bearing hole drilled. You stated earlier you needed a new brass ring that the bearing was pressed into maybe someone drilled the pilot hole oversize then put in a bushing to reduce the size of the hole to fit the bearing. Just guessing here.
As Earlybird stated, if the throwout bearing is too short it will not release the clutch. the only way I got mine to work was to replace the short throwout bearing with the original length one.
This is a good lesson for anyone replacing a clutch in their Pontiac. Always compare the throw out bearings (old with new) when replacing. If the old was working, be sure to replace it with one that is the exact same height. Simply set them on a flat surface face down and compare them...
Good advise, and not to complicate things- if the pilot bearing is not inserted correctly or somehow binding on the tranny input shaft it could cause the input shaft to turn when the clutch is disengaged. A misaligned bellhousing to crankshaft could also cause the same problem. If the centerline of the crank is not aligned with the centerline of the bellhousing, or of the bellhousing to block mating surface is not perpendicular to the crank it could cause clutch disengagement and shifting problems.
Nashville, are you sure the bellhousing is seated correctly against the block and not binding on the dowel pins? Just a thought.
IMO throwout bearing is incorrect. (.) Inproperly installed pilot bearing will be know ASAP. Incorrect bellhousing alingment will cause premature clutch failure due to side load on the splines and can even cause the input shaft bearing of the tranny to fail. Bellhousing can be checked and fixed with offset Dowels.Had this happen 30 years ago and caused me fits...no help no internet and a crappy old chiltons. Took it all back apart at 2 in the morning with help from Bud Wiser and matched up all the part old and new and found the problem. Quit trusting the Auto parts guys there and then. (.)
I jacked her up tonight and pulled it all apart again. I think you all are right on the T/O bearing, as I've always used a larger rounded face bearing, like Bobs photo above, but the kit came with the smooth-faced one and I assumed ( )it was a matched set. SOB!
Might get it all back together after work tomorrow PM and let you all know how it goes.
'68 428 HO M3 Monster, 4-on-the-floor! Need I say more?
I ended up using the short flat bearing with my new clutch set up, though it had the longer bearing with my previous clutch. It seems to work. Maybe I got lucky or else it's going to bite me eventually. I ended up getting a different push rod assembly which let me adjust it correctly. The geometry of the throwout lever may be wrong, though.
I tried the longer push rod but it wasn't quite enough. I thought I could use the shorter throw out bearing as I changed from a three finger clutch to a vane type. I should have done as Earlybird suggested and compare the two on a bench and put in one of the proper length from the start.
I already made a longer rod a few years ago, so no room left for that trick, thanks to the headers.
Check it out....the new one I got from O'reillys today on the left, and the new flat-faced one that came with the "matched set" clutch kit from NAPA......like night and day....WOW look at the difference in height.
I installed the bigger one in tonight and man she is shifting clean and smooth!!! Need to tighten the linkage up a bit but it appears all is well.
'68 428 HO M3 Monster, 4-on-the-floor! Need I say more?
Nice job glad it's back up remember to check the bushings in the linkage and replace any that look dryed out. A cracked bushing that shifts and breaks under load on a hard shift...not good.
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