93 Jeep Cherokee clutch master cylinder

I replaced the original clutch master cylinder and the clutch cylinder at about 200,000 miles. I replaced the original master clutch cylinder that was made of metal with a plastic one. This one did not last long, one day I was stopped at a traffic light, pressed the clutch down to put in gear and heard a “pop”. That was the end of that one. The clutch would not disengage. Had to drive the Jeep home by shifting without the clutch and used the starter to take off from a stop. My mechanic then replaced the clutch master with a new metal one. This one is now starting to give me problems. It is not that old, only had it for about 30,000 miles. The clutch works fine on short trips, shifts into gear smoothly and operates perfectly when it is cold. When I go on a longer trip, the clutch grabs closer and closer to the floor. So much so that it is hard to shift because it is not disengaging fully. Also when stopped it is hard to get into gear because it is not disengaging. I have to pump the clutch pedal to get it into gear.

I checked the clutch fluid reservoir and it is full, it is not leaking any fluid, which indicates it is not the clutch cylinder but must be the clutch master cylinder. Fluid must be getting by the piston when it becomes warm. Could there be another reason which would cause this problem? Could this be caused by air in the line? Should I bleed the line before getting a new clutch master? If I replace the clutch master, which kind should I get, who makes the best one? I would hate to have the same problem again with another one after going through the trouble of replacing it. Is this a common problem with Jeep Cherokees that have manual transmissions? This Jeep has always been rough to shift when on a long trip. I can always remember the clutch grabbing closer to the floor when on a long trip. Any advice would be appreciated. I love this website, you guys have been a tremendous help to me in the past with other problems I have had.

I had to replace the one on my 85 two times in 3 yrs .On my 92 getting ready for the third I am thinking its starting to go bad I have had it for 4 yrs so it seems like about every yr I have to replace it . its a DD I use cluch fulid instead of brake fluid that seems to help and flush it about every 6 mo or when ever the fluid get dark color.on the 85 had one plastic and on my 92 have used one plastic MC .And had to replace the fuze box on the 85 it melted complet apart.I have watch the one on my 92 real close if I see any leaks at all I pull the carpet back and spray it down with brake cleanerand blow it out with an air hose. If yours has leaked that much better check your fuze box and get it cleaned before you have to replace it its ajob you dont want to do I know its a bitch the whole dash has to come apart almost to the fire wall.

Fortunately mine has not leaked out. I am not losing any clutch fluid at all. What appears to be happening is that the fuid is going past the piston and not moving the clutch cylinder completely to disengage the clutch fully. I do not know why these clutch masters do not last long. I think I am going to have to buy a new one because the only thing it could be is a bad clutch master. Who makes the best one? Should I just go to the Jeep dealer and buy a genuine Mopar part? Are there any after market ones that are better? I am getting tired of replacing them.

you may try flushing it .Pull all the fulid out spray with brake cleaner wipe it out good. add new cluch fluid and have some one crack the bleader while you pump it slowly .go thru a fu cyl of fulid . and try that .I have seen a did diffance in mine by doing this I do the same thing with my brakes once a yr .Brake fluid has a bad thing about asorbeing water from the air . there is a lot of heat under the hood of a jeep. That may be one of the ploblems with fulid and MC .I know on brake systems most people never flush their brakes this is the reason MC and wheel Cyl go bad . The iron one rust and Aulm one croued from water in the brakes fluid. If you think about it how dose wheel cyls rust . Its because water is asobed from the air and get taken thru the lines to whole system and when it get hot the water seperates from the brake fluid. How do I know when I had my shop I went thru Napa and Car Quest training and got a cert from them on anti lock & standard brake systems.

Thanks for the advice dobbs, I never thought about changing the fluid. I guess its one of those things that no one ever thinks about and gets neglected. Where is the bleeder valve located? I never bled the fluid before, I had a mechanic replace the clutch master last time. Also, shouldn't it be leaking fluid from the back of the piston somewhere? I have to take another look at it. But like I mentioned before, the reservoir is full. When the Jeep is cold, the clutch works perfectly. I will have the fluid changed and bled real good before I do anything major.

It should have an internal slave cyl its on the drivers side you will see aline going in and one comming out with a bleader on it .Thats the one you want. let me know if it helps your fluid will plobley be verry dark when you blead it just keep going till it clear. If you do your brakes do them the same way it makes a big diff in them.I think if you look in your factory service manual it say to do it at 75,000 or so would have to look at mine but it dose say to fuush the brake system and the cluch system. A long with a lot of other systems. Like I said most people never think about it .

Thanks for your advice dobbs. I got the ambition to bleed the clutch cylinder line on Sunday. It was a pretty messy job but I got it done. Had someone step on the clutch pedal and I opened the bleeder line. I did this several times and filled the reservoir with new fluid each time. I pretty much replaced all the old fluid with new fluid. I believe there was quite a bit of air in the line. I felt a major difference right after I did it. I have done a good amount of driving since I did this and it is so much better. Goes into gear very smooth and shifts so much better. I also used fluid that is specifically clutch fluid like you recommended. I used the clutch fluid made by Gunk. Thanks for your help, it is very much appreciated. I love this website, it has been such a great help to me.

Like I said it helps alot the same with brakes so much diffance once they are flushed out . I dont know what the diffance in cluch and brake fulid is but there is a diffance in the way it performs. let every one has it dose glad to be of help