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hey all. I just dropped the engine in my car yesterday and bolted up the tranny. I seem to have an issue though with the clutch fork and play. I purchased a throwout bearing form the local performance store that had been around since the 60's and the guy was very knowledgeable. I purchased the clutch fork from GM classics. My old fork with a different bellhousing was more angled or curved. The one from GM classics was flater. I am attaching two picks of the old fork and the slot where the fork sits with the bearing which you can see pretty clear. There is barely any movement left before hitting the bellhousing with the flat fork once the bearing hits the pressure plate as you can see in the picture. I am sure I have the bearing on correct and the fork is attached properly to the ball on the housing. I have not attached the bellcrank or linkage yet but it seems there should be more room than what I have to release the pressure plate. Not sure how geometry plays into hear Anyone experience this before. Am I using the wrong fork I got from GM Classics. The bellhousing is the correct one for the Nova. 309 I believe.
 

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Assuming you have the correct height TO brg, (usually the tall TO for a flat finger diaphragm clutch) your problem is likely the in or out adjustment of the fork ball. It needs to be screwed in the direction the flywheel to give you more leverage and correct the clutch fork height.
Looks like you have an OEM bellhousing. Often the factory ball is not adjustable so you would then have to remove the bellhousing and install an aftermarket ball.
An example of an adjustable ball would be Summit part number: SUM-700110
 

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Chevy used a few different clutch fork balls studs and they vary in length. My understanding is they do not interchange, having different pitch threads, but who knows. The early Nova one (3790556) is supposed to be unique to Chevy II and almost 2" in total length. In 1968 they went to the common 3729000 which is ~1 1/2". There is also 3725240 (short) and 3769589 (Corvair). Maybe you have the wrong ball stud? If you search online by those numbers you will see pictures. And I agree the bellhousing looks correct.

The clutch fork you removed looks like the 3rd design they started using in the mid 70s.
 

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Chevy used a few different clutch fork balls studs and they vary in length. My understanding is they do not interchange, having different pitch threads, but who knows. The early Nova one (3790556) is supposed to be unique to Chevy II and almost 2" in total length. In 1968 they went to the common 3729000 which is ~1 1/2". There is also 3725240 (short) and 3769589 (Corvair). Maybe you have the wrong ball stud? If you search online by those numbers you will see pictures. And I agree the bellhousing looks correct.

The clutch fork you removed looks like the 3rd design they started using in the mid 70s.
Thanks. I think that may be it. Looks like the stud is supposed to be 1.75 in length and this one may be shorter. I took it out of my other bellhousing that ends in 621 that used to be on the car with a non chevy2 block. I guess I will be pulling the tranny out again to take a look. I do not want to have to remove the bell housing so hopefully I can do this without doing so.
 

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Assuming you have the correct height TO brg, (usually the tall TO for a flat finger diaphragm clutch) your problem is likely the in or out adjustment of the fork ball. It needs to be screwed in the direction the flywheel to give you more leverage and correct the clutch fork height.
Looks like you have an OEM bellhousing. Often the factory ball is not adjustable so you would then have to remove the bellhousing and install an aftermarket ball.
An example of an adjustable ball would be Summit part number: SUM-700110
You may be right. But I will get a stock stud that is the correct length. Thanks.
 

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Thanks. I think that may be it. Looks like the stud is supposed to be 1.75 in length and this one may be shorter. I took it out of my other bellhousing that ends in 621 that used to be on the car with a non chevy2 block. I guess I will be pulling the tranny out again to take a look. I do not want to have to remove the bell housing so hopefully I can do this without doing so.
If the Chevy II one really is unique as the parts book says, the one you took out of the other bellhousing would be wrong length. The 621 bellhousing uses the shorter "3729000" ball stud. Good luck and please do let us know how this works out. You will not be the last to encounter this issue.
 

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So I got the new pivot ball stud in and yes it was a 1/4" longer. Made all the difference in the world. Now I have a new problem which I did not notice originally. The clutch forks clip is tack welded off center and when I put the throwout bearing on it does not ride in the clip properly. As I was looking I can see the clip has more space on one side than the other so bearing does not center on the clip and is barely holding on one side. Now it looks like I am going to have to take the bellhousing off and pull the fork and order a new one. Hopefully GM Classics will just do an exchange. I go back to work Monday from vacation and was hoping to have this out of the way. Now time will be limited as to when I can work on the car. Still a ton of work to do and the tranny and engine was just a drop in the bucket and those are still far from being completed.

Now that I am going to have to remove the bellhousing I guess I will pull the clutch and replace the pilot bearing. It is the original one and there were no issues but now that is is coming apart I may as well do it Any tips on removing? I have heard of bearing grease to squeeze it out but prefer using something less messy. Maybe pep boys will have some sort of tool. I replaced it in my old engine and think I borrowed a tool from them or somewhere.

Thanks
Michael
 

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You have a self-aligning TO bearing. Are you sure you don't have it rotated in the fork so that the fork is pushing on the self-alignment "hump" thus not allowing the TO to center in the fork?
 

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i think it was one of the TV auto shows i saw them use bread to push out the old pilot bearing.
 

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Remember that the clip on the clutch fork is just kind of there to hold the bearing in place while you assemble. The center of the throwout rides on the nose cone of the trans and if that's in good shape, the throwout bearing won't go anywhere but where it's supposed to. The clips aren't the surface bearing the load between the throwout and the fork for moving the fork forward or rearward; they're there just to keep it kind of in place during assembly. They don't align it either, the nose cone does.

As for the pilot bushing, if it's a bronze bushing or even a steel one, I go to my can of old taps. I forget which size works, but running a tap into the hole that will dig into the bushing will eventually screw it out.
 

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If it helps, the clip is held on by a dome headed solid rivet. You can see the head in your pic. The clip is able to move around some from the attaching point. Totally feasible that misalignment somewhere else could move the clip a bit.
 

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You have a self-aligning TO bearing. Are you sure you don't have it rotated in the fork so that the fork is pushing on the self-alignment "hump" thus not allowing the TO to center in the fork?
I had the TO bearing positioned wrong. I had the clips on the outside instead of in the center. I am going to have some longer bolt heads cut off so I can screw them in and align the tranny onto them as I am doing this by myself. Trying to lift this tranny and get it in position is a ball buster, even with the Pittsburgh tranny jack I bought. The bolts will let me slide forward into position perfectly to get it on. Plus it will save my arms and pec muscles not to mention the ab workout I have been getting bending up and down at the waist. Hopefully the tranny Jack works a little better sliding it in than it did taking it out. I still had to roll the tranny onto my gut and roll it onto the floor. My neck can't take more of the wrenching it up to see either. Thanks for all the input guys. Now I need to buy some high temp bearing grease to lube the inside of the bearing. Looks like all the moving on and off wiped it all off.
 

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So I got the longer bolts to help mount the trans and cut the heads off. I got them screwed in and everything greased up and was getting ready to install the trans when I realized the TO bearing was off center and as hard as I tried I could not get it to slide farther on the fork. My neighbor came by and he checked it out and after doing some measuring of the bearing and the fork it looked like the the bearing diameter that slides onto the fork was 1.623 and the rough estimate while in the bellhousing the fork gap was 1.610. I measured my old forks and they were both 1.65+. So the fork is too narrow for the bearing to slide past the center diameter. I pulled off the bellhousing and took out the fork for a more accurate measurement and sure enough it was 1.610. That is .013 smaller than the diameter of the bearing. No wonder it wouldn't slide all the way on. I purchased the fork from GM Classics so I hope mine was a fluke. Some of you may be saying to just grind the ends of the fork down. Thought about that and Nope! I want a new one, not one modified to work. Besides the rivet holding the spring looks a little Mickey Mouse and could pop off with enough pressure. Thinking maybe to see if GM still has any in stock. So now I really think I will replace the pilot bearing since I am halfway there. I already have the bearing so I will just have to buy new bolts for the pressure plate and hopefully get a somewhat accurate torque while on the car. One step forward and two steps back. What a waste of a vacation week as far as the car goes. I was hoping to get the car off the ramps and moved to the side so I could park my driver in the garage. Oh well!
 

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The clutch fork is Nova only and I would guess was discontinued by GM 30 or 40 years ago. Original part number is 3788401 for reference. Are you sure you have the correct throw-out bearing? The 4-speed one is different than the 3-speed, but that should not matter with this issue. GM #907538 ND bearing number CT24K. Book shows GM changed the bearing in '68.

The retainer clip as far as I know was considered a serviceable item, I have seen replacements. I think that is part of the reason it was riveted, instead of welded on.
 

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There are at least two manufacturers of that clutch fork. As stated by SouthBay2s, the fork is for '62-'67 Chevy II, and other than NOS, there are only two routes. One is made in India, and I do not know where the other one is made. All I know is that I had the one made in India to install in my car as I didn't have a good original one, and it was so poorly stamped I found a decent original and used that.

If there's a silver lining, you found out about it now and not later, after some mechanical failure.
 

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Thanks all. It is definitely a poorly stamped fork. I do have an older one but do not see any stampings so not sure it is GM although it is real old and worked in the day. It has the broken spring clip on one side although is in good shape otherwise. GM Classics and a few others do make the spring clip and it comes with a rivet but I don't have a rivet gun. My body man would probably charge me $50 jus to mount it. I'll check with 4 speed conversions or figure something out.

Thanks.
 

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The GM Classics one in all likely hood is the Ted Williams, which would be made in Taiwan. This will be the fork virtually everyone else sells. The India one was probably an older Dorman or similar parts store replacement. A lot of driveline small parts were made there.

The site Alf posted may actually have an NOS one. They have a lot of good stuff, I am on that site frequently.

I can help you with a used one if you cannot track down NOS.
 

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The GM Classics one in all likely hood is the Ted Williams, which would be made in Taiwan. This will be the fork virtually everyone else sells. The India one was probably an older Dorman or similar parts store replacement. A lot of driveline small parts were made there.

The site Alf posted may actually have an NOS one. They have a lot of good stuff, I am on that site frequently.

I can help you with a used one if you cannot track down NOS.
I checked out the site and nada. I am going to see if I can take my other non 66 fork and remove the spring clip and put it on my broken GM Nova fork. Just gotta find a rivet. if not I'll look you up for a good used fork. Maybe I can get someone to buy my non 66 fork fork that is in great shape. I am getting tried of buying repop crap.

Thanks everyone for the input.
 

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So I got the new pivot ball stud in and yes it was a 1/4" longer. Made all the difference in the world. Now I have a new problem which I did not notice originally. The clutch forks clip is tack welded off center and when I put the throwout bearing on it does not ride in the clip properly. As I was looking I can see the clip has more space on one side than the other so bearing does not center on the clip and is barely holding on one side. Now it looks like I am going to have to take the bellhousing off and pull the fork and order a new one. Hopefully GM Classics will just do an exchange. I go back to work Monday from vacation and was hoping to have this out of the way. Now time will be limited as to when I can work on the car. Still a ton of work to do and the tranny and engine was just a drop in the bucket and those are still far from being completed.

Now that I am going to have to remove the bellhousing I guess I will pull the clutch and replace the pilot bearing. It is the original one and there were no issues but now that is is coming apart I may as well do it Any tips on removing? I have heard of bearing grease to squeeze it out but prefer using something less messy. Maybe pep boys will have some sort of tool. I replaced it in my old engine and think I borrowed a tool from them or somewhere.

Thanks
Michael
Here's where I removed my pilot bushing... post #150 and on . The slide hammer removal tool did not work for me... You will need to get the install tool anyway, so use it like I did to remove the bushing. You can use gease as well, but bread cleans the hole and removes the bushing
Another hint: bronze bushing doesn't need much if any grease. I put to much in the shaft hole and it actually made it difficult to install the tranny: the air couldn't escape.

My T/O bearing flopped around a lot, but once installed was fine I bought the upgraded ( stronger) clutch fork from classic industries.

Good luck!

 
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