need help with 91 clutch

hey guys i bought a 91 xj laredo. the clutch is very soft. im having to pump the clutch the same way youd pump brakes to get pressure. after you pump the clutch it catches the gear fine, without the pumping it wont go in. it also grinds when it goes in reverse. what do you all think is the problem? The clutch pedal goes almost all the way down before it gets pressure, that is before you pump it.

have you checked the fluid? It may need to be bled....

i tried bleeding it the same way youd bleed a brake. with the engine off pump it then open the bleeder screw. close it and make sure the level is good right? thats what im doing right now but the clutch is still soft. a friend suggested that it could be the slave cylinder. these are internal slave cylinders right?

1991 xj 4.0 ax15 np231

Could be the master or the slave. Is the slave leaking? Will usually be evidenced by fluid dripping from bottom of bellhousing. Typically the slave will leak showing it's bad. Also look under the dash at your fuse block. Is it wet with fluid? The master cylinders have a very nasty habit of leaking inside the truck all over the fuse block and under the carpet where it's hard to see. If so, when you replace the master, also clean the fuse block and fuses really well. Good luck.

i looked and theres no leaks under the bellhousing. ill have a look at the brake master cylinder, right? i have real good braking power, brake pedal is firm. the clutch fluid level is fine. brake master cylinder is fine too.

That's clutch master cylinder you need to check, not the brake.

sorry, this is very first standard vehicle i've owned and worked on.

yep, it is in fact leaking in the inside where the clutch pedal assembly meets the firewall. it's a very light leak right now. it looks like i'm going to have to replace the clutch master cylinder. anybody know of a good detailed write up for this? this is the very first time i do this job. thank you all for the helpful info.

Bump....

I'm not trying to be a dick, i'm just at wits end.
I've been looking up and down for a write up, do
any of you all know where I can find one? Is it as simple
as undoing the clutch pedal linkages and unbolting it
from the firewall?

jeepintexas said:

Bump....

I'm not trying to be a dick, i'm just at wits end.
I've been looking up and down for a write up, do
any of you all know where I can find one? Is it as simple
as undoing the clutch pedal linkages and unbolting it
from the firewall?

Click to expand...

i understand your frustration, but give people time to answer and realize its just a forum, you still need to have the skills to do the work. if you have basic auto/mechanical skills, this is not a hard job.

its really that easy although its hard to get to the 2 bolts holding it to the fire wall. also, dont twist the fluid line when disconnecting it from the master. the line is held on with a fitting just like a brake line and sometimes when turning the fitting, the line will twist with it.

what condition is the fluid in? is it black or is there a black ring in the master cyclinder?

if its the original master and slave, they should both be replaced.

if you just replace the master, just know that the slave is just a old as the old master and its getting fluid pressure from a new master.

to replace the internal slave, the trans must be pulled away from the engine about 10" to get acces to the slave.

thanks. im going to go ahead and replace the clutch mas cyl and see if it works. if it does ill replace the int slave cyl when i get a chance.

the fluid is dark i guess you could say dark grey-black. i dont see any type of ring though

thanks. im going to go ahead and replace the clutch mas cyl and see if it works. if it does ill replace the int slave cyl when i get a chance.

the fluid is dark i guess you could say dark grey-black. i dont see any type of ring though

I agree with doing just the master to start. I had an external slave with my '85 so can't really compare to the lifespan of the internal slave, but I typically went through about two masters for each slave through the 23 years I owned it.

Replacing the master is essentially as you and 89xj have described it. It sounds like you understand the bleeding process but hopefully someone will chime in if there are any tricks. The good news is that I think the bleeding process is a lot easier than it was on the old models with the external slaves (although i don't know that for sure).

Also, take IGOCOMMANDO's advice to heart if the fluid actually got onto the fuse block . The sooner you can thoroughly clean the block and each fuse and circuit breaker, the better your chances of avoiding problems that can last a long time. Don't ask me how I know!

Get back if any problems.

It's not a very difficult job replacing the master. I don't remember which style line the '91 has from the master to the slave. My 87 had a flare nut like a brake wheel cylinder and my '92 has a line that uses a roll pin and o-rings to attach to the master. The hardest part is getting the 2 bolts off and on. If you've got someone that can help with that, It goes much easier. What makes bleeding the system easier is fill the master cylinder with fluid and crack the slave cylinder bleed screw open to just a slow drip. Don't let the master cylinder go dry while doing this. let gravity do it's thing to push most of the air out. let it drip till the old dirty fluid has been pushed out. Then, bleed the system per the directions. Be sure to bench bleed the master per the instructions before installing on the rig. Good luck.

Thank you all for the helpful words. I got the CMC replaced and everything is working great. I'm going to explain the process to help other people like me who are doing this for the first time. I didn't do a great job of bench bleeding so I pumped it a bunch of times, like I read in another post.
This isn't intended as a write up, just a list of the steps that I remember that will hopefully help someone out.

1. Unplug and remove the washer fluid res.
2. Unbolt the old clutch master cylinder - one nut is on the engine side, other is inside
3. Remove the pin holding the clutch pedal assembly/linkage
4. Turn the clutch master cyl. to the side, be careful with the line - get a punch and a hammer and tap out the old roll pin
5. Pull the line out, and replace the o-ring
6. Bench bleed the new clutch master cyl. if you can
7. Install the line, and install reinstall the roll pin
8. Bolt it onto the firewall, reinstall the linkage onto the clutch pedal assembly - reinstall the little pin you took off.
9. Then just bleed it, if you weren't able to bench bleed it I found that pumping the clutch a tremendous amount of times made it firmer, I was then able to bleed it.
10. Hopefully this helps someone out.

So, you have good pedal pressure now? Engages the clutch like it should? Glad to hear you took it on and did it yourself.

Looks like I got here late. You really should snatch up a Chilton's manual or a FSM to help out when you are having problems. Also you should check out the Red River Chapter since apparently you are located in Texas!

IGOCOMMANDO, yeah i am getting good pressure. The clutch is shifting really smooth.
x2elite, yep i'm from south texas. I have a fsm for my renix, but i wasnt able to find one for my early h.o. I've been using the boards since 05, i just wanted to start using this name because i got a vanity plate that reads jpntx on my 87. I had a 06 LJ for the past 2 years, but i've since gotten married. I could no longer afford it. I usually just dive into stuff but this is my first standard and my first non-renix. i've had nothing but renix. I'm glad there is still guys around here giving kind advice. I'm glad to be back.