Clutch adjustment,,,,,,

Pull. The old style pressure plate with the ring that looks like a toothed starter ring gear and the lock that has angle iron stub and two 9/16’s head 3/8 thread bolts holding it on. My guess it was last installed in 1992. Got around 680,000 on it if so. Has Eaton cast in it but other then that I don’t know what the model # would be. Very easy on the leg and doesn’t grab to harsh like a ceramic can do.

 

Organic

 

I can't say that I have experience on a 55-72 diamond t or pete. But if it has a angle spring clutch and clutch brake. I gonna assume it has a pedal stop and return spring. Which is still linkage and effects air gap between fork and bearing.


Now since I'm not of that vintage. Did some of the multi box trans not have a clutch brake, and you put aux box in gear to stop rotation, then you put main box in gear? Acting as a brake?

 

Yes. The brake was more of a road ranger thing. Most early spicers didn’t use them. You just gently pulled them in gear. The aux. box usually had enough friction in neutral to stop the output of main at idle. One trick that was common was to leave the main in high gear and aux in neutral at fire up to get trans oil warmed up. Some guys would leave main trans in gear all the time at a stop with aux in neutral. Light turns green quickly push in clutch put aux in a gear and go. No grinding or clashing at all that way. On the fly releasing the clutch is not needed for aux shifts at all

 

From a Pete. The pedal stop is the plate where the paint ends. It has a rubber pad that seals on the toe board of firewall. The spring just hooks to a tab on the framerail. No real external adjustment.

 

Under the hood next to the internal tube steering shaft and brake valve.

 

I was only a kid. But recall dad had a transtar with a 6x4. He always warmed up the box. 238 and on hendrickson. Needed all the help it could get pulling Michigan trains.

Gramps, Step Gramps had a cabover Reo with a transplant BIG AL. Spicer used him as test mule for a 14,or 16 air shift Spicer. I heard it ran real well. Leased on to Hennis, or Cooper Jarret most his time. He just passed last summer at 97.

 

But still did its job. As cool as it is. Not relevant to modern clutch adjustment.

 

It’s pretty easy, once you do it, you’ll see. Chances are you have a newer style clutch. I believe the adjuster is a 5/8” bolt, spring loaded. Take the inspection plate off. Have your helper bump the starter over, till you can see the adjuster. Have helper hold pedal to the floor. Using a box end wrench, or a ratchet and socket, push in on the spring loaded bolt to unlock it, might have to wiggle it back and forth a bit, to get it to unlock, push it in, while holding it in, turn it clockwise about 2/3- 3/4 of a full turn. Release the spring loaded bolt. Might take 2-3 times, if using a wrench, since you can only get about 1/3 of a turn each time. Make sure bolts locked back into place, might have to wiggle it a bit, till it pops back out. Once it’s popped out, it’s locked and shouldn’t turn. Release Clutch, Check freeplay, repeat till correct. If you get it over adjusted,(too much freeplay), you can simply back it off counter clockwise, with the clutch depressed, again making sure the bolts locked in before releasing the clutch. Often when a clutch needs adjustment, not only will you lose free play, but also clutch brake. Adjustment should also restore clutch brake. Usually 1.5”-2.0” measured at the pedal in the Cab is considered good freeplay. Over adjusting it for extra freeplay can weaken the Clutches clamping force, and shorten life. 2” max is OK. Ideally gaps should be 1/2” between the throwout/ clutch brake, but can be up to 5/8”. Gap at forks/ throw out should be 1/8” with clutch released.( That’s where you’re actual freeplay comes from). If all is good, the 1/2” (5/8” max) measurement, should result in 1/8” gap at forks/throwout. Giving you the proper freeplay, and clutch brake operation. If for some reason, you can’t get Clutch adjusted within the 1/2”-5/8” throwout/clutch brake range, you may be out of adjustment, and need a new clutch. Or if you get it adjusted within the 1/2”-5/8” range, and have too much freeplay, at the pedal, ( more than 1/8” gap at fork/throwout) and maybe the clutch brake won’t engage, You may have worn/sloppy linkage. If freeplay and linkage are all good, and clutch brake doesn’t engage. You may have a worn clutch brake. Good time to grease the throwout bearing good. Pushing the clutch in a couple times, making sure some of the grease gets onto the clutch brake itself. It’s made to operate with a little grease on it. Grease the fork bushings at outside points. If you want to get fancy, put a dab on the fork tips, where they contact the throwout, if they’re dry. Chances are a simple adjustment is all that’s needed. Bottom line is there’s a proper way to adjust the clutch, checking the 1/2” gap, and clutch brake operation. Free play, though is dependent on proper linkage operation. Worn linkage can cause excessive, or “ false” freeplay, and cause clutch brake not to engage. Bad motor mounts, or Cab bushings can also affect linkage. All things to consider, if the linkage seems to need adjustment. If everything’s good, and clutch was originally set up correctly, shouldn’t need to ever adjust linkage.

 

Hack Saw blade.