Low Clutch pedal / Cluch enagement problem

[BigFoot]

First post here:

Hi,
I have a 71 F250 sport custom with a 360. I'm having an issue with the clutch. The pedal seems to be be getting lower and lower to the floor. Now I can barely get down far enough to engage to be able to shift with out excessive syncro wear. Today my choke was stuck on high idle and between the two problems I barely got it home. Typically with a low pedal I'd think the clutch was going bad or a hydraulic issue but since this is a manual clutch and also that the truck seems to have no problem engaging the engine to the drive train (I stalled a few times and also was able to lay rubber) I'm kinda puzzled. The floor pans are both really rusted out. Front passenger cab support its gone. I have read that having a sagging cab could cause pedal problems but I cant imagine that this would be caused by that. Is there some adjustment either under the dash, hood or at the fork? It was cold, dark and I was fairly pissed off when i got home so I decided not to look tonight, but post this and the look in the morning with a more educated eye.

It seems this winter has been tough on ol' BigFoot. First it was the turn signal cam, then a new thermostat, coolant hoses, then a hole in the new radiator spraying all over the old cracked ignition wires causing misfiring, fuel pump went out, then today the damn high idle, the clutch problem and at the same time the power steering seemed to be failing! Pretty soon there wont be any thing left to fix in the cold winter air...

Any advice? Thanks in advance!

Jeremy

[Art]

Rotten and sagging cab will cause clutch adjustment problems. As the cab sags lower, the clutch pedal travel needs to be increased. You may be able to lengthen the adjustment (the link that pushes on the fork) to compensate for now, but solid cab mounts are the only permanent fix. If you adjust it, make sure the pedal freeplay is maintained otherwise it will get expensive to fix.

[BigFoot]

Rotten and sagging cab will cause clutch adjustment problems. As the cab sags lower, the clutch pedal travel needs to be increased. You may be able to lengthen the adjustment (the link that pushes on the fork) to compensate for now, but solid cab mounts are the only permanent fix. If you adjust it, make sure the pedal freeplay is maintained otherwise it will get expensive to fix.

Well crap. I really cant see replacing the floor pans and cab support because of excessive rust at the bottom of the firewall and rockers where the new floor sections would weld too. I'm guessing that in the long run im looking at either a cab off resto or selling it. How much work is it to pull off the cab? that would really be the only way to fix it right. Any other advise? Also, how much pedal freeplay is there supposed to be?

[wildcard]

Mine done almost the same way, as far as having to push all the way to the floor. The problem was the clutch rod had cracked at the end going in the pedal. It broke before I figured it out and then I had no clutch. The pedal was just hanging there. With it being up under the dash, it's not noticeable until it's too late.
Just something to check.

[Nitekruizer]

I had the linkage "Z-bar" break on my first car. It would be an idea to check all of the rods, pivots, etc. As for free play, I would go with 1.25" to 1.5" of pedal travel. IHTH

[bjde0b]

I had the adjustment pin push through the lever with the nipple recess. This would just take some mechanical fixing if you don't care about pretty.

Check your clutch adjustments and if you are against the figurative wall, cut your rod and weld it back together, longer or shorter whatever you need.

[BigFoot]

I had the linkage "Z-bar" break on my first car. It would be an idea to check all of the rods, pivots, etc. As for free play, I would go with 1.25" to 1.5" of pedal travel. IHTH

Just to be clear, "Free play" would be the distance the pedal travels from the top most position until you feel resistance. (the feel of the throwout bearing making contact with the pressure plate) Correct?

And thank all of you for all the other info. This weekend I will limp it to my back alley and investigate all the linkage.

[Nitekruizer]

Yes. Good luck

[Art]

Couldn't reply earlier, but now it will let me.

When I first got my 1969 F100 back in 1989 the cab mounts were gone. I mean gone to the point that the steering column was binding up, since it was the only thing left holding up the front of the cab... That was the main reason the truck was was cheap - and being a college student at the time - cheap & ugly was exactly what I really needed for commuting to downtown Milwaukee for classes.

To solve the cab problems with that truck, I fabricated bolt-on cab mounts that went over the top of the existing swiss cheese / air that was there. They extended further up the firewall to reach sound metal. That meant going past the firewall to floorpan seam that is visible in the engine compartment. I vaguely recall them being around 0.090" thick or so - quite heavy duty. I only removed the front tires and built it all with the cab and fenders still attached. 4 years later I graduated and then rebuilt the truck with rust-free sheetmetal. Finally, no more barn-door hinges on the hood

You can do something similar without removing the fenders or the cab. If you insist on removing the cab, you can do that also with the box still attached to the frame. I have done it before when scrapping out rusty trucks. It is just that most people are removing / replacing the box anyways if they are going through the work of removing the cab. Additionally, removing the box makes a little more wiggle-room for the cab.

Clutch adjustment spec is 1" to 1.5" pedal free travel at the pedal pad per the service manual.

[BigFoot]

Couldn't reply earlier, but now it will let me.

When I first got my 1969 F100 back in 1989 the cab mounts were gone. I mean gone to the point that the steering column was binding up, since it was the only thing left holding up the front of the cab... That was the main reason the truck was was cheap - and being a college student at the time - cheap & ugly was exactly what I really needed for commuting to downtown Milwaukee for classes.

To solve the cab problems with that truck, I fabricated bolt-on cab mounts that went over the top of the existing swiss cheese / air that was there. They extended further up the firewall to reach sound metal. That meant going past the firewall to floorpan seam that is visible in the engine compartment. I vaguely recall them being around 0.090" thick or so - quite heavy duty. I only removed the front tires and built it all with the cab and fenders still attached. 4 years later I graduated and then rebuilt the truck with rust-free sheetmetal. Finally, no more barn-door hinges on the hood

You can do something similar without removing the fenders or the cab. If you insist on removing the cab, you can do that also with the box still attached to the frame. I have done it before when scrapping out rusty trucks. It is just that most people are removing / replacing the box anyways if they are going through the work of removing the cab. Additionally, removing the box makes a little more wiggle-room for the cab.

Clutch adjustment spec is 1" to 1.5" pedal free travel at the pedal pad per the service manual.

Thanks for your comment. I am now pretty sure that you and I have experienced the same problem. I hadn't thought about the steering column binding but i think mine is doing the same thing. I had blasted over a couple of speed bumps and I bet that's what did it. I didn't put all of this together until you mentioned the steering. So the sagging cab is causing my clutch problem, my steering problem and my high idle problem. WELL CRAP.

[BigFoot]

So, I fixed the problem! I just welded up some plates to some 1" square stock and ran supports down to the old bushings on both sides. I bolted them to the 3 bolts at the top of the firewall where the inner fenders mount to the underhood cab. It worked very well. Now I'm tackling my next problem. Repairing the damage to the steering caused by the sagging cab. See my next thread here: http://www.fordification.com/forum/view ... =5&t=71827

Thanks for your help!

[tbone6]

Thanks for the follow up!