1989 F250 4x4. 5.0 with M5od transmission. I just replaced the clutch disc, pressure plate, pilot bearing, throw out bearing and concentric slave cylinder. All the parts are oem spec from Rockauto. I had the flywheel ground by a local machine shop. I made sure I kept everything clean and free of grease and dirt during reassembly-I did get a little brake fluid on the flywheel, but I cleaned it off with brake cleaner and a rag.

I got it all back together, bled out the slave and master and had a good pedal. When I took it out for a short test drive the clutch is slipping bad at anything over 1800 rpms. After I got it back in the garage I pulled the inspection cover to check the slave cylinder release distance and it was slightly less than 1/2" (Haynes manual says anything over .425" is good). Looking further at the slave I noticed there was grease on the slave side of the throw out bearing, but not on the face of the throw out bearing-I'm assuming this is normal grease to lubricate the throw out bearing.

I read back through the Haynes manual and it said the clutch may take 30-40 normal starts to seat properly. So I backed it out and did normal starts in 1st and reverse in my driveway to seat the clutch. As I was doing this I suddenly had a rock hard pedal that would not move at all. The lne from the master cylinder had popped out of the slave cylinder at the quick disconnect. I cannot get it back in l and I'm thinking of opening the bleeder on the slave to try to push it back in.

Ok, so the issues:
New clutch is slipping even with all new parts. Any ideas on what to look at other than tearing it all apart and starting over? Or did brake cleaner leave enough residue to make it slip??

Is a little grease on the slave side of the throw out bearing normal?

Line came out of the disconnect at the slave cylinder.

Any help is appreciated.

 

The brake cleaner shouldn't be an issue.........You didn't say if you replaced the master cylinder. Could be an issue with it holding residual pressure. Where the line popped off the slave, and you cant get it back on, it makes me think it may be trapping residual pressure in the line........

 

Thank you for your reply. I did not replace the master, I was thinking when the line popped off and I couldn't even budge the pedal that meant the master was fine because there was no leak down.

Any other way to test the master?

 

I just did the clutch in my truck, from experience, make sure your pressure plate bolts are tightened down enough, you can access them through the inspection hole, no tear down necessary. They say 20 lbs but it's more... 20lbs left a gap between the pressure plate and flywheel for me...

 

i feel like i am missing something here . with the fluid line disconnected from the slave, do you STILL have a rock solid pedal, or is it sinking easily to the floor as one might expect ?
no worries regarding the brake cleaner, it isn't going to leave any residue.

 

wait.... if its disconnected the pedal shouldn't budge at all right? Because it's a quick dissconect it has a valve in it to prevent leakage when dissconected. With the valve closed there is no where for the fluid to go...

 

that's what i am missing then. thanks for the info !

 

I torqued them to 20. Do you think that could be part of my problem?

 

Yes, with the line disconnected the pedal doesn't move at all.

 

I want to say yes because that happened to me, can you tell if there is any bit of a gap between your pressure plate and flywheel?

 

no problem, I had to think about that for a minute

 

[QUOTE=BTFordGuy302;16852799]I want to say yes because that happened to me, can you tell if there is any bit of a gap between your pressure plate and flywheel?[/QUOTE

I can see one bolt through the access hole and it doesn't look like there is a gap. Just in case, I will torque them all to 29-which is the highest spec. I will also mark them as I go to make sure I get them all. Win or lose I'll post the results.

 

[QUOTE=Paul M.;16852846]yeah give that a try! Good luck hopefully that does it!

 

The minimal change of torque on the pressure plate is not going to do much at all.

Something is amiss. One of two things:
1) Your new clutch disc is too thin(not likley)
2) Your throw out bearing is riding the clutch.

My first thought is trying to determine if the throw out bearing assembly is staying extended too far and pushing on the clutch.

Try this: while carefully watching the bearing, open the bleeder screw on the slave and see if it retracts. If it does, then for some reason the fluid is not being able to return to the master when pedal is released.

 

Thank you for the advice.

The slave is retracting all the way-that was one of my first thoughts so I did what you said and I also tried to push it back with a screwdriver (gently).
My next concern is that the flywheel is too thing after being ground and the disc springs are resting on the flywheel bolts and holding the disc slightly off the flywheel.
I haven't had a chance to torque the pressure plate down a little more-I plan on getting to it tonight.