oledave60

I am trying to finish a swap and have run into a problem with the clutch linkage. From ebay I have the correct bell housing, clutch fork, z bar, rod from fork to z bar, rod from z bar to pedal and original clutch/brake pedals. The rod from the fork to the z bar has no adjustment, so when it is hooked up the rod from the pedal is too long even with the nuts all the way up.

Has anyone else run into this problem and what have I done to screw it up? I hate to start cutting rods when it is all factory original.

And yes I have an AIM and I am using it.

Thanks, Dave

mvette76

do you have the right throw out bearing?

billsfan

I learned (from experience) that you cannot put a regular chevy clutch and throwout bearing in a Corvette. The Vette uses a shorter throwout bearing.

oledave60

I got a ZOOM 11" clutch kit from Summit and their description says with a "standard" throwout bearing. It has the raised fingers on the pressure plate and I read that with these you use the shorter bearing. I guess today I will pull the trans and try to see what the problem is. I just don't feel like I should have to start cutting rods. Thanks, Dave

oledave60

Here is the lower rod installed and no springs attached. The fork is about 5/8" from touching the bell housing. It is about as far forward as it will go and at this point seems to be just contacting the pressure plate.



This is the upper rod and the clutch pedal is all the way up against the rubber stop. The z-bar is just about straight up and down.

Does any of this look not correct? Thanks for your help, Dave

oledave60

Pulled the trans and I just don't see anything that I could change to put the fork in a different position and lengthen the space between fork and z-bar.

From the p plate fingers to the outside face of bell housing is 2 3/8", the trans bearing retainer is 1/2" leaving 1 7/8". The release bearing is 1 1/4" which leaves 5/8" free play, which is about what I have.

Before I put this back together I would appreciate any and all suggestions. Thanks

Chucknorbid

Check your old parts to new parts/Height of pressure plate. If the throw out bearing is the same you might have a wrong pressure plate that is shorter than the new one. I see the rust spot where original placement of the rod was. And that is about correct.

oledave60

Thanks, I don't have any old pats to compare as I am doing an auto to manual swap.I called Summit and they said I may have a pressure plate for a truck, but they weren"t even sure if there was a difference between a truck and car. Said I would need to call back Monday.

redvetracr

there are three different C-2/3 Z-bars, two different short push rods and two different long pushrods, how do you know what you have?

Garys 68

Make sure you have the throwout bearing installed correctly.
See below for correct installation and geometry. Never know if the aftermarket clutch/PP is the ame depth.
I'm also assuming you have the pressure plate bolted down tight.
http://www.novak-adapt.com/knowledge/clutches-etc/

oledave60

According to Zip and other vendors the cross shaft and two rods are the same for 68 to 81. Mine is from a 72.

Bearing was installed correctly and pressure plate was installed with a torque wrench.

I really don't know where to go from here. Thanks, Dave

Garys 68

Doesn't look like you can get a shorter throwout bearing or fork pivot ball. If the pedal is mounted correctly, I'm guessing pressure plate depth issue.

oledave60

I think you are right about the pressure plate. I just can't find any depth measurements of different p plates.

3X2

You might want to look into this:
http://www.speeddirect.com/index.php...ucts/rod-links

if this helps, the picture is from Centerforce. I've played with linkage on my 69 for many years with different clutches. Ended up lengthening the lower rod by 3/4".

oledave60

Does anyone have a picture of their clutch fork installed and maybe an estimate of how much free play the throw out bearing has? Thanks, Dave

Chucknorbid

Hi Dave
I have a 1970 454. Here is a Pic of the Rod to Z Bar. This has a new McLeod Street/Strip 11" 10 spline clutch with self centering throw out bearing.It all came in the kit.I have a new pivot ball & clutch fork & new lower link rod.This is a diaphragm type clutch. The original clutch was a Delco. When I did the new clutch I laid the pressure flat and measured from the flat surface to the fingers to make sure they were the same. You do not have that luxury. I looked on the interweb to see if I could find a mechanical drawing of this dimension and could not find one. I am sure it is there some place. I am sending a pic of the Z bar position. I have done a few Vette clutches over the years and as I recall this is about normal position. I use a double nut on the adjuster. I have about 1/4" free play with the spring disconnected. Looking at your adjuster I think your pressure plate is to tall.
Chuck

donnie1956

I just did a auto to manual swap. Biggest difference is I have and LS. There is not a location on an LS engine block for the Z bar ball. I ended up using this rod so I had some adjustment on the bottom. http://www.ebay.com/itm/252169972928?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT

oledave60

Just as a follow up and one more question, this past weekend I pulled everything back out and could not find anything that looked out of place.

Yesterday I talked to the ZOOM tech and he was very helpful and spent a lot of time with me. He said that stock replacement clutches , pressure plates and release bearings are the same. He said that the only problem he had seen is on some SB the crank shaft mount can be different. He said the important measurement was from the face or end of the crank shaft to the pressure plate fingers with it installed. Mine is within specs (3.36")

So, I now have everything back together and my bottom linkage is still too long. I don't mind cutting it to fit, but does anyone have a measurement of theirs. Thanks, Dave.

carriljc

Just that one rod?

redvetracr

remember when I asked you if you had any C-2 parts? that rod above is from a C-2 NOT a C-3, the C-3 rod is shorter...