Hello all.

First off, here's the history as best I know. The truck is an '86 2WD that originally had an I6 mated to a floor shifter 3spd. It has a hydraulic clutch. The truck now has a 351W out of a 1978 Econoline van. It has the seperate clutch bellhousing and then a 4spd manual hooked into the back of that. I took two codes off the side of the trans:

RF-E5TR-7006-AA
C-2605524

Here is the issue. When cold everything works fine, but after only a couple of minutes, the truck grinds into reverse and once everything is at normal operating temperature, the truck slams into reverse, as in the tranny grinds and the whole truck shudders even though I have the clutch to the floor. Also when warm, it also will not go into first when the truck is completely at rest, nor will it go into 2nd. If I do get moving in 1st, it will then lock it into 1st gear and I can't pull the shifter down to 2nd, often when it does finally move out of gear, the whole truck shudders or often the truck will surge with the clutch fully depressed as is if it's partially grabbing.

I started looking through my Haynes manual and it said the pre-'87 trucks have a sealed hydraulic fluid clutch system. Is that why I can't get the cap off the clutch master cylinder on the firewall? It doesn't budge.

Or is it not a lack of hydraulic fluid pressure at all, but a toasted clutch? Are there some other wear parts involved that can affect this? I tried to search the forums and I found some enlightenement, but I'm still pretty lost.

Right now, I just shut the truck off at stop signs and traffic lights because the shifter moves great between gears with the engine off.

 

They say the system is not serviceable, and must be replaced as a complete unit, but the parts stores don't sell the complete system, they sell the clutch master cylinder and the slave cylinder seperately. So you must be able to bleed the and repair the system. It works just like the brakes, so you need to get the air out.

 

LMC do have a complete sealed system listed ($189) but they show it as a 92-96 item. Page 111 in the 80-96 section

 

Thanks guys. So from the syptoms does it sound like clutch fluid pressure? Silly question maybe but would the cap for the hydraulic clutch master cylinder on my truck be a threaded twist off cap or a pop-off cap?

Side point, but how many different 4 speed manuals were there? Do those numbers up above help identify my transmission?

 

Is the slave external of the tranny? This would help. Somewhere when the body style changed, they put them inside, the hydraulic line goes into the bellhousing/tranny. If it is external, Yes they (the master or the slave) can be changed independently, but as stated before, all air must be bled out like brakes. The hydraulic line is held into either piece with a roll pin, with an o-ring inside.

I gues my only other question would be how does your clutch "feel"?

 

It is an external slave cylinder, but it has no bleed screw that I can see anywhere. The clutch pedal is heavy, sitting with it depressed for any amount of time tires the leg real fast. Sometimes though when it's giving the trouble I've mentioned, it almost looks like the clutch pedal moves up further on its own, but I haven't been able to verify yet whether its sticking or returning slowly.

 

I looked at my Ford parts CD thinking you might have some of the same problems that I did with my '87.
But it seems your clutch setup is entirely different than mine.
What I can say is that there appears to be bushings on both the pedal pivot shaft, and where it attaches to the M/C pushrod.
You might check these for wear, as that could be using up a lot of your pedal travel.

 

From your symptoms, your clutch is definitely not disengaging. I haven't worked on your specific unit, but you may be able to get someone to push pressure on the clutch pedal, while you loosen the line to the slave and see if any air comes out. See if there is a bleeder screw on the clutch master cylinder. If there is no bleeder, then you can loosen the line there and bleed some too.

 

My 86 I6 has the 4 speed OD trans. I had similar problems when I first bought the truck. The previous owner thought the cluch was shot and so did I because the pedal travel was so low. The only way to shift into reverse was to shut off the truck just like you are doing now.

I also could not remove that darn cap from the resivour to check for low fluid. I was able to remove the cap with a rubber strap wrench. Turns out the fluid level was fine. The problem was with the clutch pedal itself!

Long story short, if you can manually pull the pedal back up but it wont return to the fully out position by its self, the connection between the clutch pedal and the clutch rod it bolts to is worn out!

I fixed mine by popping the clutch master cylinder rod off the connection to the pedal rod. That connection has lots of little splines and if you unscrew the 18mm nut and carefully work a screwdriver between the pedal rod and the drop bar it's possible to pop off that part. Now reset the pedal to fully out and reconnect the little drop bar to the clutch pedal bar. Hook up the clutch clyinder rod and you are back in business!

Now you are getting a full stroke to the slave cylinder and fully disengaging the clutch.

Another option would be to find an adjustable clutch master cylinder rod. I had the non adjustable type so my fix was a bit more involved but also effective.

No more trouble shifting now!

Hope this helps,
DEAN

 

I will definitely try that pedal rod to drop bar fix first and then slowly work my way from there.

 

so can you take off the cap for the clutch without rebleeding the system? Mine is super tight like everyone elses and I wanted to check my fluid level, but dont want to have air enter the system.

 

I picked up a rubber strap wrench today, clutch master cylinder lid came off great then. Fluid level looks fine. As I was tightening the lid back on I decided gave the whole thing a good heave towards me and noticed the firewall moves. That entire piece of metal the clutch and brake cylinder attach too is pulling away from the main firewall. Is that a welding fix, or something that can be tightened back together with some drilled holes and nuts and bolts?

 

I took some pics, maybe hard to see the splitting metal in the pics, not sure, but it's defnitely separating along the back seam.

 

It's pretty common.
Ford makes a repair kit w/ a plate and longer studs for that, I'll look back through my posts, I think I posted the p/n.
It's abt $12 IRRC.

 

OK, I've got 21 years of receipts in the file and can't find it right now.
I DO know that at the time I bought both a adjustable clutch m/c pushrod and a flanged triangular plate, that came with two longer studs for the m/c and 3 bolts with self locking nuts to bolt it through the firewall.
My clutch release was non existent too.
I can take pictures in the AM when it gets light out....