Car is 88 Supra with 1JZ and R154.
Background -
I've got an ACT HD Pressure Plate and an HPF Bronze 6-puck unsprung clutch disk that I am replacing my stock clutch/PP with. I had the flywheel machined by one of the best shops in FL with the correct step, they took care of the flywheel dowels. I followed the TSRM, threads from this forum, and common sense carefully and completely with the exception of over-torquing some bolts past TSRM specs.
I got all OEM Toyota parts and replaced the flywheel bolts, pilot bearing, rear main seal, and throwout bearing. I replaced the Redline fluid with Torco SGO.
Problem -
Car has a drivetrain vibration/unbalance from first startup after install. Doesn't stop with RPM change or clutch release engagement. It's hard to explain, but the engine has a quick repeating up and down, like what you would expect with a pressure plate out of balance. Visually, I can't really see anything obviously out of alignment when the assembly is turning or stopped, but it probably doesn't take much to create the vibration/balance issue I'm getting. I took the clutch fork out and took the PP off the flywheel again, everything looks great.
Question: Does the PP usually slide onto the flywheel dowels easily? I cannot get the pressure plate to interface with all three dowels without persuasion, like working the 2nd or 3rd dowel with tapping on the PP and tightening the pressure plate bolts strategically to get the dowels in the PP.
The first time I installed the PP, I just assumed this was normal to hold the clutch tightly in place. Now after the problem I'm not sure. I'm not sure if it matters because the bolts all go in fine.
Possible Solutions-
These are the things I think could be causing the problem.
- Pressure plate bolt length and machined flywheel. After thinking about it for a bit, my first thought was maybe the bolts for the pressure were too long now that the flywheel has been machined. They could be bottoming out and creating the illusion the PP is tight, but it isn't. I tested the bolts with a sharpie mark and they are damn close to being too long, but they tested OK by a slim margin. Still possible maybe? The PP looks tight against the flywheel.
- Unbalanced pressure plate from ACT. Does this ever really happen?
- Something funky on the first PP install. I guess this is the "I dunno, but I hope it magically works this time after not changing anything" solution. Maybe something didn't sit right with my PP tightening?
Anyone have any ideas I haven't thought of, any advice, or had this happen to them?
I've been working on the thing for 12 hours straight and I'm tapped out for now. My next plan of action is to bolt the thing back up and try it again, then I'm going to shorten the bolts by a couple threads and see what happens. Then I'm going to yell more bad words.
Background -
I've got an ACT HD Pressure Plate and an HPF Bronze 6-puck unsprung clutch disk that I am replacing my stock clutch/PP with. I had the flywheel machined by one of the best shops in FL with the correct step, they took care of the flywheel dowels. I followed the TSRM, threads from this forum, and common sense carefully and completely with the exception of over-torquing some bolts past TSRM specs.
I got all OEM Toyota parts and replaced the flywheel bolts, pilot bearing, rear main seal, and throwout bearing. I replaced the Redline fluid with Torco SGO.
Problem -
Car has a drivetrain vibration/unbalance from first startup after install. Doesn't stop with RPM change or clutch release engagement. It's hard to explain, but the engine has a quick repeating up and down, like what you would expect with a pressure plate out of balance. Visually, I can't really see anything obviously out of alignment when the assembly is turning or stopped, but it probably doesn't take much to create the vibration/balance issue I'm getting. I took the clutch fork out and took the PP off the flywheel again, everything looks great.
Question: Does the PP usually slide onto the flywheel dowels easily? I cannot get the pressure plate to interface with all three dowels without persuasion, like working the 2nd or 3rd dowel with tapping on the PP and tightening the pressure plate bolts strategically to get the dowels in the PP.
The first time I installed the PP, I just assumed this was normal to hold the clutch tightly in place. Now after the problem I'm not sure. I'm not sure if it matters because the bolts all go in fine.
Possible Solutions-
These are the things I think could be causing the problem.
- Pressure plate bolt length and machined flywheel. After thinking about it for a bit, my first thought was maybe the bolts for the pressure were too long now that the flywheel has been machined. They could be bottoming out and creating the illusion the PP is tight, but it isn't. I tested the bolts with a sharpie mark and they are damn close to being too long, but they tested OK by a slim margin. Still possible maybe? The PP looks tight against the flywheel.
- Unbalanced pressure plate from ACT. Does this ever really happen?
- Something funky on the first PP install. I guess this is the "I dunno, but I hope it magically works this time after not changing anything" solution. Maybe something didn't sit right with my PP tightening?
Anyone have any ideas I haven't thought of, any advice, or had this happen to them?
I've been working on the thing for 12 hours straight and I'm tapped out for now. My next plan of action is to bolt the thing back up and try it again, then I'm going to shorten the bolts by a couple threads and see what happens. Then I'm going to yell more bad words.
