Replacing the Clutch, and diagnosis of failure
03-31-10, 12:29 PM
#51
Waffles - hmmm good
iTrader: (1)
a hard time pushing it further by hand. Did you look thru the inspection plate
to see if all the peices are in there?
03-31-10, 01:00 PM
#52
Did you ever adjust your pedal rod? Remember your old disc was worn down to nothing. The new disc is very thick. You must adjust your clutch pedal rod for proper operation.
Elongate the rod. Why? Because your old clutch, being super thin, caused the spring fingers of the pressure plate to lift away from the disc. You must have needed to shorten your rod on occasion as your friction point steadily inched its way up from the middle to the top of its travel; adjusting the rod allows you to keep using a worn out disc for a while, but is not recommend due to eventual rivit contact.
If the above doesn't solve your problem, look at clutch hydraulics next. Check for leaks. Look inside the slave boot for fluid. If any is found, time for a rebuild kit or replace the slave and get a nice new braided stainless hose. Also rebuild or replace the master because when one goes, the other goes right after. This saves you from pulling the engine and tranny together (still don't understand why you have to pull both but I guess others do it that way and it works for them) to check on the clutch disc and pressure plate, throwout bearing directly.
Elongate the rod. Why? Because your old clutch, being super thin, caused the spring fingers of the pressure plate to lift away from the disc. You must have needed to shorten your rod on occasion as your friction point steadily inched its way up from the middle to the top of its travel; adjusting the rod allows you to keep using a worn out disc for a while, but is not recommend due to eventual rivit contact.
If the above doesn't solve your problem, look at clutch hydraulics next. Check for leaks. Look inside the slave boot for fluid. If any is found, time for a rebuild kit or replace the slave and get a nice new braided stainless hose. Also rebuild or replace the master because when one goes, the other goes right after. This saves you from pulling the engine and tranny together (still don't understand why you have to pull both but I guess others do it that way and it works for them) to check on the clutch disc and pressure plate, throwout bearing directly.
03-31-10, 01:18 PM
#53
Now for a little reassurance. Everything looks fine in this picture.
The aluminum spacers appear to be installed correctly. The pressure plate spring fingers look flat across from each other, which is a good sign that your disc is new and thick. Everything appears to be in order.
The problem has got to be the rod or hydraulics.
I mention this because it is relevant to your situation in that I recently installed an engine in my '81 which had a freshly resurfaced flywheel (so the step is as close to brand new as possible), the disc is thick and very low mileage, the pressure plate has very little wear. My car's old setup had a really worn disc, a really worn flywheel and a moderately worn pressure plate. All three added up to quite a bit of clutch pedal rod adjustment. Once the new setup went in, my first press of the pedal resulted in nothing. I knew what I had to do. Adjusted the rod out (lengthened) until it brought the pedal up to a normal height. Tried again and booya!
The aluminum spacers appear to be installed correctly. The pressure plate spring fingers look flat across from each other, which is a good sign that your disc is new and thick. Everything appears to be in order.
The problem has got to be the rod or hydraulics.
I mention this because it is relevant to your situation in that I recently installed an engine in my '81 which had a freshly resurfaced flywheel (so the step is as close to brand new as possible), the disc is thick and very low mileage, the pressure plate has very little wear. My car's old setup had a really worn disc, a really worn flywheel and a moderately worn pressure plate. All three added up to quite a bit of clutch pedal rod adjustment. Once the new setup went in, my first press of the pedal resulted in nothing. I knew what I had to do. Adjusted the rod out (lengthened) until it brought the pedal up to a normal height. Tried again and booya!
03-31-10, 01:35 PM
#54
Looking over this entire thread, I see you have an '84-'85 chassis by the look of your strut towers. This means your clutch pedal has longer travel than an '83 or older, and you have what I call a helper spring. This helper spring causes your pedal to drop to the floor and stay there when the clutch master's cylinder doesn't come back on its own either due to a vacuum in the system (as in the slave is out too far) or the spring inside the master is too weak, or its kinda rusty or gunked up inside the bore. This happened on the red '84 GSL I worked on for a while in '08 to '09 (rust from sitting since '94). We replaced both clutch hydraulics because they were rusted up. I tried several different pressure plate/disc/flywheel combos on various engines and the hydraulics never wavered. We also got a stainless braided hose.
Hint hint.
Hint hint.
04-02-10, 04:30 AM
#55
Lives on the Forum
Thread Starter
Hmm, clutch hydraulics were never touched, I just unbolted the slave from the tranny. Both the slave and master are new as of a year ago.
I really don't think this is related to the hydraulics, because I can reach down and move the shift fork with no resistance, sliding the throwout bearing back and forth with ease.
I will try to pull the inspection plate today after work and see what is going on in there.
Thanks for the input guys...
I really don't think this is related to the hydraulics, because I can reach down and move the shift fork with no resistance, sliding the throwout bearing back and forth with ease.
I will try to pull the inspection plate today after work and see what is going on in there.
Thanks for the input guys...
04-04-10, 12:25 AM
#56
That's really strange. It should be working. The pressure plate in the picture above appears to be set up properly. At least you didn't screw up bigtime like this guy did.
https://www.rx7club.com/album.php?al...pictureid=4049
You might have to turn the brightness up on your monitor. Too bad the guy didn't turn his "brightness" up.
https://www.rx7club.com/album.php?al...pictureid=4049
You might have to turn the brightness up on your monitor. Too bad the guy didn't turn his "brightness" up.
04-04-10, 10:18 AM
#57
I was just reading through this and noticed that you were told not to use loctite?
I was told by many mechanics and my teachers that if it came from the assembly line with loctite make sure you use it. Especially on a flywheel that hits up to 8k RPM. The vibrations can loosen the nut hence why your supposed to use Red loctite. Its not hard at all to remove, all you need is a torch and you burn the Loctite away and it zips right off.
I was told by many mechanics and my teachers that if it came from the assembly line with loctite make sure you use it. Especially on a flywheel that hits up to 8k RPM. The vibrations can loosen the nut hence why your supposed to use Red loctite. Its not hard at all to remove, all you need is a torch and you burn the Loctite away and it zips right off.
04-05-10, 10:32 AM
#59
Wasn't it you who said use RTV instead? Either way doesn't matter if it was or not I was just expressing concern. I might have just misread.
EDIT- I just found and fully read your post, it makes a lot of sense and I'm sure you know what your talking about. I apologize if I insulted you in anyway I didn't mean to, but I do always use loctite anyway makes me feel better.
EDIT- I just found and fully read your post, it makes a lot of sense and I'm sure you know what your talking about. I apologize if I insulted you in anyway I didn't mean to, but I do always use loctite anyway makes me feel better.
04-05-10, 01:22 PM
#60
Lives on the Forum
Thread Starter
I had to go to Chicago this past weekend, so I didn't have a chance to look her over. If I get home early enough tonight, I'll pull that inspection plate off and take a look.
I still don't understand how the throwout bearing could have full movement with zero resistance. How could it not be coming into contact with the PP?
I still don't understand how the throwout bearing could have full movement with zero resistance. How could it not be coming into contact with the PP?
04-08-10, 03:09 PM
#61
Lives on the Forum
Thread Starter
Update:
Bad news; I got back from Chicago with a cold to end all colds. Misery factor is straight through the roof! I feel like I've been run over by a truck that was leading a pack of elephants. How can somebody feel this lousy and still be alive?
Good news; I crawled my way out to the garage today and stared at my motor, just dreading the fact that I had to pull it back out again. Tried the clutch again, damn thing when straight to the floor. Fudge!!! Looked at the slave cylinder, and the piston appeared to be well extended, but there was still about 1/2 inch between it and the shift fork.
Got pissed off, figured I had nothing to loose, and just started cranking back and forth on the clutch pedal working it back and forth like a maniac. Well, after about 4 or 5 compressions, the damn hydraulics woke up, I heard the slave piston pop into position on the shift fork, and all of a sudden I've got a great feeling clutch again!!!!
So then I crawled my way back into bed for a nice nap...
I figure that after sitting idle for a few months, the clutch hydraulics just forgot what their function in life was. In the end, she just needed a little love and attention. lol.
So now, all of a sudden I'm back on track for DGRRX! If I ever get over this damn cold, that is....
Bad news; I got back from Chicago with a cold to end all colds. Misery factor is straight through the roof! I feel like I've been run over by a truck that was leading a pack of elephants. How can somebody feel this lousy and still be alive?
Good news; I crawled my way out to the garage today and stared at my motor, just dreading the fact that I had to pull it back out again. Tried the clutch again, damn thing when straight to the floor. Fudge!!! Looked at the slave cylinder, and the piston appeared to be well extended, but there was still about 1/2 inch between it and the shift fork.
Got pissed off, figured I had nothing to loose, and just started cranking back and forth on the clutch pedal working it back and forth like a maniac. Well, after about 4 or 5 compressions, the damn hydraulics woke up, I heard the slave piston pop into position on the shift fork, and all of a sudden I've got a great feeling clutch again!!!!
So then I crawled my way back into bed for a nice nap...I figure that after sitting idle for a few months, the clutch hydraulics just forgot what their function in life was. In the end, she just needed a little love and attention. lol.
So now, all of a sudden I'm back on track for DGRRX!
If I ever get over this damn cold, that is....
04-10-10, 06:46 AM
#66
Lives on the Forum
Thread Starter
I hope to make some more progress on this today. But I might run out to grab a 2000 Lexus LS400 Platinum Edition for the wife, so that might slow me down a bit (tranny in the Bimmer is giving me fits).
I looked her over again this morning, and there's really not much more to be done. No reason I shouldn't have her on the road today, other than the fact that I'm half dead. lol.
I'll keep you guys posted.
I looked her over again this morning, and there's really not much more to be done. No reason I shouldn't have her on the road today, other than the fact that I'm half dead. lol.
I'll keep you guys posted.
04-12-10, 10:05 AM
#68
Lives on the Forum
Thread Starter
Happy day guys...
Guess what I drove in to work today? lol. I just have to say, what an awesome car. After being down since October of last year, she took back to the road like she'd only been parked for an hour. No issues, no hickups, no hassles at all.
Jeff- The clutch feels great! Nice, smooth engagement, and the pedal feel is (I think, because it's been a while) slightly lighter than the RB Street/Strip that was on there before. I think the car feels quite a bit peppier in the lower gears due to the new flywheel, but again, its hard to tell because its been so long since I last drove her. Also, obviously I can't beat on her while breaking in the new clutch. I figure she should be broken in just about the time I hit the Tail of the Dragon. Yeehaw!!!
I'll need to lengthen the rod a tad on the pedal, right now the clutch doesn't disengage until right before the pedal bottoms out. But no biggie there.
Tonight I need to swap out the front struts, lube the chassis, and that's about it other than packing her up for the trip to DGGRX. Plan to leave Wednesday night, so this is all happening just in time.
Guess what I drove in to work today? lol. I just have to say, what an awesome car. After being down since October of last year, she took back to the road like she'd only been parked for an hour. No issues, no hickups, no hassles at all.
Jeff- The clutch feels great! Nice, smooth engagement, and the pedal feel is (I think, because it's been a while) slightly lighter than the RB Street/Strip that was on there before. I think the car feels quite a bit peppier in the lower gears due to the new flywheel, but again, its hard to tell because its been so long since I last drove her. Also, obviously I can't beat on her while breaking in the new clutch. I figure she should be broken in just about the time I hit the Tail of the Dragon. Yeehaw!!!
I'll need to lengthen the rod a tad on the pedal, right now the clutch doesn't disengage until right before the pedal bottoms out. But no biggie there.
Tonight I need to swap out the front struts, lube the chassis, and that's about it other than packing her up for the trip to DGGRX. Plan to leave Wednesday night, so this is all happening just in time.
04-12-10, 02:55 PM
#70
The reason for your pedal engaging so low is because you used a street strip pressure plate with a stock disc. Just adjust the rod and you're fine. The SS p-plate is sprung a little differently than a stock one, to work better with a non-marcel disc such as the RB HD disc or a puck style, to cause the engagement point to be somewhere in the middle.
There are several combinations one could try, with different results.
SS p-plate with non-marcel disc = engagement somewhere in the middle (typical RB setup)
SS p-plate with stock marcel disc = engagement near the floor (kentetsu's setup)
stock p-plate with non-marcel disc = engagement near the top of travel (this feels really bad, not recommended)
stock p-plate with stock marcel disc = engagement somewhere in the middle (typical stock setup)
I hope this info helps somebody.
The SS p-plate is sprung a little differently than a stock one, to work better with a non-marcel disc such as the RB HD disc or a puck style, to cause the engagement point to be somewhere in the middle.There are several combinations one could try, with different results.
SS p-plate with non-marcel disc = engagement somewhere in the middle (typical RB setup)
SS p-plate with stock marcel disc = engagement near the floor (kentetsu's setup)
stock p-plate with non-marcel disc = engagement near the top of travel (this feels really bad, not recommended)
stock p-plate with stock marcel disc = engagement somewhere in the middle (typical stock setup)
I hope this info helps somebody.
04-12-10, 04:04 PM
#72
You tell me. You installed it.
I don't know Exedy parts by their part numbers. Did Billy send you a stock style disc or an HD style? Did the friction material surfaces have any springiness between them? Or were they rivited solidly to the disc like your old dead HD disc? Just curious so I can compile more information. It's my guess it's a stock style disc and that's why it engages where it does on your SS pressure plate, near the floor.
I don't know Exedy parts by their part numbers. Did Billy send you a stock style disc or an HD style? Did the friction material surfaces have any springiness between them? Or were they rivited solidly to the disc like your old dead HD disc? Just curious so I can compile more information. It's my guess it's a stock style disc and that's why it engages where it does on your SS pressure plate, near the floor.