Meet Frankentractor:
(Pre-engine swap)
Frankentractor started life as a 1953 Allis Chalmers WD45, a pretty capable farm tractor for the period. From the factory, it had the wide front end and a 226ci inline 4 cylinder gas engine rated at 45hp at the belt. Somewhere along it's life span, someone added a Henry TS-1 front end loader with dedicated hydraulic pump, and a monstrosity of a home-built cab.
We picked this thing up locally because I was looking for a loader machine to do random work around the yard, and the price was right.
(My wife, running down a brick bbq the previous house owners built in the most inconvenient place possible - glorious moment)
We used it as-is for quite a while, but since day one, the rear crank seal had some degree of leakage, and the fluid leaking out was an alarming shade of "milkshake". The seller had mentioned he had a friend who had done a reseal on the engine to tighten things up, but the rear crank seal was this two piece felt affair that was notorious for being finicky (which I learned more about later on). I chalked it up to rainwater getting into the oil somehow, and carried on with regular oil changes and it worked, for a while.
Over the course of a few years, the leakage got worse and worse and I finally decided to attempt a fix. At first I thought it was the rear section of the oil pan leaking, so I replaced the four piece pan seal, to no avail. I decided to do the rear main seal, and figured while I was pulling the engine, I'd do a full teardown, overhaul, and paint it. New rings, seals, really spruce it up.
The factory engine is a wet-sleeve design, which means the block has upper and lower webs that hold removeable cylinder liners. These webs are prone to cracking at the top, right in between the liners. The head gasket at the top keeps the coolant where it belongs so it's not a big issue. Cracking at the bottom, however, is more of an issue. And this one had cracked at some point, and been repaired, poorly.
The lower web had some sort of weld repair done to try and pin it back together. The problem was the inner bore was not cleaned up well at all and was significantly out-of-round, which wasn't allowing the sleeve o-ring to seal, leaking coolant into the oil, resulting in:
So, I resealed the engine anyway, painted it, reinstalled the sleeves, put a bunch of block filler in it to permanently seal the sleeves and keep them from leaking and put it back in the tractor.
And after all that, the thing still leaked milkshake. So that was it, I was done. I was ready to sell it or scrap it. My wife talked some sense into me and the tractor sat for a while.
So then, remembered that small block Chevy motors are good for just about everything, and got to wondering if I could get one in there. Took some measurements, and while the tractor frame and loader rails would pose some challenges...it might work.
Yep, looks perfect.
My father in law is a hobby machinist, and we were able to get him on board with this project as far as making up some adapters for the engine and flywheel to mate the SBC block with the factory tractor bellhousing. This would allow me to use the SBC engine, and keep the tractor's stock flywheel, starter, and clutch. This was challenging, because the me and the tractor are on the east coast, and my in-laws live on the west coast, so we were only going to get one shot at this. So, lots of pictures, measuring and facetime later, we had the adapters. Thanks Alex!!
Meanwhile, it was becoming apparent that the tractor was going to require a little more surgery than I initially anticipated. This is a standard Gen I Chevy 350 that came out of a 1984 pickup truck and came with a Rochester Quadrajet carb, which I rebuilt prior to final installation.
I ended up cutting out the insides of the C-channel frame rails and adding additional reinforcement on the outside, effectively turning them inside-out in the center.
This also required some re-routing of the loader hydraulic lines and the steering shaft.
So, then we had some adapters.
It fits!
My father in law also fabbed up the motor mounts for me, to hang the motor in the frame. The cutout in the plate in front of the motor is obviously "custom", the stock engine had a crank-mounted hydraulic pump fitted for the loader hydraulics. The cutout was needed for clearance to get the pump fitted.
I tried several different header/manifold styles for the motor placement - block hugger headers, stock rams horn manifolds, and a set of silverado rear-exit manifolds. None of them provided the clearance needed to get the exhaust pipes past the loader frame, so I opted for custom headers. Father-in-law had a set of manifold plates, so I ground out the old pipes and welded in some new stubs, and attached a collector.
I later added a tall stack after the mufflers with turnouts that exit above the cab.
After everything had the final test fit, the motor came out one more time for paint - Persian Orange #1, the original stock color.
Here you can see the flywheel adapter. The thickness was calculated to put the ring gear in the same place as it would be on the stock crank to ensure proper starter engagement, accounting for the different offset of the Chevy crank from the block and the thickness of the engine adapter.
Engine is going in...big thanks to my buddy Don for loaning me his engine hoist for...like a year.
The stock radiator needed to move forward about 6", mostly to clear the hydraulic pump. I fabbed a custom alternator bracket and used an electric water pump and electric radiator fan to leave more room on the front of the engine. The original radiator is not really up to the task of cooling the V8. Even with the fan running, it runs at about 220-230 degrees in the summer, and the stock cap is only a 4lb cap so it boils over pretty easily. Eventually I'd like to upgrade to a full aluminum radiator - the rad from a 64-66 Mustang is pretty close in size, so I'll probably get one of those and fab up the brackets needed to hold it in place.
So at the end of the day, it runs and I again have a working tractor. One improvement this setup would definitely benefit from would be a mechanical governor. I keep the RPMs under about 2000, because I'm not sure how much abuse the stock flywheel will handle, and it will bog down under load when I'm operating the loader. A governor would save me from monkeying with the throttle while trying to manage the loader controls all with the same hand. I also still need to stretch the hood 8" so it can sit in its normal position on top of the radiator and gas tank.
