3 Speed clutch issue...

[BabyBlueUti]

Hey guys- this my first official problem I'm running past you for help. My 1968 Utiiline (step side) 225- three on the tree hasn't been driven for about 10 years so Im replacing and rebuilding the hydraulics. I rebuilt the Clutch master cylinder and the Clutch slave cylinder and bled them till I had a rock hard pedal when the slave is clamped closed. now the slave properly extends and it appears that everything is working correctly. My problem is that the gears grind when I try to put it into gear. I can easily drop it into gear when the truck is off, but not when it's running. Any suggestions are appreciated!

[PwrWgnDrvr]

Pull the dust cover off the bell, have someone step on the pedal while u observe the pressure plate and disk. Verify that it is disengaging and the disk is free from the flywheel. After 10 yrs it is possible that all is corroded and stuck.
Or put it in gear, engine off, step on the pedal, turn the key to start. Truck will lurch if the clutch is not disengaged.
There is also an adjustment on the rod between the slave and clutch fork arm. Slave might be extending, but not actuating the arm.

[BabyBlueUti]

thanks-'ll get a buddy or the wife to hit the pedal a few times later today when it cools off a bit. If it is corroded and stuck, is there any way short of disassembly and replacement to "unstick" it? BTW it does lurch forward when put in gear when turned off and then the ignition is engaged.

[PwrWgnDrvr]

thanks-'ll get a buddy or the wife to hit the pedal a few times later today when it cools off a bit. If it is corroded and stuck, is there any way short of disassembly and replacement to "unstick" it? BTW it does lurch forward when put in gear when turned off and then the ignition is engaged.

Does it lurch with the clutch pedal depressed?
Most likely u don't have it adjusted correctly.

[BabyBlueUti]

nothing much happens with the clutch pedal depressed. If I try to put it into gear It grinds and won't go in unless I jam it in by force. but when it's turned off, It will go into position with no problem. An additional problem I have is a loose washer at the linkage end. I'm keeping it in place with a pair of vice grips right now, but is there a cotter pin or something that's supposed to keep it in place? Until I can get it up on some ramps, I can't get close enough to see...

[BabyBlueUti]

Ok- got under there and after scraping through a half inch of 48 year old crud, took off the "dust" shield and checked the performance of the clutch.
before the clutch is pressed, the friction plate is squarely against the flywheel and whatever pushes it there is tight against the friction plates back side. Once the clutch is pressed, the friction plate stays tight against the flywheel, but a 1/16 gap opens behind the friction plate and whatever holds it up against the flywheel normally. any clues? is the friction plate supposed to be disengaged from the flywheel? I know nothing about clutches, so any advice is helpful.

[Jim100]

Could this be a situation where the end of the trans input shaft could be stuck in the pilot bushing? (crank shaft)

[BabyBlueUti]

How could that be checked without disassembly? also- is the friction plate supposed to be up against the flywheel when the clutch is disengaged? it is bolted to the flywheel directly or should it float freely unless the clutch is engaged? If it is, then I'm wondering if it's stuck up against the flywheel due to sitting too long. everything in there seems relatively dry and surprisingly clean aside from dust.

[712edf]

You have a flywheel, then a clutch disc, then a pressure plate (or friction). The pressure plate is bolted to the flywheel, they always turn together. The disc is sandwiched between the two, but when the pedal is depressed, the friction surface of the pressure plate moves AWAY from the flywheel (but keeps turning with the flywheel). When the friction surface moves away it stops "squeezing" the disc between itself & the flywheel, thus allowing the disc to stop rotating & remain stationary while the flywheel/pressure plate keeps rotating. The disc is attached to the splined input shaft of the transmission.

I suspect that while the one side of the disc becomes "free" (from friction surface) when you depress the clutch pedal, the other side of the disc is still stuck (to flywheel). I may be off in my diagnosis specifics, but I bet your disc isn't free on both sides when pedal is down.

Are you able to take the vehicle to a vacant parking lot, start it in gear & drive it?

Bucky

[712edf]

Here's a generic picture of what I'm talking about.

The outer edge of the pressure plate is bolted to flywheel. The friction surface moves away from flywheel & stops squeezing the disc when pedal is depressed.

Bucky

[BabyBlueUti]

Thanks! that's what I thinking somehow the friction disc is adhering to the flywheel and not disengaging- Keeping it from allowing me to put it into gear while running. I wonder what I could slip in there to break that free… a very thin putty knife or something that I can tap in without scratching the flywheel… it would have to be paper thin… or maybe tapping on the edge of the disc with a rubber mallet… I just thinking out loud here… It's not like I can squirt WD-40 up in there, but there has to be a logical way to separate them without much damage.

I live in a subdivision and don't have a trailer to transport it to a parking lot, and I'm a little unsure about the brakes…. I replaced the MC and a few lines, but haven't changed the wheel cylinders yet. I don't want to get going and not be able to stop!! Hopefully I can get those changed out this week. It's hot in Atlanta this week, so Im just able to work in the mornings and into the evenings after about 7pm. Otherwise I'm sweating so much my glasses get fogged over.

[PwrWgnDrvr]

Put it in gear. Apply the parking brake. Step on the clutch pedal. Start the engine. If its stuck, that will either break it free, or u won't be able to start it.

[BabyBlueUti]

I like it. I'll give that a shot tomorrow am and report back. Thanks for the great advice.

[BabyBlueUti]

Sad news. Total fail. apparently the E-brake is useless. I just had a nice 15 foot drive up the driveway and back. Good news is that my regular brakes are functioning ok otherwise I would be parked in the living room. Baby Blue wanted to fire right up in reverse. maybe I'll try the mallet and a paint scraping tool. That has a flared edge that probably would not scratch the flywheel.

[Noelie84]

If you're trying to avoid taking it apart, you can always try the old 'farm' approach.

1) Put the truck into 3rd gear (engine off)
2) Hook a tow strap to the frame and the other end to a buddy's truck.
3) Have them tow you, engine off, key off, in 3rd gear. Pump the clutch pedal repeatedly while this is happening.

The back wheels will be trying to drag while you're doing this. Usually pumping the clutch pedal will transmit enough of a shock to the friction surface to free it up. We used to have to do this every fall with my parent's plow truck because it sat all summer long. Once we freed it up it worked great all winter, but it always stuck over the summer again the next year.


If this doesn't work for you, probably the only solution will be to take it apart. But, this has worked for me 100% of the time in the past when I've had to free up a seized clutch.

[my5thmopar]

You're overthinking this. Push in clutch. Putty knife tip "easy" against the fly wheel or plate "not disk". You really have to be strong armed to damage it. Gook luck.

[BabyBlueUti]

The putty knife goes in like butter its clearly not stuck to the flywheel. next thought is the linkage. I checked and there is NO bushing on the linkage at the Tranny end. That gives a whopping 1/2 inch of play from end to end… could this be the problem? if so, then why does it go into gear when the truck is off??? I'll still try the towing test to break it free if there is some mysterious power keeping it stuck… BTW where can I get the bushings for the linkage. I went to 3 stores with no luck.

[BabyBlueUti]

SOLVED. Thanks for all the suggestions guys. I used the back side of a hacksaw blade to slip in all the way to the center and all around. fired her up and she had one quick grind when dropping into gear and then was free. engages in all the gears without grinding and no sticking. On to the next problem--- remove and replace the badly broken exhaust manifold.

[Noelie84]

SOLVED. Thanks for all the suggestions guys. I used the back side of a hacksaw blade to slip in all the way to the center and all around. fired her up and she had one quick grind when dropping into gear and then was free. engages in all the gears without grinding and no sticking. On to the next problem--- remove and replace the badly broken exhaust manifold.

Glad you got it.

Time to start bloodying your knuckles on something else now!

[scottcab]

Thank you so much for coming back and updating the post when you found a solution. I was able to use a very similar solution for the same problem and now my 1966 D300 is back up and mobile.