Hydraulic clutches

Ok so me and my lil brother got volunteered to put a clutch in a 1991 gmc 1 ton which wasnt bad but it turns out i don’t know as much about hydraulic clutches as i thought i did so i need some help. What is the trick to bleeding them so that i can get it to work or did we do something wrong?

The concept is pretty much the same as bleeding brakes, but if the clutch components aren’t assembled right it won’t work. What have you done so far? Have you been able to get fluid to come out of the bleeder on the slave cylinder?

You didn’t do anything wrong. Hydraulic clutches are harder to bleed compared to bleeding brakes. On a hydraulic clutch, the slave cylinder has a piston the same size as the master cylinder. So it takes longer to transfer all the fluid to get the air out. On a brake system, the caliper pistons are much larger than the master cylinder piston. So it takes no time to remove the air out of the system. Just keep bleeding the clutch hydraulics, and you’ll get the clutch to work again.


we probably put something together wrong i don’t know i’m just going to give up trying to fix anything i guess.

ok so heres the deal took the clutch back apart nothing wrong,replaced the slave cylinder,bled the system absolutely no air at all and the slave cylinder extends as far as it can any other ideas on what could be the problem? Or is it just another case of someone attempting to fix something they shouldn’t have?

Did you replace just the clutch plate or also the throw-out, pressure plate and pilot bearing?

What happens when you have the engine running and you try to put it in gear? I know you say it doesnt work but give more info.One common mistake is putting the disc in backwards.Is it marked “flywheel side”?

replaced everything, and when the engine is running and u push the clutch it just grinds when u try to put it in gear and i’m pretty sure we put the disk in right but maybe we didn’t.

Bleed the clutch some more. There is still some air in it. We just did a clutch, and the slave cylinder had to be disconnected to remove the transmission. We went through a bottle and a half of brake fluid to get the clutch bled enough to drive it.

ok so the latest in the saga i was wondering when we went to get the slave cylinder for this pickup they had like 4 different ones to pick from does that mean we might have got the wrong clutch cause we didn’t know any better? They said that this particular year was when they changed the body style so that is why there are so many slave cylinders so thats why i was wondering if maybe we got the wrong clutch. Just for the record we were not the ones who purchased the clutch the guy that got it might not have known any better i don’t know.

ok so the clutch problems are over yesterday i took it all apart again and put it back together and it just decided to work its just another great mystery of the world i guess. Thanks for all the help.