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Clutch won't disengage

Riotnrrd

Tennessee Chapter member
Hi guys (and gals)

Finally got all of my suspension components changed (ball joints, u joints, wheel bearings, etc)

1979 F150 4x4, 3 speed manual.

I didn't explicitly touch any of the transmission components, but now I have a new problem.

Everything is back together, and I start the truck. Now there's a little bit of grinding when I put the truck in gear with the clutch fully depressed, and the truck IMMEDIATELY begins to move. Its like the clutch isn't fully releasing, despite the fact the pedal is on the floor.

I guess what's confusing me, is that I didn't have this problem before I started messing with the suspension!

The only thing I can think of is that I removed both axle shafts to do the ujoints, and possibly some fluid leaked out of the front differential. But this doesn't make sense as the transfer case is in 2 wheel high, and both front manual hubs are in FREE position.

Now, given that I just messed with the suspension components, can anyone suggest a reason why I now appear to have a clutch or transmission issue?

It would be really cool if I could fix it by adding fluid or a simple adjustment somewhere, less cool if I have to take more stuff apart!!!

Any suggestions please?
 

Riotnrrd

Tennessee Chapter member
Took a couple of quick measurements...

Free play feels like about an inch, which I believe is within the specification of 3/4 to 1"?

Total pedal face to floor distance is about 8 inches. Spec says 6 3/4 to 7 is correct, so the pedal is a bit far out. Could this be the problem, or would reducing this distance make it worse (or better)?
 
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gsxr1238

Be fast.....or be last.
Set the adjustment to about 1.5 inches of free play.Check all your alignments on the linkages.Sounds like something is off just a tick.
 

Riotnrrd

Tennessee Chapter member
OK, messed around with it some today.

Extended the clutch release rod to its maximum distance (all the way out), still not disengaging the clutch.

Pictures below, click on a thumbnail to link to the fullsize one (theres a total of 6 pictures in that album)

(Link to all 6 pictures here: http://s20.photobucket.com/albums/b224/Riotnrrd/Truck Clutch/ )



Kinda looks like this nut is welded on the back?


Does anyone see anything strange in these photos? Please, let me know if so! Suggestions would be very much appreciated!
 
That stuff ain't original, as you prob'ly knowed-already. :)

http://www.panix.com/~alvinj/file12/crayon.jpg
I extended my "crayon" by welding a motorcycle wrist pin
to it. I stuffed a stainless steel bolt in it to keep it straight
while I welded it up (on the 2nd attempt! ;).

Here's a couple pictures of clutch stuff I took for a guy, but
his was the older pivot stud setup so couldn't use 'em, you
my not be able to either?...
http://www.panix.com/~alvinj/file12/clutchfork.jpg
http://www.panix.com/~alvinj/file12/clutchpivot.jpg

There isn't anything wrong with your clutch you can't figure
out and fix! :) Just work at it and maybe get some help to
push the pedal while you watch what's going on underneath
with the inspection cover off? :)

Alvin in AZ
 

73F100Shortbed

That's how we roll!
5,937
320
NJ
I like how you extended that Alvin. I always wonder if mine will fall apart while driving because it seems to short. I may have to do this just for the piece of mind even though I've had zero problems with my clutch.

Like Alvin said your clutch adjustment is far from original. It also looks bent in the picture. Maybe try a longer piece of threaded rod and see what happens.
 
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I'd try Alvin's suggestion and have someone get inside to work the clutch as you lay underneath to see what's going on...could just be you knocked something loose (maybe a spring?)
 

gsxr1238

Be fast.....or be last.
Do you have any slop or excessive wear in any of the linkage components?Any bushing slop in the clutch pedal assembly bushings or worn linkage ends?Are the holes for the linkage rods in the pedal assembly or the equalizer bar worn or elongated?Do the nylon bushings in the equalizer bar and the pivots they ride on show abnormal or heavy wear?Any or all will add to geometry problems for the clutch to work properly.That adjustment bolt on your equalizer bar is a standard Ford part.Have the same setup on my '78 F250.You need to take the nut off the end,and thread in onto the adjuster behind the push tab on the equalizer.It is a jam nut.Ford says 3/4" minimum for freeplay,and 2" maximum.The manual states that 1 1/2 inches is their preference.Wanted to add that there is a spring missing in that picture of the release arm at the bellhousing.Should attach in the arm and attach forward to a point on the frame.
 
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Riotnrrd

Tennessee Chapter member
No idea how old the clutch is... the whole truck is new to me :)

I removed the return spring prior to taking the pictures (when I was adjusting it). There is a spring that runs between a bracket and the clutch release arm that's not shown in these pictures, but it is there and it works.

I had considered that it might be a problem with the clutch itself and not with the linkage. The linkage does move back and forth, I had my wife sit inside and stomp the pedal a few times. I'm just not sure if its moving back far enough.

One thing I thought to see if its a problem internally to the clutch, was to just wire the release arm towards the rear of the truck and start it up, and see if it still drags. If it continues to catch with the release arm all the way back, that would probably mean I have to open up the transmission, yes? But if wiring the release arm back releases the clutch, its a problem with the linkage? Does this sound like a good test?

The linkage components appear to be in fairly good shape. There's not a lot of bushing slop, the ends of the rods dont look too worn, but I'd probably be looking towards disassembling this stuff if it turns out to be a linkage problem (see above test). LMC truck has replacement bushings, etc, and they are less than 10 dollars. The rods are a bit more expensive but still in the 10-20$ range.

gsxr1238: The parts on my truck look a little different from the pictures of replacement parts that I have found online or in catalogs. The metal block between the nuts appears to be a thru hole, which slips back and forth on the adjustment rod. The nuts hold the block in place. When you say "You need to take the nut off the end,and thread in onto the adjuster behind the push tab on the equalizer.", I don't know what a push tab is... don't suppose you have a picture?

Thanks for all of your help, everyone, if you need more pictures or info let me know.

I do have one final question: for the clutch release lever, is it possible to move it back too far so that it will re-engage the clutch plate, or will the lever generally stop when it gets all the way back?
 

73F100Shortbed

That's how we roll!
5,937
320
NJ
What he is saying was the nut on the equalizer bar closest to your oil sender line needs to be threaded on the rod where the other nut is. The second nut keeps the first one from spinning on it's own. If you look in Alvin's picture you will see the two nuts together they do that to keep from loosing up from vibration.
 
One thing I thought to see if its a problem internally to the clutch, was to
just wire the release arm towards the rear of the truck and start it up, and
see if it still drags. If it continues to catch with the release arm all the way
back, that would probably mean I have to open up the transmission, yes?
But if wiring the release arm back releases the clutch, its a problem with
the linkage? Does this sound like a good test?

...the clutch release lever, is it possible to move it back too far so that it
will re-engage the clutch plate, or will the lever generally stop when it gets
all the way back?
Yeah, it seems like you can make a funny noise come from the system when
the main lever moves the pressure plate levers "too" far, but it won't hurt
anything during a test. At least when I've had clutches make that sound
nothing was hurt, I just re-adjusted it and it was fine.

The test you've come up with sounds like a great idea to me. :)

( no need to "open up" the transmission ~ just "pull" the transmission ;)

Alvin in AZ
 
If the throw out bearing is binding or rusting on the input shaft of the transmission, You could have easily bent the the fork where it connects to the throw out bearing.


Alvin, Have you got brother's named Simon & Theodore ?



.:wasntme:
 
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gsxr1238

Be fast.....or be last.
Shortbed gave you a better description than I did about the jam nut.Nothing looks out of alignment or anything?You can remove the clutch release fork and have a look at it.You can also pull the dust cover off the bellhousing that the clutch release arm goes through and have somewhat of a look at the throwout bearing assembly.Does the clutch itself make a lot of noise?
 

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