Fluid level is full and I do have factory cruise. I will look into trying to over ride the saftey switch.

Are the master cylinder clutch rods adjustable on these trucks? If so how? It seems like it is just to short.

 

Okay, here we go. Let me preface this with there are very few things on these trucks I hate, but I hate the joke of a hydraulic system these clutches use. Even with all new parts they are horrible to get working right.

Anyway, the master cylinder provides the hydraulic pressure, the slave receives it. If there is a problem with the slave or the supply line it will leak. If the slave isn't leaking, it's okay.

That leaves the master, if it builds pressure like it should it's 'just' a matter of bleeding the system. Which is a HORRIBLE NIGHTMARE. You can pump, build pressure, open bleeder screw, drain air and fluid, and repeat until the cows come home. No matter where in the word the cows are located. It still WON'T WORK. I've found the trick to be, bleed it as much as you can, then use the slave to push the fluid and air back up the line. Just push on the clutch actuator arm to push the slave rod back into itself. Repeat this and the normal bleeding process until clutch works decently. Refill reservoir repeatedly, it is very small. Then after a couple of days of driving it around the remaining air will work it self upwards and out.

If none of that helps, your MC is junk.

 

No, neither push rod is adjustable.

 

I take that back. I know some of the very early '80s were adjustable, but not the later ones. I just looked at one of my old master cylinders and it does have an adjustable rod so that early design may have carried over into some of the replacement parts.

 

Thanks for the info Chevy_Eater. The clutch system hasn't been opned as far as I know. I will try bleeding it and go from there. I hope to figure it out soon. I see no leaks either.

 

I read some where that ford did make adjustable slaves to correct the fire wall felxing, but I don't know where to get one.
My way to bleed the air out of the system is fill the slave before you put on the line with fuild, install everything then pump the pedtal, you have to start with you hand because you have to pull it back out every time. once it returns out on it's own you pump it with your legs until it works, normaly about 70 pumps will do it

 

Last night I decided to try and bleed the clutch system to see if there was any air. I removed all fluid in resivor first then filled with new fluid. I had a friend help me pump the clutch while I opened and closed the bleeder. I did this till I got Fresh fluid. The master cylinder never went dry. It seemed to help slightly. When I have the clutch pushed in and go from 1st to reverse I can see the truck move slightly. It is still hard to shift. My fire wall will move slightly. Not enough to where I'm worried. I do plan on ordering a brace for it. The clutch fork only moves 3/8 of an inch. This is at the outer end of it. Is this enough movement?

I am trying to figure where to go from here. I did buy new slave cylinder and clutch master cylinder. Just they both were made in China and I really don't want to use them. I used a jumper wire to fix my issue with the hard starting on the clutch safety switch.

How can one tell if the clutch it's self is getting weak and not fully disengaging? I really don't want to pull apart trans unless I have to. It feels strong and when I give her the skinny pedal it doesn't seem to slip. Now it will shake a little when backing up. Never had any other manuals do this.

 

AFAIK, clutch fork movement should be at least 1/2" at the outer end. I don't know about your era of truck, but keep an eye out for a complete master-line-slave pre-built assembly. Pre-filled, bled, shipped sealed. Waaay easier to install, no bleeding, works the first time out. But you'll want to stop that firewall flex; it could one day turn into a firewall crack, and it's def. having a negative impact on the slave travel.

So, it's hard to follow from the thread, but you have a new pedal box with good bushings, and stud and bushing that interface with the pushrod are fresh? And the pushrod eyelet is NOT ovaled out?

Does it still require mashing the pedal to the floor to get the starter to engage?

 

I responded in red to your questions to make it easier.

Thank you all for the help. It is great that you are willing to help out. I hope someday I too can help some one here. I don't have the extra money to just throw parts at this truck and I really do enjoy it from what little I have driven it. I need to figure out soon what I'll be doing with all my trucks as I can really only afford to keep 2 of them.

 

YOIKS, $250, I wonder what the difference is between the years/generations. The one for the OBS PSD range from $100-150; I think I paid $120-ish for a complete kit for our '95.

To answer your question about the whether the clutch itself is weak, you won't really know until you can get more fork movement. If the fork moves the full 1/2"-9/16", and the clutch is still dragging, that would indicate weak fingers on the pressure plate (i.e. new clutch time). It's not conclusive, but since it appears you have insufficient movement of the fork, your problem is more likely "upstream" - hydraulics, firewall flex, etc.

 

The brick noses have a master that bolt from the inside of the cab and the obs bolt from the outside. the brick noses are a pain to get in and out and some of the brick noses have longer lines to the slave

 

I wonder why a person couldn't use an OBS (92-97) master cylinder. If new holes needed to be drilled big deal. The overal design of the 7.3L & ZF trans didn't change did they? I would be willing to redrill holes to save $100+.

If I have time I think I'll try to replace the master clutch cylinder. Seeing as I have no leaks on the slave. I read somewhere that the master could leak past the orings and never so signs externally.

 

IIRC, the OBS have the studs for the clutch master built into the pedal box, which serves as part of the firewall reinforcement. Actually, what would be a cooool mod would be a reinforcement like the Terrapin product, with studs built into it for the OBS-style master. It would indeed probably require a slight mod to the firewall, but that would give you the best of all worlds; a pre-built OBS era hydraulics package, an easier hydraulics install, and a reinforced firewall.

 

FWIW my system failed shortly after getting my truck. I replaced both the M/C and S/C with cheap-o junk from Kragens (Back when Kragens still existed, lol.) IIRC I got not quite a year on it and the S/C popped its guts. (There's a not a pretty story because of this, but I digress....)
I replaced it with a Motorcraft one to find the M/C was no longer able to build up enough pressure to release the clutch. (M/C was replaced too I remind you.) I replaced the M/C (again) with a Motorcraft also. After all the terrible headaches of getting it bled and working it's been going fine for 5+/- years now. Moral of the story, cheap crappy parts in this cheap crappy system = BAD.

I was lucky though and found my parts on ebay, looks like Motorcraft isn't so easy to find on these items.

I recently saw a thread on Oil Burners that someone had found replacement cylinders made out of metal. Not sure if this would necessarily equal better/sturdier parts, but it may be worth looking into.

 

i get mine through napa not cheap, but i haven't had trouble. but the ones for the 150s go with motorcraft.
If I was you I would go to a u-pull it yard find a truck that is still together have a friend measure the slave movent and if you find a good one take it out in one piece.
It doesn't matter what engain the junk truck has just that it has the same trans as yours