|The MGA With An Attitude
TESTING CLUTCH ACTION IN THE CAR - CT-101
At 05:16 PM 10/10/03 -0500, Richard Koseluk wrote:
>"I carefully read and followed your advice on the spigot bushing. Although I believe I have the clearance correct. Is there any way to test it for sticking prior to hooking everything backup? Engine is back in of course."
Sure. Jack the car up and put it on stands so you can get underneath and the rear wheels don't touch the floor. Leave the hand brake off and put it in 4th gear. Use a big Crescent (adjustable) wrench to grab the clutch release lever and pull it back 1/2 inch at the slave cylinder pushrod. If you can then turn the
propshaft by hand, the clutch is working perfectly, and the spigot bushing is not binding. For the purpose of testing clutch release, any gear will work. (The idea is to engage some gear so that when you turn the propshaft the input shaft and clutch disc will turn, thereby verifying that the clutch is actually released).
While you're under there, also check the hydraulic action. Have a helper press the clutch pedal all that way to the floor. At full stroke the slave cylinder pushrod and clutch release lever should move at least 1/2 inch (usually about 5/8 inch). If it does not move that far, you probably have air in the hydraulic line, and it needs bleeding. If you're sure all the air is out, and it moves about 1/4 inch less than expected, then you may have an incorrect 3/4" bore master cylinder rather than the proper 7/8" bore unit. You can check that by removing the master cylinder pushrods and the end plate to measure the bores.
The clutch pedal should rise, and clutch re-engage, as fast as you can lift your foot from the pedal. The metal lines for the clutch circuit are larger bore than the metal lines for the brakes, specifically to allow this quick return of the clutch. The pedal should rise fast enough stay in contact with your foot until it hits top of stroke. If you can pull your foot up faster than the pedal will rise, you have a clogged clutch hose (or maybe a much less likely kink in the steel line).