Bent clutch fork?

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Bent clutch fork?

Postby mhuppertz » Fri Jun 22, 2018 7:27 pm

Is it possible to bend a shift fork? There is a ton of play in mine and it has a very short engagement, so I am having trouble with disengagement.
Either that or the pivot point is 2 inches too short, or maybe the pivot wore through the fork?
Anyone had experience with something like this?
MARK
'93 W250, HTT Stage IV/16cm, POD's, cut AFC pin, Pump advanced, Pyro, Boost, Fuel Pressure Gauges all non functional, burned wiring, 3/8” fuel line, BHAF on custom intake, 3,200 Spring, ARP Studs, New Head at 392K, Detroit Locker, NV4500, other stuff…
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Re: Bent clutch fork?

Postby PToombs » Sat Jun 23, 2018 6:23 pm

It's very possible to bend a fork, I've seen it before. Usually the shifter is too far 1 way and not enough the opposite way though. The fork can wear thru the plate it rides in too, then when you shift it goes way past in one direction and won't engage that gear. It's also possible that the set screw holding the fork to the rail is loose so the rail is sliding in the fork. 1st step is pull the shifter and make sure the shifter is correct in the rails and nothing is worn. The next step will be to pull the trans top and check it out inside.
pete

Just enough power to break everything behind the crankshaft.
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Re: Bent clutch fork?

Postby mhuppertz » Sat Jun 23, 2018 6:51 pm

Got under there with a flashlight and a helper, as soon as the clutch pedal is touched it begins to move the fork and throw out bearing. The crank does not move and the pivot is tight. So either something is wrong with the pressure plate or the pilot shaft bushing is galling?
MARK
'93 W250, HTT Stage IV/16cm, POD's, cut AFC pin, Pump advanced, Pyro, Boost, Fuel Pressure Gauges all non functional, burned wiring, 3/8” fuel line, BHAF on custom intake, 3,200 Spring, ARP Studs, New Head at 392K, Detroit Locker, NV4500, other stuff…
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mhuppertz
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Re: Bent clutch fork?

Postby mhuppertz » Sat Jun 23, 2018 8:23 pm

MARK
'93 W250, HTT Stage IV/16cm, POD's, cut AFC pin, Pump advanced, Pyro, Boost, Fuel Pressure Gauges all non functional, burned wiring, 3/8” fuel line, BHAF on custom intake, 3,200 Spring, ARP Studs, New Head at 392K, Detroit Locker, NV4500, other stuff…
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mhuppertz
14mm rotor
 
Posts: 577
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Location: Tijeras (Zuzax) NM
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Re: Bent clutch fork?

Postby mhuppertz » Sun Jun 24, 2018 7:04 am

I'm starting to the the pressure plate diaphragm fingers are probably weak or bent, so I am not getting full movement to release. the outer part of the diaphragm seems to be fine because the clutch never slips except under conditions that exceed its torque rating... This LUK Gold probably has more than 2k miles on it, so maybe I should just bite the bullet and replace it.
MARK
'93 W250, HTT Stage IV/16cm, POD's, cut AFC pin, Pump advanced, Pyro, Boost, Fuel Pressure Gauges all non functional, burned wiring, 3/8” fuel line, BHAF on custom intake, 3,200 Spring, ARP Studs, New Head at 392K, Detroit Locker, NV4500, other stuff…
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mhuppertz
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Re: Bent clutch fork?

Postby PToombs » Sun Jun 24, 2018 5:14 pm

Crap, my bad! I was thinking shift fork. :oops:
It looks like it's not throwing far enough to me. How is the bushing where the master cyl rod mounts on the clutch pedal arm? That pin wears and you can get almost a 1/4 inch of play there.
pete

Just enough power to break everything behind the crankshaft.
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Re: Bent clutch fork?

Postby mhuppertz » Sun Jun 24, 2018 5:32 pm

There is zero play in the linkage, in fact when I have my son just barely touch the pedal I see movement in the fork. It isn't that. I wonder if the pressure plate fingers can get weak and bend?
MARK
'93 W250, HTT Stage IV/16cm, POD's, cut AFC pin, Pump advanced, Pyro, Boost, Fuel Pressure Gauges all non functional, burned wiring, 3/8” fuel line, BHAF on custom intake, 3,200 Spring, ARP Studs, New Head at 392K, Detroit Locker, NV4500, other stuff…
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Re: Bent clutch fork?

Postby PToombs » Mon Jun 25, 2018 5:56 pm

It's possible, especially if the throw out bearing went bad once, if it seized up that would cause them to get hot and lose their temper.
pete

Just enough power to break everything behind the crankshaft.
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PToombs
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Re: Bent clutch fork?

Postby mhuppertz » Mon Jun 25, 2018 8:29 pm

PToombs wrote:It's possible, especially if the throw out bearing went bad once, if it seized up that would cause them to get hot and lose their temper.


Never lost the throwout bearing on this clutch, but I have (on occasion) put some heat into the clutch.

Making me crazy. It sucks pulling the tcase and tranny, friggin heavy!

Plus if I am going to all that trouble I might as well replace the clutch anyway, which ain't cheap for a good one.
MARK
'93 W250, HTT Stage IV/16cm, POD's, cut AFC pin, Pump advanced, Pyro, Boost, Fuel Pressure Gauges all non functional, burned wiring, 3/8” fuel line, BHAF on custom intake, 3,200 Spring, ARP Studs, New Head at 392K, Detroit Locker, NV4500, other stuff…
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mhuppertz
14mm rotor
 
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