Sticky Clutch Pedal??

[NC_John]

I've got Blue roaming around some now (went two counties over to meet my wife for lunch today which was pretty brave).

One recurring issue that I have is the clutch pedal "sticks" to the floor, seemingly more so when the truck is cold. It does it less when I've been driving a bit but still does it once and a while. The clutch seems to be operating normally otherwise but this is obviously pretty annoying.

I've lubed everything I can see and greased the fitting I found on the horizontal shaft. The assembly looks to be slightly crooked from the frame to the engine/transmission but I don't believe it is actually bent or damaged. I haven't come across another one yet to see if this is normal. The return spring is intact. I might could try replacing it with a newer one to get a stronger return pull.

Anybody had this issue? Any suggestions? I can't find anything binding when inspecting it under operation (though it is hard to tell).

[geezer#99]

Maybe you're over centering your pressure plate. A flat finger diaphram is notorious for that. What clutch set up you got?

[NC_John]

Originally Posted by geezer#99

Maybe you're over centering your pressure plate. A flat finger diaphram is notorious for that. What clutch set up you got?

I've thought it to be stock. I've never had it open yet. PO didn't mention any clutch work being done while he had it.... I guess if I have to pull the transmission to adjust it, it'll have to wait until the engine comes out for a rebuild (coming up later this year).

[geezer#99]

IT's not adjustable. Usually the pedal sticks to the floor at high rpm shifts. THat's why they went to the raised finger pressure plate.
New thought!
Check the over-centre spring under the dash. It's up close to the top of the clutch pedal.
It might have come loose or popped off the pin.

[NC_John]

Originally Posted by geezer#99

IT's not adjustable. Usually the pedal sticks to the floor at high rpm shifts. THat's why they went to the raised finger pressure plate.
New thought!
Check the over-centre spring under the dash. It's up close to the top of the clutch pedal.
It might have come loose or popped off the pin.

Mine is sticking intermittently at stops, usually early in the drive and never between gears. Last time I checked under the dash, everything was OK. I think if the spring came off it would do it all the time.

I was going to put a 5-spd in it when I did the rebuild but I decided I don't want to cut a hole in the floor. Besides that the shifter would go where my right leg sits. The 3-on-the-tree is just not a lot of fun to drive and I'm not crazy about the gearing. Seems to tall for around town and too low for highway speeds (3.07 rear). Maybe I'll just put in an automatic and be done with it. Of course that would add a bunch more stuff I don't want to the engine bay...(kickdown linkage and cooler lines).

I appreciate the troubleshooting help.

[geezer#99]

THought number 3!!! LOL!!
Maybe your motor is twisting to the right and knocking your clutch linkage out of whack making it stick. Bad motor mount could do that.

[NC_John]

Originally Posted by geezer#99

THought number 3!!! LOL!!
Maybe your motor is twisting to the right and knocking your clutch linkage out of whack making it stick. Bad motor mount could do that.

Not likely- it does it with the engine off too.

Here is a picture of part of the clutch linkage that looks bent to me. Can anybody out there with a 3-on-the-tree compare this to theirs? This is the original engine and tranny (numbers matching) so I don't think its been jacked around with.



I just did some more lubing out under the dash. I got rid of a squeak but if I press the clutch pedal hard enough, it still sticks to the firewall. I noticed too the clutch arm is even leaving a mark and wearing into the carpet. Is the clutch depressing too far? Is there supposed to be a stop I'm missing?

[geezer#99]

You should be able to push it right to the floor.
Can you pull the rubber cover off on the rod coming thru the firewall. You might see where it's hanging up.

[MidLifer]

Your z-bar does not look straight. Could it be that the mount on the motor is flipped? It should be 90 degrees to the frame rail.

[NC_John]

Originally Posted by geezer#99

You should be able to push it right to the floor.
Can you pull the rubber cover off on the rod coming thru the firewall. You might see where it's hanging up.

I can't feel it binding there.....

[NC_John]

Originally Posted by MidLifer

Your z-bar does not look straight. Could it be that the mount on the motor is flipped? It should be 90 degrees to the frame rail.

You think the motor is too low? Its level so if there is a motor mount wrong, they both are. I'll take some pics and post tomorrow. Could be that both sides are trashed (probably eaten up from oil over the years)- maybe its got the engine too low and that's jacking up that z-bar. That makes sense to me.

['68OrangeSunshine]

On my '71 4x4 Jimmy [w/350 V8 | SM465 | NP205], the upper arm on the Z-Bar separated from the cross-tube, with the clutch pedal stuck on the firewall. It got stuck in-gear, and was hard to get into neutral to be towed home.
The Throw Out Bearing had worn into an oval inside diameter, after 13 years of hard charging and double clutching.
I had the Z-Bar welded back and the pressure plate and flywheel resurfaced and put in a new T/O Bearing, and it runs again.

So check the weld bead on the Z-Bar upper arm for signs of fatigue. In my case 13 or 14 years ago, I had a machinist 'joggle' the arms on my Z-Bar to clear some headers. Perhaps if he used heat, the welds were weakened and 13 years later metal fatigue happened.

[NC_John]

Here's some more pics.

The engine may be low but it sits level.



Here is the LS engine mount- please compare to your own...



another one of the LS:



Here's the RS:



And you can see how the z-link is jacked up and seems too low on the engine side.

[oklalawnboy]

Mine sets crooked like yours and it doesn't stick to the floor. Could the bearing retainer (part the throw out bearing rides on) have a worn spot and the throw out bearing gets cocked and wont slide back toward the pressure plate? just throwing out ideas...

[NC_John]

Originally Posted by oklalawnboy

Mine sets crooked like yours and it doesn't stick to the floor. Could the bearing retainer (part the throw out bearing rides on) have a worn spot and the throw out bearing gets cocked and wont slide back toward the pressure plate? just throwing out ideas...

Well, that makes me feel better that yours looks the same. Any more like this? This is a 350 with the Saginaw 3-spd in a '70.

I reckon I could disassemble the entire thing and replace wear parts/bushings etc. through it. That sounds like a pretty reasonable approach.

[geezer#99]

A new thought!! LOL!!
Take the clutch rod off the tob fork and then work the pedal to see if it hangs up.
If that never sticks then you know it's from the clutch fork on inside.

[NC_John]

Originally Posted by geezer#99

A new thought!! LOL!!
Take the clutch rod off the tob fork and then work the pedal to see if it hangs up.
If that never sticks then you know it's from the clutch fork on inside.

Now THAT is a good idea!!!!!

[Tom Vogel]

Now mine is a big block mind you, however, my z-bar is level and is also at a perfect 90 degree angle to the frame. I dont think GM would have designed it otherwise. Just doesnt make sense from an engineering point of view.

[NC_John]

Originally Posted by Tom Vogel

Now mine is a big block mind you, however, my z-bar is level and is also at a perfect 90 degree angle to the frame. I dont think GM would have designed it otherwise. Just doesnt make sense from an engineering point of view.

I agree. I noticed right away it doesn't look right but I can't see any reason for it to have been moved with everything stock and seemingly undamaged. I've seen stupider stuff out of engineering though (like that whole effin' vent system between the cowl and the cab....)

[Tom Vogel]

The engine in that truck is a replacement engine (its blue). Someone could have changed something in the swap.

[NC_John]

Originally Posted by Tom Vogel

The engine in that truck is a replacement engine (its blue). Someone could have changed something in the swap.

Which truck - yours?

[wreckedchevy]

here's a pic of mine it's off a stock 69 with 4 speed and v8. mine was a 6cyl truck I put the v8 in the 6cyl mounts with 6cyl stands so it sits pretty close to the exhaust but never sticks. and the linkage is straight.