Wonky clutch release fork?

gearheadbill

Senior Member
Im working on a 34 pickup with 53 Mercury engine/5 speed installation. When I first got the truck I drove it less than 1/2 mile before pulling it into the shop to work on it. When I bought it I knew one of it's many problems was that the clutch acted as though it was not releasing...figuring that it was a linkage geometry adjustment problem which would be addressed it due time. Fast forward several months. New steering, front suspension replaced, distributor/carb issues resolved and a million smaller things fixed. With the truck running very good and while the front sheetmetal was still off, I think I'd like to run her around a little; see how it all works. No dice!

After fussing with adjusting this and that etc. the clutch still seemed to not release. Grind, grind, grind. Finally I unhooked all the linkage to the release arm on the cross shaft and clamped the arm/TO bearing as far forward as it would go. Grind, grind, grind. Absolutely no difference. Pulled the engine/trans out over the weekend as I'm not very good at working lying on my back anymore. It's now out and all apart so I can see how everything works/doesn't work together.

Long story, yet to be resolved, but I think maybe the crudely homemade pilot bushing has the input shaft in a bind ...at least that's where I'm headed first. The pilot hole is at least .030 larger than it should be and one side is obviously worn like the clutch disc/input shaft/pilot bushing aren't installed so that they're all on the same centerline. Maybe binding up.

Please take a look at the TO bearing release fork in the pic. While maybe not directly relating to the issue I described above, I'm concerned because it's vertical 'fingers' are both bent away, which allows a lot of side to side movement on the TO bearing. This of course allows the cross shaft to move side to side...all looks wonky to me. Nothing like an original Ford fork that I have.

I am replacing the transmissions front bearing cover as well because the area of the snout that the TO bearing rides is very worn and funky too. These are the type of things that happen when you buy someone else junk and try to fix it. Keeps me out of the bars I guess.
 

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I thought there should be about 3/8 to 1/2 cut off the input shaft at the point where it goes into the Pilot bushing. Didn't you say the input shaft bearing was bad. I wonder what would cause all that wobbling around and all that wear ??
 
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I thought the Input shaft, the part that goes into the pilot bearing/bushing should be shortened about 3/8" to 1/2". I see you need to replace the input bearing and there is grinding also wear on the part of the input bearing retainer where the T/O bearing rides. Do you think all that could be caused by the input shaft being too long and getting WONKIE . That is a technical term . JMHO
 
If your original fork fits the TO bearing swap it and throw the other away.
You should be able to measure from the bolting surface of the transmission to the end of the input shaft, and be able to compare that distance from the bell housing surface to the inside of the pilot bearing max length and know if is too long.
Good luck.
 
I thought the Input shaft, the part that goes into the pilot bearing/bushing should be shortened about 3/8" to 1/2". I see you need to replace the input bearing and there is grinding also wear on the part of the input bearing retainer where the T/O bearing rides. Do you think all that could be caused by the input shaft being too long and getting WONKIE . That is a technical term . JMHO
I would think so but/if only....the trans input shaft is approx. 7" in length and the depth of all the combined parts and pieces measures 8+". It should fit. But what do I know really. The cavity in the back of the crank is deep.
 

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If your original fork fits the TO bearing swap it and throw the other away.
You should be able to measure from the bolting surface of the transmission to the end of the input shaft, and be able to compare that distance from the bell housing surface to the inside of the pilot bearing max length and know if is too long.
Good luck.
I was actually able to cold press the fork into shape. It is a forging. Now fits the TO bearing really nicely. Thanks Mike.
 
I appreciate all the replies so far. Thanks.

On to another question. The 2 pics here show the amount of front to back travel that the arm moves from first contact with the TO bearing until the TO bearing has fully depressed the PPlate. Not a lot of travel but enough? Seem right?
 

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guess you have to look at the fork to plate. Arm has length for leverage. The arm might move an inch the fork may move more or less. Seems a bit restrictive to adjust any kind of clutch pedal linkage. just a thought.


is the wobble more to do with the the throwout carrier and the shaft? or plate arms? dont know.
 
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That doesn't look like much travel. Maybe enough if the TO bearing was already touching the PP arms. If it were me, I would modify the arm so that when the slack was out of the travel to the PP, I would want the arm to be farther back toward the pedals. Maybe drill another pin hole to hold it on the shaft clocked a bit clockwise. Maybe you are not getting enough travel to completely disengage the clutch.
 
Make sure the clutch equalizer shaft does have a crack in it. Mine did and took awhile to find it. Also check the pin in the clutch fork
 
I agree that it doesn't look like much travel on the release arm. At one time there were some clutch discs that were too thick for the pressure plate to release. You might want to eliminate that possibility.
 
I agree that it doesn't look like much travel on the release arm. At one time there were some clutch discs that were too thick for the pressure plate to release. You might want to eliminate that possibility.
While I'm not familiar with the exact specs of the 5 speed conversion used in my truck, I believe the clutch disc itself to be S-10/Astro van; not Ford and certainly not early Ford. The 1"-14 spline input shaft pretty much requires this or similar.
 
That doesn't look like much travel. Maybe enough if the TO bearing was already touching the PP arms. If it were me, I would modify the arm so that when the slack was out of the travel to the PP, I would want the arm to be farther back toward the pedals. Maybe drill another pin hole to hold it on the shaft clocked a bit clockwise. Maybe you are not getting enough travel to completely disengage the clutch.
One of the things I will do is cut and re-weld the arm, moving the clevis cross hole further toward the 2 o'clock position when released. But in the pics the first one shows the at rest but fully up against the TO bearing and PPlate fingers position. Pic 2 shows where it should be (relative to position in pic 1) when the PPlate fingers are fully compressed and releasing the clutch plate. So theoretically I should have all the movement I need as is. ???
 
I was actually able to cold press the fork into shape. It is a forging. Now fits the TO bearing really nicely. Thanks Mike.

Be sure the tips of the fork are in alignment so that both contact the throw out hub contact surfaces at the same time. If not you get a bit of clutch chatter.
 
I just completed the exact same conversion you have. With the flathead engine is in the engine stand i was able to determine a number of issues caused by the type of bell-housing conversion you have. First I machined the bronze pilot bushing to locate into the rear crankshaft hole. After i determined the bell housing located correctly on the crank center line. Note it was off center so i had to correct that issue. I was then able to install the T-5. Test fitting everything I discovered the input shaft length was bottoming out into the crankshaft I was barely able to turn the output shaft of the transmission. After removing 1/4 inch from the transmission pilot I was now able to turn the output shaft easily. Next issue is theres no provision for the return spring used on the Ford release hub assembly. Without the return spring the release bearing is always touching the pressure plate fingers. I see in the pictures the return spring is used if the bracket design is not centered correctly that will cause sideways issues. I made the return spring location identical to how its located in the Ford flathead transmission case so it pulls straight and on center. Seeing how little release you have like others mention thats not enough. Later model pressure plates non flathead ford type have fingers that are longer than the Ford flathead pressure plate these latter model pressure plates with longer fingers will bottom out on the release bearing hub assembly when that happens your unable to get a full release of the pressure plate. This is long winded but hopefully you can use some of this to solve your problem.
Ronnieroadster
 
Ronnie Roadster is right although I designed my kit for the pilot bushing to go into the flywheel which centers the bushing correctly. In my instructions I address the length problem in some cranks without a deep relief. I'm assuming the truck had a B&B Pressure Plate because the Merc flywheel was drilled for it. I've been selling the kit for almost 25 years and have never recommended a B&B pp but have recommended a Long 3 finger PP. I send all my kit customers to Fort Wayne Clutch and recommend the Long PP without the counter weights. Talk to Leo. I've always been available for help with my kits. Gary at Cornhusker
 
I just completed the exact same conversion you have. With the flathead engine is in the engine stand i was able to determine a number of issues caused by the type of bell-housing conversion you have. First I machined the bronze pilot bushing to locate into the rear crankshaft hole. After i determined the bell housing located correctly on the crank center line. Note it was off center so i had to correct that issue. I was then able to install the T-5. Test fitting everything I discovered the input shaft length was bottoming out into the crankshaft I was barely able to turn the output shaft of the transmission. After removing 1/4 inch from the transmission pilot I was now able to turn the output shaft easily. Next issue is theres no provision for the return spring used on the Ford release hub assembly. Without the return spring the release bearing is always touching the pressure plate fingers. I see in the pictures the return spring is used if the bracket design is not centered correctly that will cause sideways issues. I made the return spring location identical to how its located in the Ford flathead transmission case so it pulls straight and on center. Seeing how little release you have like others mention thats not enough. Later model pressure plates non flathead ford type have fingers that are longer than the Ford flathead pressure plate these latter model pressure plates with longer fingers will bottom out on the release bearing hub assembly when that happens your unable to get a full release of the pressure plate. This is long winded but hopefully you can use some of this to solve your problem.
Ronnieroadster
Thank you. Good information
 
FWIW: For the return spring anchor I drilled and tapped for a bolt inline with the throwout bearing carrier and parallel with the shaft. Drilled a small hole for the end of the spring and bolted it in with some locktight. Just cut of the hex head and your good to go.
 

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