Transaxle problems...

[AllisPhreak 0]

Yep, another transmission problem. I have a Allis-Chalmers 616 "special" with a 5-speed Peerless 801-019a trans-axle. (This is identical to the Simplicity 5116). I am not sure whether the problem is stripped gears that require a rebuild, or a simple adjustment (hopefully) that would resolve this problem. Here's a description of the problem : Usually, all forward gears work flawlessly. Can shift though-out the range. Then I try to put the tractor in reverse. That's when the problems begin. It keeps trying to pop out of reverse (or perhaps slipping ?). I wiggle the shift lever, and sometimes reverse will re-engage, but will always slip again. Now, I try to put it back into one of the forward gears, and lever will refuse to go beyond 1st gear. Not only that, neutral is now a forward gear for some reason. Now, by working the shift lever, I am eventually able to get all forward gears operating properly. Lo and behold, I have a neutral again. Also, now when I shift back into reverse, although occasionally it will still pop out of reverse, if I hold the shift lever as far over as it will go, reverse will operate almost normally. Is this symptomatic of worn drive gears, or some sort of faulty shifting mechanism inside the trans-axle ?

[UCD 14]

Sounds to me like warn or bent shifting fork and or collar.

[AllisPhreak 0]

Well, the old tranny finally gave up the ghost yesterday. I was out in the back '40 hauling a loaded trailer full of brush up a short hill when --- I stopped moving forwards and I started rolling backwards down the hill ! Not good at all. None of the gears would then work, not the 5 forward gears, not the reverse gear. It would jerk forward slightly like it wanted to engage, but no dice. Well, time to go where no man has gone before (well, at least not THIS man !). Time for me to delve into the guts of a trans-axle for the first time. Could I do it ? Remains to be seen. Luckily, I bought from Mark-AC a busted up tranny from his old 5116 that he parted out (Thanks Mark !). Let's see if I can salvage a few parts. I found the solution to the first of my issues with the tranny slipping out of gear/difficulty engaging ! What do you think ? Might this be the problem ? :

The lower shift link appears to be worn badly, "wallered out" if you will. Good thing I had that tranny from Mark, huh ? As grateful as I am that that problem appears to be resolved, it does not explain why the trans-axle would engage in gear, but not move in any direction. Let's clean up some of that old grease, and see what we got. AHHHHH, there it is ! :

Not a single tooth left on the marked gear ! NOT ONE ! What I'm wondering is how it moved in any direction at ALL ! Ok, let's open up Mark's old tranny and see if there is something salvageable. By George, I'm in luck !

The exact gear I need appears to be in pristine condition, by the looks of it. What luck, yes ? The other two marked gears seem to be chewed up pretty good, but the one I need is in perfect condition. Plus, I salvaged the brake disk from Mark's tranny that will replace the paper-thin one currently on the tranny. Not bad for $5, hey ? Ok, now that I'm done tooting my own horn, perhaps I can get a bit of advice from my fellow tractor fanatics. At the risk of beating a dead horse, I repeat that this is my very first transmission rebuild. I realize I also need to replace seals & bearings, but which ones ? All of them ? Do I really need dis-assemble the trans-axle completely and replace every single O-Ring, seal, and bearing ? Everything else within the trans-axle seems to be in relatively good condition. Lastly, what's a good affordable solvent that will strip the old grease from all the parts ? I checked with my local NAPA, and I just cannot see spending $48 for a gallon of solvent used for part-washers. Nor can I see picking up 15 cans of carb cleaner to clean this trans-axle. I tried using gasoline, not a chance. Then I tried a bit of paint thinner. Again, no go. What say you ?

[MarksA-C 93]

Glad to see something good was in that tranny. If you ever need any other parts, I probably have 3 extras for your style tractor.d:) Mark-

[AllisPhreak 0]

Thanks, Mark ! Other than those two gears in the lower picture that are moderately worn, everything else inside is in reasonably good condition. I just hope I have the skills necessary to rebuild this thing. Thanks again, Mark !

[carbuff713 0]

You can do it. Take your time, setup a nice place to work, carefully follow the parts breakdown. It will feel great when you get it working again.

[Roy 0]

"I tried using gasoline, not a chance. Then I tried a bit of paint thinner. Again, no go." Varsol, mineral spirits, acetone, or lacquer thinner will work. All about $8 a gallon. The gasoline (although dangerous to use) or paint thinner should have worked; not sure why they didn't. Worn bearings and worn/leaky seals should be replaced. It is a matter of inspection and experience to decide whether, or not, they should be replaced. O-rings are cheap but won't need replacing unless leaking or damaged upon disassembly. Best method is to go through the whole transmission and replace any worn parts. Quick dirty way, if everything else is OK, is to only replace those parts it was necessary to disassemble to make the repair. Good luck,

[Al 6]

Hi, That grease is bentonite (a type of clay) based. Clean it all out and get all of the metal shavings out. Be sure to check and probably replace the shift keys while it is apart. If you have 4 slots in the shaft, put 4 shift keys in it and it will be twice as strong. DO NOT GET THE WASHERS BETWEEN THE GEARS TURNED AROUND. THE BEVELS ON THE INSIDE OF THE WASHERS HAVE TO GO IN THE RIGHT WAY. Tecumseh has this grease in a big plastic tube. Al Eden

[AllisPhreak 0]

Ok, all back together, running like a top. (Still very occasionally pops out of reverse, but I can live with it). I have a question. Whilst putting the tractor back together, I realized the the left rear wheel did not have a key in the keyway. (nor was there ever one there, as it was coated with rust pretty good. I had noticed prior to the rebuild that when stuck in the snow or plowing, only one wheel would spin and dig in. My question is, could the missing locking key on the shaft been responsible for the transmission failing ? I was wondering if the uneven torque on the rear wheels could have 'racked' the gears in the trans-axle, causing teeth to break off ?