I had a Fat-Allis HD31 in my fleet in Kentucky. Most of the operators didn't like it, but there is always one skinner that takes a shine to the oddball machine seems like.
Like all the rest of our machines, this one had not been taken very good care of. Most of the cab glass was gone and the cab itself was real loose. It shook like crazy, and the one operator of this machine spit tobacco juice everywhere inside the cab. He was a real pig. One of the reasons why the machine was in poor shape was the mechanics hated to get near it.
But we steam cleaned it and took the cab apart. Tightened everything up, put new doors and glass in it, fixed the A/C and heater, and reinstalled the cab on the tractor. Put a new undercarriage on, fixed all the leaks and had the engine tuned.
It would stay with the D9H's just fine and was maybe a bit faster as it was more powerful. The D9L's, when they ran, out worked it easily.
The engine failed one day, put a rod through the block. So we bought a crate engine and stuck in it. Only the Cummins boys forgot to tighten the oil pan quick change hose fitting. It came loose and the new engine burned right up. Cost Cummins a bundle to put another brand new engine in it. We wouldn't let them rebuild the damaged one. You can be sure they double and triple checked all the hose connections when that last engine went in.
I worked on HD41's in Florida shortly after I got out of college. The dealer I worked for had several in the state. One of our biggest customers was the City of Surfside down towards Miami. They had a huge landfill there with three of the 41's in it pushing trash around. They had a big fleet of AC scrapers too.
The 41's caught fire often from trash getting near the turbo's and exhaust manifolds. This usually burned up the wiring on the firewalls and in some cases the instrument panels. In one instance the engine was left running and a hose burnt in half near the engine compartment. The entire machine burned and we had to bring it into the shop for an overhaul. It looked hopeless, but in three months a near new tractor emerged. At least the fire got rid of all the smelly trash piled up in the pans and guards.
One of the fat old mechanics we had was assigned to the dump and these three machines. He always requested some skinny little guy from the shop to go with him when the machines had tranny trouble. He would direct the skinny guy down under the seat to hook up test gauges to the tranny and torque converter. One day the skinny guy wasn't in so my boss sent me instead. Sure enough I got sent into the hole. Oh my, you never smelled anything so bad in your life. Lots of garbage got squeezed into the belly guards under the tranny and engine and in the heat, well, use your imagination, than times that by ten.
It was late in the day when we arrived and I assumed we would test and get the hell out and return the next day to replace what turned out to be a badly hurt transmission, but no, the field mechanic and my boss were in a big hurry to get this tractor back up, so we started taking the trans out, which meant taking the cab back, getting the flooring out and removing the trans from the top. They were pretty good sized and the little field trucks couldn't lift them. For that we had a F750 with a 12 ton boom at the shop.
We finished up long before the boom truck showed up with the new trans, and I went to sleep curled up under the tranny on the belly guard. Man I was tired, course, I did most of the work too, and it was hot. But at least the mosquitoes left me alone in there. They concentrated on the field truck cab where the mechanic was holed up. He wouldn't roll the windows up cause he smelled worse than the garbage dump most of the time. Had a complete aversion to soap and water you see. So getting in the cab with him was not an option.
Boom truck showed up around ten that evening and we three worked our butts off the rest of the night swapping things out and getting the tractor buttoned up. I went home with the boom truck operator while the mechanic stayed with the tractor and waited for the dump lube truck to show up with fluids and coolant. When we got to the shop the boss sent us home (he was pinching his nose at the same time) and he told us to take the day off. My ole lady wouldn't let me in the apartment till I took off all my clothes and piled them in the garbage can beside the door. Then I took a long shower, but I still smelled like garbage for three days.
I told my boss that if he ever sent me back out to the dump or anywhere with that mechanic, I'd kill him before leaving the shop. I do think he believed me for he never did.
A lot of the factory guys came by our dealership (we were the biggest in the US) and they were sure unhappy when Fiat bought into the company. The owners of the dealership weren't happy about it either. Kelly Tractor (Miami Cat house) was really struggling at the time and there was some talk about the owners of our dealership buying them, but apparently Cat wouldn't even talk about it. We dealt in Poclain too, and between Allis-Chalmers and Poclain, the dealership kicked Cats butt severely in the early 70's in south Florida. The recession and the gas shortage in 74 really hurt everyone in Florida, we didn't sell a thing brand new for six months. I had by then developed a healthy dislike to south Florida and my wife and I decided to get out. We weren't the first to leave nor the last.
of Allis-Chalmers . From its' beginnings , to the end. Author Norm Swinford 
