hydraulic clutch not disengaging

[harleydodgeman]

i have a 64 plymouth fury, 440 4 speed that i am mocking up right now using a 3/4" wilwood m/c and a 7/8" bore wilwood slave. the engine is new and is not running yet, I am very new to 4 speed and clutch setup and need some questions answered. Is it possible to tell if the clutch is disengaging by just putting it in gear, pressing down the pedal, and having somone turn the rear yoke by hand? Should you be able to turn it by hand? or does there need to be some sort of load on everything to tell if the clutch is disengaging, (example wheels, rear end, drive shaft all hooked up) if you look up into the flywheel, clutch, and pressure plate assembly, should there by a noticeable gap between the clutch and pressure plate when it is disengaged? How much free play or distance between the throwout bearing and clutch fingers should there be to allow for wear before i press the clutch in? anyhelp would be great because when i press in the clutch, it looks like the clutch should be disengaged but i cant turn the yoke by hand. i just dont have any idea how much the throwout bearing needed to move to disengage the clutch. Please someone give me some ideas on this.
thanks

 

[Meep-Meep]

By the time you figure out all the ratios in a mechanical linkage and the distance the pressure plate moves away from the disc it's very little (maybe .050") compared to the pedal travel - and the hydraulic system has to duplicate that movement.

If you step on the clutch pedal you should be able to turn the disc without too much force. You don't want the throwout bearing to be riding on the fingers when the clutch is out but it should be pretty close so it's ready for action.

 

[Meep-Meep]

Oh yeah, somewhere there is an optimum ratio between the MC bore and slave bore, and do you know if what you have is correct for your application?

 

[harleydodgeman]

yes i have a 3/4 m/c and 7/8 slave both by wilwood and recommended to be used together. I got the clutch to fully release last nite. i believe that i have the wrong clutch arm and pivot for the car and the arm was not seating against the throwout bearing correctly. now when i push the clutch in, i can turn the disk by hand. I guess my main question now that it's releasing is if anyone out there that has a 4 speed car, can turn the yoke by hand when the clutch is pushed in. Right now my clutch disc turns freely by hand, but the yoke turns a little harder. but it turns. is this due to all of the geas spinning inside and creating drag on the yoke? also what is typical distance that you guys set your t/o bearing from the fingers at when you are adjusting your clutch with mechanical linkage. Just trying to allow for enough wear but not to much distance.

 

[Meep-Meep]

If you have the tranny in first gear it will be difficult to use the yoke to turn the input shaft. Put it in direct - fourth gear - and it should be easier. You are still fighting the gear train and oil so I wouldn't expect it to spin right up by hand. The clutch adjustment spec in my 68 book gives 5/32" free play at the end of the release fork to produce the desired 1" of pedal free play.

 

[Revhendo]

If I remember correctly, there is a feeler gauge measurement for the clutch disc to pressure plate with the clutch pedal depressed. I don't think it was more that about .010, but that's been a long time and my crusty brain ain't what it used to be.