[ChevJerico]

http://img392.imageshack.us/my.php?image=img007724xg.jpg
http://img392.imageshack.us/my.php?image=img007523da.jpg
http://img376.imageshack.us/my.php?image=img01783bs.jpg

I don't really know what to check next, except to re-verify bellhousing alignment for the umpteenth time. You guys see anything wrong with my fork or stud ball???? In the pics above the throwout bearings is resting on the PP springs,,,,fork is new GM for 70 Chevelle.

Oh yeah........one other thing! Where does your clutch release at? Mine seems to start releasing a 1/3 off the floor, I'm thinking my old 442 was closer to the top????

Thanks!

 

[Elusive_R]

I don't know the specific problems that you're having, but it seems like everything is where it should be. It looks like you have an aftermarket bellhousing and possibly a Centerforce clutch? Is the ball height correct? I don't think the throwout is supposed to be on the springs, though - there should be some air gap there.

When I still had the mechanical linkage on my Elky, the clutch would not release until about 1/3 off the floor like you said yours did.

Good luck!
Ryan

 

[loader1]

HJ,

Let me ask you this, how much free play do you have in your pedal? Everything looks good to me. When you say it releases 1/3 off the floor, do you mean that the car starts to move when you let the pedal 1/3 out from fully depressed to the floor?

 

[COPO]

Depending on how you like the free play there are 2 different settings.

1. (freeplay 2-2.5") Car starts to move when the clutch pedal is close to the floor. If set this way then when you change gears you will need to make sure you go all the way to the floor with the pedal or you'll be hearing a grind.

2. (freeplay 1-1.5") Car starts to move when the pedal is 1/2 way up. This advantage is that when you go to shift gears you don't need to go all the way to the floor. This is good for drag racing, cause you only have to go 3/4 down to the floor to shift gears.

Try both ways see what you like best.

 

[ChevJerico]

Well I have the dreaded clutch release problem that a lot of CF DF users seem to have. Except I ruled out my CF when I installed a NAPA clutch. I've since put the CF back in, been fighting this for over a year now in between a defective piston and engine rebuild.

When cold the shifter seems to move freely and goes into gear smoothly, but this doesn't last long. After a short period shifting becomes notchy and stiff, not horribly bad and okay for normal driving but impossible to do any speed shifting. Almost always get the reverse gear crunch, even after holding the clutch pedal in for 5-10 secs to let the cluster spin down. If I park it for 15 minutes or so, it seems okay for a short period!

I bought the clutch fork new from GM so I was hoping someone could ID it as correct for 70 Velle and that I have the clutch ball adjusted correctly........fork slightly forward when throwout bearing contacts springs. Probably wouldn't matter anyway because for test purposes I adjusted out all the freeplay and then some and never achieved any kind of consistent release. Currently I have an 1" of freeplay.

I've checked everything you can think of...........this $hitt is gettin old!!!!!!!!!

 

[ToocoolZ28]

Where did you get the throwout bearing? I had the same problems, I replaced EVERYTHING, clutch, all linkage, pedal bushings, throwout bearing 4 times, fork, balls and finally the transmission. It turned out to be the throw out bearings, they were all the same brand NAPA. I finally bought one at O'riellys and it fixed it completley. The front edge of the bearing was very sharp and was digging into the bearing retainer on the front of the transmission, it was obvious after I put the new transmission in. I fought this for 3 years.
Ron

 

[loader1]

HJ,

The reason I asked about your freeplay was that I had forgotten your previous posts on this problem. I am running same set up as you, Lakewood, CFDF, w/aftermarket fork that is supposed to be stronger. Like I said before, looking at your pics, everything looks good to me. I can't address whether or not your fork should look different for your 70 as I don't know that. You have a clear understanding of how it's supposed to work so I think you have done everything that you can do as far as the clutch set up.
You say it gets notchy and stiff, w/ some reverse gear crunch. In my car I will occasionally get some reverse gear crunch, but only once in a while and I attribute it to the nature of the beast. You say it shifts ok but can't be speed shifted.
Now I don't want to open a can of worms here, and maybe WALLY can get in on this, as I'm not an expert but maybe you're chasing the wrong problem. So my next question would be, what is the condition of your tranny?
Before you start throwing things , I'm only asking because I rebearinged and replaced all synchros and gears that looked suspect myself using the factory overhaul manual. My tranny feels smoother when cold than it does after warming up. But, when I go to the track I pull the gears HARD,...no grind, no crunch, no misses (lucky),...can only be described as total abuse. I'm thing maybe your synchros are worn and not slowing things down like they should.
Sorry to bring it up, but it's the only thing that comes to mind after reading your post, looking at pics, and knowing that you understand how your clutch works. I think you're badgering yourself over the clutch, when you really have everything right there. Thought about this all night.

 

[ChevJerico]

Where did you get the throwout bearing? I had the same problems, I replaced EVERYTHING, clutch, all linkage, pedal bushings, throwout bearing 4 times, fork, balls and finally the transmission. It turned out to be the throw out bearings, they were all the same brand NAPA. I finally bought one at O'riellys and it fixed it completley. The front edge of the bearing was very sharp and was digging into the bearing retainer on the front of the transmission, it was obvious after I put the new transmission in. I fought this for 3 years.
Ron

Ron, I'm not sure I'm following you, where exactly on the bearing retainer was it hanging up??? Are you saying when you push the clutch pedal in,,, the bearing would not move all the way forward,,, or would not move backwards when releasing the clutch pedal?????

John

 

[ToocoolZ28]

The bearing wouldnt slide back and forth, mostly when I pushed the clutch in. It was hanging up on the bearing retainer on the transmission. If I look at the NAPA bearing it has a very sharp edge on the inside where it slides back and forth and dug into the retainer. The O'Rielly's bering has a rolled edge on the front that prevents it from digging in. When I had the Muncie in the car it was worse, maybe because the bearing retaing was already scarred up, at low speeds it wouldnt downshift to 1st or would make a loud squeeling sound.

I know, clear as mud but I hope it helps.
Ron

 

[BillK]

John,

The bearing retainer might be worn enough to cause the problem. Also, are you putting any type of grease or lubricant on the retainer to allow the throwout bearing to slide easily ? I always put a light coat of grease on it. I had a 83 Chevy 4WD Pickup that had the same problem. I got to where I could get under the truck and squirt some oil on the bearing when it started acting up and it would be good for a few months.
One thing you should do is try to get someone to help you. Have one person in the car slowly pushing in the clutch while you watch it from under the car. Its a lot easier to see things happen that way, rather than trying to guess what the problem is.

 

[ChevJerico]

HJ,

The reason I asked about your freeplay was that I had forgotten your previous posts on this problem. I am running same set up as you, Lakewood, CFDF, w/aftermarket fork that is supposed to be stronger. Like I said before, looking at your pics, everything looks good to me. I can't address whether or not your fork should look different for your 70 as I don't know that. You have a clear understanding of how it's supposed to work so I think you have done everything that you can do as far as the clutch set up.
You say it gets notchy and stiff, w/ some reverse gear crunch. In my car I will occasionally get some reverse gear crunch, but only once in a while and I attribute it to the nature of the beast. You say it shifts ok but can't be speed shifted.
Now I don't want to open a can of worms here, and maybe WALLY can get in on this, as I'm not an expert but maybe you're chasing the wrong problem. So my next question would be, what is the condition of your tranny?
Before you start throwing things , I'm only asking because I rebearinged and replaced all synchros and gears that looked suspect myself using the factory overhaul manual. My tranny feels smoother when cold than it does after warming up. But, when I go to the track I pull the gears HARD,...no grind, no crunch, no misses (lucky),...can only be described as total abuse. I'm thing maybe your synchros are worn and not slowing things down like they should.
Sorry to bring it up, but it's the only thing that comes to mind after reading your post, looking at pics, and knowing that you understand how your clutch works. I think you're badgering yourself over the clutch, when you really have everything right there. Thought about this all night.

Mike I wish, I've already had three transmissions in the car! The first was a Pick-N-Part special I got for 69.99, back then I was thinking it was a worn transmission. Everything from the engine back has since been changed. The transmission I have now is rebuilt and feels the same way as the junkyard special.

Prior to the latest transmission, I had the Liberty pros-shifted box in with NO synchros. The release problem was real obvious. It was almost impossible to get into any gear from a stop, unless the car was cold.

 

[loader1]

HJ,

Man, I've been thinking about this and the only other thing that comes to mind is whether or not you might have changed something like a different Z bar or hole position, resulting in the throwout bearing not moving far ENOUGH. But I'm sure you would have thought of that. Sorry, I'm out of ideas, hope you find your problem.

 

[ChevJerico]

John,

The bearing retainer might be worn enough to cause the problem. Also, are you putting any type of grease or lubricant on the retainer to allow the throwout bearing to slide easily ? I always put a light coat of grease on it. I had a 83 Chevy 4WD Pickup that had the same problem. I got to where I could get under the truck and squirt some oil on the bearing when it started acting up and it would be good for a few months.
One thing you should do is try to get someone to help you. Have one person in the car slowly pushing in the clutch while you watch it from under the car. Its a lot easier to see things happen that way, rather than trying to guess what the problem is.

Bill, one of the bearings I had came with some type of really slick grease, grey in color. The others were dry, I can't remember if I put any on the current one or not but think I did. I'll try the oil. No grease on the pilot bushing either.

My 12 year old son has been helping with clutch pedal pushing duty and helping with the upper bellhousing bolts. Everything looks good to me. Clutch is moving and I've checked disc air gap cold and hot.

Anybody need a left nut, I willing to trade mine for someone to figure this out

 

[ChevJerico]

HJ,

Man, I've been thinking about this and the only other thing that comes to mind is whether or not you might have changed something like a different Z bar or hole position, resulting in the throwout bearing not moving far ENOUGH. But I'm sure you would have thought of that. Sorry, I'm out of ideas, hope you find your problem.

Yeah I've measured fork travel at both ends and it's within spec, plus I ruled that out anyway when I adjusted out all freeplay and then some.

Think I need to start a support group for poor saps like me that have clutch release problems.

 

[blm]

HJ: What kind of ball height do you have? It looks like it is threaded down pretty far. I just went through a centerforce installation and had some disengage problems. I have a 69 and can't recall the part number but I listed it in a post I had recently for a free play question. I noticed that my fork sat closer to the front of the bellhousing than yours does when I got everthing working properly. I do have a 621 GM bellhousing and that could make a difference as far as where the fork appears to sit. I do know that every post I saw kept calling for a 4.75 pivot ball height and that did not work for me. Mine did not work until my ball height was a hair over 5 inches.

 

[ChevJerico]

HJ: What kind of ball height do you have? It looks like it is threaded down pretty far. I just went through a centerforce installation and had some disengage problems. I have a 69 and can't recall the part number but I listed it in a post I had recently for a free play question. I noticed that my fork sat closer to the front of the bellhousing than yours does when I got everthing working properly. I do have a 621 GM bellhousing and that could make a difference as far as where the fork appears to sit. I do know that every post I saw kept calling for a 4.75 pivot ball height and that did not work for me. Mine did not work until my ball height was a hair over 5 inches.

To get more then 4.75", I would have to screw the ball in deeper moving the fork further back???? I could see trying less then 4.75"


How did you measure ball height?

Thanks

 

[ChevJerico]

Where did you get the throwout bearing? I had the same problems, I replaced EVERYTHING, clutch, all linkage, pedal bushings, throwout bearing 4 times, fork, balls and finally the transmission. It turned out to be the throw out bearings, they were all the same brand NAPA. I finally bought one at O'riellys and it fixed it completley. The front edge of the bearing was very sharp and was digging into the bearing retainer on the front of the transmission, it was obvious after I put the new transmission in. I fought this for 3 years.
Ron

Ron,

My clutch pedal feels smooth, could you feel the digging in the pedal?

My bearing retainer looks normal to me. I don't know when one is considered worn out or not?????

John

 

[blm]

I didn't have the Centerforce instructions to confirm but from everything I could gather to measure ball height you measure from the flat section of the pivot ball ( the side facing the transmission ) through the rounded portion of the pivot ball to the front face of the bellhousing. To get the front face of the bellhousing lay a straight edge across the front edge of bellhousing. Naturally the bellhousing has to be removed from the vehicle to get this measurement. As I said before they call for a 4.75 inch measurement for those dimentions. At 4.75 inch mine did not have any freeplay and the throw out was wedged against the pressure plate fingers. At 5.25 inches I had disengage problems. I had to make small adjustments in the pivot ball, then install the bellhousing, check my throw out and fork position and remove bell housing again. I think it took three or four bell housing installations with pivot adjustments each time to get it right. As I searched through the archives I think people are taking pivot height measurements from different areas.The 4.75 measurement may have worked for me if I measured from the tip of the pivot ball to bellhousing face, but I don't believe that is where is is supposed to be taken from.

 

[Guest]

Yeah I've measured fork travel at both ends and it's within spec, plus I ruled that out anyway when I adjusted out all freeplay and then some.

Think I need to start a support group for poor saps like me that have clutch release problems.

I got on the phone this morning and called Tech Support at CF and explained your problem.

We went through all the stuff you have done. I asked how much travel is needed to release the disk the required .030 after it engages the the fingers of the clutch, 3/8 of an inch. I also aked about the flywheel thickness, should be .960 when new measured from the clutch face to the back of the flange that bolts to the crank.

Couple of other things, no grease of any type on the bronze bushing and they said to use a special high temp grease made for disk brakes on the release bearing where it rides on the front bearing retainer.

I don't know what kind of flywheel you have but different brands are a different thickness, up to .100 different.

 

[JodysTransmissions]

http://img392.imageshack.us/my.php?image=img007724xg.jpg
http://img392.imageshack.us/my.php?image=img007523da.jpg
http://img376.imageshack.us/my.php?image=img01783bs.jpg

I don't really know what to check next, except to re-verify bellhousing alignment for the umpteenth time. You guys see anything wrong with my fork or stud ball???? In the pics above the throwout bearings is resting on the PP springs,,,,fork is new GM for 70 Chevelle.

Oh yeah........one other thing! Where does your clutch release at? Mine seems to start releasing a 1/3 off the floor, I'm thinking my old 442 was closer to the top????

Thanks!

Hello John,

Still having problems..............grrrrrrrrrrrrrrrrrr!

I looked at your 3rd picture and it seems you are not over the 90 degree angle which is needed for the proper geometry. Almost like your pivot ball height is too short. I am assuming you had the throw out bearing against the pressure plate fingers in the pic?

Regards, Jody