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MGB Clutch won't disengage

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Apache

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How much travel should you have with slave cylinder rod when disengaging clutch. Am only getting about 3/8" and clutch won't disengage. System new and bled at slave cylinder, with no bubbles.
 
With a second helper in the car, have them pump the pedal a few times and hold it down. If the observed "throw" of the slave cylinder increases on each stroke you still have air in the system. Another thought is that the bleed screw and the input hose are in the wrong positions; the bleeder should be at the top.

How long had the car sat between working and now? Sometimes the driven plate will stick to the flywheel due to rust.
 
Check the freeplay at the pedal with your hand to see how much travel before you feel the slave cylinder move. Sometimes it takes awhile for the m/c piston to return all the way to the beginning of its travel , thus giving you a fuller stroke. Tapping on the side of the m/c with a hard plastic hammer will help return the piston if that's the case. Sometimes they will start working properly by rapidly pumping the pedal through the full stroke.
 
Be careful of "rapid pumping"....more than three and you can overextend the slave piston. Two or three times to test should do it.
 
Rapid pumping will airate the fluid and cause the piston non return. Slow strokes are best. If the disc is stuck, place car in third gear and rock or find a hill and let her go.
 
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