Full Floater

Good tips on making up a trolley for it. Same with using some all thread. I think in this case I will use some 4x4 wood or steel tubing across the window sills, and remove the floor panel and sling around the front and back of the trans. It was done this way on this truck before according to a previous owner. I just don't have the material on hand to rig up a decent trolly, nor is there a place near by that sells heavy trans jacks. I'd like to get started on the pulling of the trans asap if that's what ends up happening

Thanks fellas. Well, although uneventful and nothing bad happened, I did what was suggested to not do and loosened (about 1 turn) the nuts for the 6 dogs, on the outside of the flywheel through the little access hole for them. With the engine off, I pushed the clutch pedal in and out a few times, then re-tightened the nuts. To no avail. Still acting the same way. I was hoping that would free up a stuck intermediate plate. I'm almost tempted to try it once more with the engine running but that may be a bad idea.... Yes, good thoughts on the pilot bearing. It is brand new in this case and I really hope it didn't fail out of the box!

Lots of scratching my head going on here on this one!!

I would imagine it was done with the dogs in place. I didn't ask. In hindsight I should have but at the time I didn't think anything of it. The flywheel wasn't in bad shape so they just cleaned it up a tad, I was happy with the quality of the surface.

I actually believe this is a new clutch. That's what they sold it as anyways.. I don't have a good enough jack for these trans, I will have to use a chain fall off a 4x4 that's laid across the window sills. Im doing the work on a gravel surface to. Which is why im trying to exhaust all options first lol

Ok, it's making sense to me now. I bet thats what's happening since im getting SOME disengagement but not enough. Probably just the rear friction disk is releasing and not the front. So with the clutch pushed in, I then SHOULD be able to move/wiggle the rear friction disk if I can get to it, correct? It also makes sense that the dogs will just move back if I loosen then tighten them. I think I should at least try that before pulling the pin and dropping the trans....JUST IN CASE it works! If it does I will certainly buy a lotto ticket and will also share it with you fine fellas! If I attempt that.....should I do that with the pedal depressed?

HAHAH. Ok note taken. But when you say no way of holding the dogs, is that in reference to them falling out if I accidently remove the nut, OR do you mean hold them to keep them aligned? I was thinking just loosening the nut about 1 turn or something to take tension off of the dogs and hopefully let them settle where they need to settle, in case one is kittywampus

OR!!! if I loosened the dog nuts thru the access port one at a time, then with the engine off I depress the clutch pedal several times to hopefully align anything that might be out of whack, then retorque them. Thoughts?

So the dogs allow the intermediate plate to move back and forth, correct? I'm not familiar with them in any other application that I've worked with in the past. This is my first Mack trans/clutch operation

Grease is due to not pressure washing everything as good as I should have during install due to it being 10 below during that time. There was a leaky rear main on the previous engine. There is no grease on the new clutch brake however.

Side note, thank you everyone for your dedicated and prompt support. Means a lot. I hope I can return the favor on another topic one day

Sorry I never answered that dog question a few posts back. The dogs are the same dogs that were in the flywheel. The clutch had been replaced at some point recently (thats probably when the rubber mounts were done as well) due to a wore out clutch. There was not much wear on the clutch and the dogs were likely done then also, seeing how there was no noticeable wear on them. Just so things are clear, the reason the clutch was replaced again is due to me having the engine out of the truck and obviously it made sense to throw a new clutch at it while im in there. As for the dogs, they appeared square/aligned when I slid on the intermediate place but I did have to kinda push/tap that plate on. It wasn't totally smooth but also not an apparent problem. There is a side access port on the flywheel housing to access 1 dog nut at a time. I wonder if it would be worth while to loosen each, one at a time; and retorque. In case one is hung up or something

I can't really get a good pic of the clutch brake with the release fork in the way....but it's in there. Kind of sitting "loosely" in the keyway of the input shaft that is slide in on

The clutch brake is the same brake that was in it when I pulled the old engine out. And its the same brake that's in the truck that had the donor engine. A Babcock 2 piece. Slides over the input shaft of the trans and mates up to that nose cone/plate unit with springs on the trans side, then up to the flat side of the TO bearing. It's almost as if there is no clutch brake action taking place. If it was a automobile with a manual trans, it would be like pressing the clutch down just barely, enough to not stall the engine when the trans is in gear, but not enough to easily slide the shifter in or out of gear.

Also the cable was replaced when I installed the engine/clutch and reassembled everything. It's a Mack sourced cable for the truck VIN that had the same specs as the old cable.

Thanks for clarifying what term is for what when it comes to adjusting. I adjusted the 5/8 adjusting bolt (w/pedal depressed with a 2x4) to the point of having more then 3'' free travel in the pedal to almost no free travel. Equating to +/- 1/2'' gap between the TO bearing and the clutch brake. I use a piece of 1/2'' round stock bent in such a way to fit around the release fork to make that measurement. I also adjusted the external linkage rod. Neither of which made a noticeable difference. I have messed with both adjustments lots over the past couple days, but messed with them again during this test with the wheels off the ground so I can run the driveline.

The 4 rubber mounts on the bellhousing/trans area are in great shape. I think they were replaced not too long ago by a previous owner. The front mount "seems" fine...not really too sure what to look for there. The shift levers do rock a fair bit. Actually more then my other 3 six speed trucks do

Ok so, I blocked up the rear of the truck, plumbed in my service brake lines. With the engine running and the transmission in gear and spinning the driveline, I can apply brakes until the truck wants to stall (no clutch slippage occurring), then while maintaining steady pressure on the brake treadle, I step on the clutch and can stop the driveline. Then release the clutch and start it spinning again. So there is SOME disengagement however it's not fully disengaging. There is still some audible load on the engine as it still wanting to spin the driveline but I have the brakes applied. The instant I release the brakes the driveline is in full swing again. I rough housed it a bit on and off the brakes with the clutch 2/3 of the way depressed etc.... and im now pretty sure nothing is "seized" from sitting in a damp environment for a few months without use. Here are some pics with clutch applied, clutch released and linkage disconnected and pulled back in the last 2 pics to view the clutch brake. You can kind of see it in the last pic. The back side of the clutch brake (closest to the trans) has got some noticeable meat worn off of it, probably from me trying to get it working over the past couple days. I adjusted the quick adjust +/- a few times while doing this and no real difference in results. I don't know, I guess im pulling the damn transmission again......

I dont know. They appeared the same, but there might be discrepancies there.

Yes it's tight up against the brake when the pedal is depressed. Im pretty sure it would come out of gear with a quick blip of the throttle followed by pulling it out of gear, just that I didnt have room for that when I jumped into gear on me when I was messing with it so I had to pull the shutdown cable

Yes the machine shop did leave maybe 1% of the outer edge un machined due to there rigging not being able to bit that far or something. There was next to nothing for a lip, but lets hope thats causing my problem! Hayseed-Yes they are the same flywheels.

Tomorrow I might try blocking up the rear axle and run it thru some gears and jar it with the throttle a bit

Im wondering now if one of the dogs got out of whack when installing the center disk of the clutch. there was no slop in there had to give it a push to get the disk on.

The engine is a 235 and trans is a 107 six speed in both trucks. Same flywheels, different model trucks. Both had mechanical clutch linkages with a cable from the pedal. but slightly different linkage setup at the bellhousing, so that's a difference. The new clutch looked the same as the clutch that was in it, the numbers off the old clutch were cross referenced to the new clutch. I didn't mess with the dogs. What tool is there to align them? Yes the clutch brake is on the trans input shaft. It's a Babcock 2 piece. Same that was in there. Ya so the main symptom here, just so I stay clear in my ramblings; is the clutch will not disengage while the engine is running, to allow the transmission to be placed in gear. I installed the clutch on the flywheel/engine while the engine was on the ground being overhauled. It installed into the truck pretty flawlessly. Anti rattle "shims" were installed as per instructions in the clutch kit. I was new to those but I don't think they would be causing my grief. Im thinking the issue must be internal. Im hoping its just a sticking clutch disk that I can free up somehow, I just can't really drive it at the moment to free it up buy rough housing it a bit. I will take a pic and post it here so there can be a visual.

The engine starts and runs no problem. With the engine running, when I depress the clutch to the floor to wait a couple seconds for the clutch brake to do it's thing, I cannot get it into gear, it just grinds as if im trying to stab it into gear without pressing the clutch in. I can wait a long time with my foot to the floor, and still no engagement, it just wants to grind.