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You need 1" of free play at the pedal when using finger pressure. Too much play will not release the clutch and it will grind going into gear. Too little play can allow slippage and the resulting heat damage.
Check your adjustment first and remember to put transmission in a forward gear before trying reverse.
Does your "Z" bar have multiple holes drilled in it for the mounting point of the firewall clutch rod? I have drilled a lower attachment point on mine. That will cause the lower rod to the throw out barring arm to move farther. You can also buy heim end lower rods and then you can adjust the preload on the throw out arm to bring it within say .060 of the PP fingers
I'll have to tweak that tomorrow. Funny - I thought I had followed the procedure to the letter
You probably did follow the instructions- but each clutch is slightly different. very minimal, but different. Some things just need to be tweaked a bit for perfection.
There are two throw out bearings for GM cars. One is for the Corvette and the other is for passenger cars. If you used the passenger car bearing, you will experience the problem you are having. Also, some of the new brand name clutch kits out of the box are bad. Check for a post by Lars on this very topic. It may be in the C-2 forum on this site. Good luck. Jerry
Does your "Z" bar have multiple holes drilled in it for the mounting point of the firewall clutch rod? I have drilled a lower attachment point on mine. That will cause the lower rod to the throw out barring arm to move farther. You can also buy heim end lower rods and then you can adjust the preload on the throw out arm to bring it within say .060 of the PP fingers
An update here... I think I will have to remove the Z-bar and drill an additional hole in it (How far down ? ) I adjusted the clutch rod to activate "sooner" and that seems to have gotten rid of the grinding. But you sill have to push that pedal way down the floor - seems excessive. In neutral, clutch out, you can also hear the throw out bearing still making contact.
Another thing I discovered is that not only the clutch pedal bump stop is missing, but it is also very bent. That explains the excessive pedal play and in an easy fix.
I would be very reluctant to drill a new hole in the Z bar as this may greatly affect the geometry and pedal effort. The problem could also be that the pivot ball stud is not the correct height. Different height ball studs are available as well as adjustable ones. The other option and in my opinion the best option is the above mentioned adjustable linkage with the HEIM joints. This is what I have and makes it very easy to adjust both legs of the clutch linkage (top and bottom). You can dial in the 'geometry' so that at max pedal push the upper part of the Z bar is nearly vertical … if this makes sense.
An update here... I think I will have to remove the Z-bar and drill an additional hole in it (How far down ? ) I adjusted the clutch rod to activate "sooner" and that seems to have gotten rid of the grinding. But you sill have to push that pedal way down the floor - seems excessive. In neutral, clutch out, you can also hear the throw out bearing still making contact.
Another thing I discovered is that not only the clutch pedal bump stop is missing, but it is also very bent. That explains the excessive pedal play and in an easy fix.
You should not hear any bearing contact. Not sure that is what you are hearing.
I would be looking for any lost motion in the linkage.
An update here... I think I will have to remove the Z-bar and drill an additional hole in it (How far down ? ) I adjusted the clutch rod to activate "sooner" and that seems to have gotten rid of the grinding. But you sill have to push that pedal way down the floor - seems excessive. In neutral, clutch out, you can also hear the throw out bearing still making contact.
Another thing I discovered is that not only the clutch pedal bump stop is missing, but it is also very bent. That explains the excessive pedal play and in an easy fix.
Three choices for me! It was hard to get a picture in there
Did you have the flywheel machined? Is the adjustment at max adjustment? If yes to both of the questions then then your problems is a small amount of material removed from the flywheel. Will cause an you to have no adjustment left on the upper rod to get the free play correct. As other have suggested the pivot stud needs to be made longer use 3729000.
Did you have the flywheel machined? Is the adjustment at max adjustment? If yes to both of the questions then then your problems is a small amount of material removed from the flywheel. Will cause an you to have no adjustment left on the upper rod to get the free play correct. As other have suggested the pivot stud needs to be made longer use 3729000.
My old flywheel is a heavy paper weight at a machine shop who has it for months and never bothered to call me and inform me that the piece was too big for their machines.
This is a new flywheel I don’t recall having this sound before. It’s not super loud. Yes get it only in neutral with the clutch pedal released.
I’m in London for the week. When I get back I’ll test by putting in neutral and disconnecting the clutch pedal to bring fork and throw out bearing as far as possible away from finger springs. Let’s see if anything changes.
The throw out bearing is correctly installed. The only thing that I noticed was that its restraining clip felt a bit weak.
You should not hear the throwout bearing at all if you have ANY pedal clearance at all.
What you CAN hear is the counter gear cluster and all the forward gears meshing and spinning around while you have your foot off the clutch in neutral.
1. Chevrolet has used only two sizes of throwout bearings for decades - 1-7/8" for passenger cars and trucks (flat-finger clutches), and 1-1/4" for Corvettes (bent-finger clutches). 2. The ONLY clutch fork ball stud that's "correct" is GM #3729000, 1-1/2" long. The other one which you will sometimes see, GM #3887159, 1-3/8" long, was released in error for '66, and after hundreds of field failure reports, was cancelled and replaced in production by the good old #3729000 stud on April 4, 1966, which remained in production through the mid-80's. Check and verify that you have the correct length ball stud. If you have the correct ball stud, be aware that aftermarket pressure plates (or machined/surfaced flywheels) will often require the use of a ball stud that's about 1/8" longer that the stock ball. We install the Lakewood adjustable ball (part number 15501) on almost every clutch job we do to assure proper geometry. If you set the adjustable ball up to produce a ball height 1/8" taller than the stock ball, you will usually be in good shape.
What you CAN hear is the counter gear cluster and all the forward gears meshing and spinning around while you have your foot off the clutch in neutral.
Hmmmm. Now that is interesting. So all this might be Much Ado About Nothing.
Seems like I just need to carefully adjust the clutch pedal and be done with it.
Not sure if you aware but he has a mechanical linkage clutch not hydraulic.
I was referring to the transmission fluid. He has a bit of noise coming from the gear box when in neutral. Could be low on fluid or just wear on the input shaft rollers or the counter gear needle bearings.
09-05-2019, 05:17 AM
Clutch pedal adjustment...
) I adjusted the clutch rod to activate "sooner" and that seems to have gotten rid of the grinding. But you sill have to push that pedal way down the floor - seems excessive. In neutral, clutch out, you can also hear the throw out bearing still making contact.
