Clutch help

[ViktoR]

Ive been looking for guys like you for some time. I understand I am to look for related posts but, have not found anything that pertains to special people like me. Ive got this 94 Explorer (5 speed mazda tranny I presume?)that is driving me bonkers. I just recently replaced the clutch, pressure plate and the mysterious hydraulic throw-out bearing that is referred to as the slave cyclinder

The problem: Gears rake when the engine gets close to operating temperature. As operating temperature rises to normal the gears will not slip in at all (most often and usually at a stop light) and requires the ignition turned off, slipped into first gear and restarted. NOTE: I just replaced a former tranny with the same characteristics that soon burned out.

My question: Why is this happening? I thought I performed the bleed operation correctly. (Pour DOT4 fluid in the top till it runs out the bottom, tighten the bleed screw, and pump the clutch pedal till your legs fall off?) Should I have pressurized the the slave cyclinder "before" tightening the tranny bolts? ( Im thinking the throw-out bearing is already up against the clutch assembly making the bleed operation less effective?) And most importantly, What the heck does heat have to do with it!?!? It shifts smooth as butter when the engine is started after a longggg cool down period, like overnight. AHHHHHHHHHHH!!!!

Thanx in advance.
-Vik

 

[MyExpWork]

I wonder its not the engine temp, but of course as you drive, the engine heat will transfer to the clucth housing and when you drive the clutch is heating up itself through normal useage.

So with regards to the heat thing, my first thought is that there is some foreign material in the clutch assembly that as it warms up causes some sticking problems with the clutch mechanism.

It was working fine before you did the change? As it warms up and does not shift at all, what does the clutch pedal feel like? And how do you shift when at speeds from like 3rd to 4th-does it shift normally then?

I don't have a 5speed explorer but have worked on clutches before, but I have never heard of a "hydraulic throw-out bearing or it being referred to as the slave cylinder". Maybe its just wording differences.

Was everything perfectly clean when you put the clutch in?

Keep us posted because I sure am curious.

Brian

 

[spiper]

First thing that comes to mind is your tranny is overheating. I'm thinking, without actually seeing first hand your problem, is

1. You are low on transmission fluid, or
2. You have the wrong transmission fluid in it, you need to have Motorcraft MERCON automatic transmission fluid in it, although alot of guys swear by synthetic.

 

[IgotTwo]

I replaced all the same on my 94...the installation and slave bleeding is pretty straight forward. You seem to have it down.

Not to mention the obvious but:
Did you check out the master cylinder on the slave unit? off the pedal and under the reservior?

Maybe its tired and the pressure blows by the "o" rings in there after you run it for a while. That may be why the clutch doesn't disengage and you are not getting a "full throw"?

Check the tranny fluid level? or maybe bad synco(s) in the transmission have revealed themselves.

 

[Jason94sport]

I just did this whole thing on my 94. Complete tranny & clutch. Ford intergrates the Throw out bearing into the top of the slave cylinder. It's a complete part.
Could be the clutch fluid lines, the clutch wasn't installed right, or a bad slave cylinder. If your truck was fine before the clucth swap, that should rule out a bad tranny. I would drain the tranny fluid anyway, & refill with the Motorcraft MERCON automatic transmission fluid. If that all fails, then your only option is to tear everything apart again, till you find the problem.

 

[IgotTwo]

MERCON automatic transmission fluid?

In a manual tranny? Pls help on that one.
I may be about to learn something.

Thanks

 

[MyExpWork]

Yes, I think most of the mannual transmissions now adays call for auto mercon III fluid. My ol 1984 Chevy Camaro called for it and no gear oil, I think my 91 Toyota did the same thing.

Brian

 

[Jason94sport]

All trucks are different. The 94 explorer & I think others call for mercon III auto trans fluid. It's on the FAQ on explorer4X4.com, & the helms manual I have also calls for auto fluid.

 

[ViktoR]

Thanx for the great responces.

MyExpWork >It was working fine before you did the change? As it warms up and does not shift at all, what does the clutch pedal feel like? And how do you shift when at speeds from like 3rd to 4th-does it shift normally then? <

No. It wasnt working fine. It will shift after warmup but, the gears rake and the pedal feels just a bit mushy. When stopped at a traffic light is when it will not slip into gear.

spiper >First thing that comes to mind is your tranny is overheating. I'm thinking, without actually seeing first hand your problem, is

1. You are low on transmission fluid, or
2. You have the wrong transmission fluid in it, you need to have Motorcraft MERCON automatic transmission fluid in it, although alot of guys swear by synthetic.<

Well, the heat is certainly doing something. The fluid level is fine btw. Yes it is the mercon fluid.

IgotTwo >Not to mention the obvious but:
Did you check out the master cylinder on the slave unit? off the pedal and under the reservior? Maybe its tired and the pressure blows by the "o" rings in there after you run it for a while. That may be why the clutch doesn't disengage and you are not getting a "full throw"? <

How to check it? It seems to feel fine (stiff pedal) until it gets warm, then gets sorta mushy and unpredictable. No apparent leaks either.

IgotTwo >Check the tranny fluid level? or maybe bad synco(s) in the transmission have revealed themselves.<

Level is fine. Tranny is a reman.

Jason94sport >Ford intergrates the Throw out bearing into the top of the slave cylinder. It's a complete part.>

Mysterious, isnt it? Just like putting auto tranny fluid in yer manny tranny.

Jason94sport >Could be the clutch fluid lines, the clutch wasn't installed right, or a bad slave cylinder. If your truck was fine before the clucth swap, that should rule out a bad tranny.<

Actually, it wasnt fine. The clutch went out first. I replaced the entire assembly with parts from CarQuest, including the mysterious throw out bearing slave cylinder thingamabob. The former tranny was on its way out the door due to major leaks and eventually a hidious whine from underneath.

I want to thank all of you for your responces. In short, I have covered the fluid types and all the parts are new `cept for the tranny which is a reman. Something is definitely going on down there. Something to do with the heat and whatever is going on inside the hydraulic system. There arent any leaks. Ive watched closely for that.

Im going to loosen the tranny this weekend, pull it away just a snidget from the engine and go through the bleed process one last time. (uhg) UNLESS somebody recognizes this riddle and saves me the time and trouble.

Again I thank you all.
-Vik

 

[IgotTwo]

ViktoR
I don't want to take away from your thread.

I'm a little confused
When I replaced the clutch, drained and refilled the tranny fliud in my 94 I used 85-90 weight. I'm sure I checked Clintons (I'm going to check the book again)
I'm also sure it was 90 weight that came out of it.

The transfer case called for Mercon. And I know transmission fluid came out of that when I drained it.

I'm not sure if I'm hearing I blew it or just didn't opt for for a better alternative. Sorry just a little confused.

 

[ViktoR]

Yours is 4-wheel drive Im assuming? Just two wheels here. The guy at the counter told me it takes mercon in the tranny for my model.

 

[MyExpWork]

Did the reman'ed tranny ever work fine? If so, at what point in time did it work well? Before the old clutch went bad?

I still think it may have something to do with your clutch/hydraulic system.

Did you get the flywheel resurfaced? I did a clutch job once without getting that machined and it screwed everything up. The slave cylinder blew, burnt my new clutch plate, etc. The whole thing had to be redone. If that has some foreign material on it, it could be causing your problem since all other parts are new.

Brian