is this normal?? mech clutch

[big83chevy4x4]

working on my buddies 81 k20, has 465/208. we droped his motor in it (pain in the ASS) and hooked it all up, i adjusted the clutch best i could figure, and while he was pushing the clutch the cab was moving. it really moves when the pressure plate bottoms out.

check the cab mounts, all good. the only thing i can think of is the fenders arn't on so it alows it to move. /forums/images/graemlins/dunno.gif

also what is freeplay spec and where do i measure at?

 

[84_Chevy_K10]

I believe the free play spec is somewhere around a 1/4" but I have never looked at the book for that. It is measured at the clutch pedal itself.

If the cab is moving it's not secured correctly.

No that is not normal.

 

[big83chevy4x4]

ok thanks,

i guess we will see if it moves when we get the front clip back on. the cab isn't rusty around the mounts and the mounts are good. but also there are no doors on it or a windshield in it.

 

[nvrenuf]

What part of the cab is moving? Literally the whole corner?

I have seen my own K10's firewall flex after the installation of a really strong pressure plate. When this happened the whole cab didn't move rather the area of the firewall area the master cylinder could be seen "breathing" when the clutch pedal was cycled.

 

[big83chevy4x4]

when we noticed it, the left fender was on and the right was off, the right side of the whole cab moved up and back. it moved about 3/4". also as i was laying under neath the truck, i could watch the floor move backward 1/8" on the driveside, but it could have been twisting the cab because the pass side was moving