Flywheel hotspots = creaking clutch pedal?

[Mkultramega]

Hey everyone. I've been searching like a mad man but haven't found an answer.

When the flywheel is cold, my 94 ex M5OD takes off fine in first gear. If the flywheel heats up it starts to chatter taking off in first so I have to up the RPMs to get it to quit. Once the flywheel gets hot, the clutch pedal starts creaking like metal rubbing on rubber and the pedal won't come all the way back up. I have to shift, then lift the pedal from underneath with my foot.

For the life of me, I cannot see where the clutch pedal is rubbing or why...

Thoughts?

M

 

[Anime]

It's probably the clutch master cylinder either going bad, or just being low on brake fluid.

Check the clutch fluid reservoir under the hood, and add some DOT3/DOT4 brake fluid if needed. Keep in mind the rubber plug in the reservoir is made to fill the space so you don't need to fill the reservoir past the fill line.

You may also need to bleed the clutch to restore normal performance.

If this still doesn't fix the issue, or if the clutch pedal continues to squeak and the fluid reservoir gets low on fluid again, the seals in the clutch master cylinder are probably shot. It happens. Get a new Ford/Motorcraft master cylinder and replace it.

Note that the slave cylinders are also a problem point on these transmissions, so it's also possible the slave cylinder is bad, or is contributing to whatever the issue is. It could even be that the slave cylinder is what's leaking and the master cylinder is just creaking because it's low on fluid. You can pull the inspection plug on the driver's side of the transmission from under the vehicle, and shine a flashlight in there to see if any fluid is leaking on the bottom of the transmission. If brake fluid is all over the place in there, the slave has gone bad and needs to be replaced. Only way to do it is removing the transmission. Again, get a Ford/Motorcraft slave cylinder to replace it with to save the headache of having to do the next replacement any sooner than necessary.

 

[Mkultramega]

Thanks Anime! I checked the resevoir and is been full for months. No leaks tha I can find and the diapragm in the resevoir cap is fully retracted. I don't see any signs of leaks at this point and the truck shifts fine in all gears.

I'm happy to replace the MC ifyou think it will help. From what I gather, the clutch was replaced about a year ago (before I bought the EX) but the flywheel and MC have never been touched.

Thanks again!

M

 

[Anime]

The flywheels can get old and even wind up wearing out and getting hairline cracks all over, but this isn't too common. Something like this might be the issue if the problem really is the connection between the clutch plate and the flywheel. Good quality new flywheels from LuK are inexpensive, but like the slave cylinder, are a hassle to change since the transmission must be dropped.

The clutch pedal not coming back up might just be wear and tear from age, especially if it is the original. Could just be the shaft rubbing and getting hung up on the seals. I'd say get down close to it with a flashlight and inspect it from the footwell to see if there is even the slightest amount of brake fluid there, and then look at the housing from the engine compartment side to see if there are any cracks. You may need to have someone depress the clutch pedal while you're inspecting it to notice if any cracks show up when pressure is applied.

You should also inspect the clutch fluid line from the master cylinder to the transmission, just to be sure there is not major rust on either end, or any bulges or damage on the rubber hose

If the master cylinder creaks, and the pedal won't come back up, but pulling it back up with your foot works, and you can push it back again with pressure, I'd say that's the master cylinder sticking. At this point that would be the easiest possible fix, and if it does nothing, then you can be pretty sure the problem is something with the flywheel/clutch/slave inside the transmission.

 

[RangerX]

Here's a few thoughts I have:
The chattering flywheel may be from glazing on the surface. If you or the previous owner rode the clutch a lot, it could be glazed from that. Maybe it's just that they did not resurface the flywheel when the clutch was replaced.
The creaky pedal may or may not be related to the rest of the problems. I had a creak for a long time in my Ranger's clutch pedal, but did not have your other problems. We also have a Cherokee that has the same creak. I think it's just the bushing that the pedal pivots on.
Speaking of pivot, stick your head down by the pedal, and with a light, look way up at the pivot point. Look for cracks in the bracket, or an elongated hole where the pedal pivot bar enters the bracket. Anything that would allow play in the pedal. I had that on my old F250, and had to pull the pedal up with my toe all the time.