"If you seek Truth, you will not seek to gain a victory by every possible means. And when you have found Truth, you need not fear being defeated." - Epictetus
About nine years ago, I bought a compact 4x4 tractor to clear snow from the driveway.
The little tractor wasn't really up to the job. We have a pretty big driveway, and when the snow fell hard, it was tough to keep up with it. Sometimes, by the time I was finished clearing, I'd have to start over again, because the process was so slow.
The bucket is only 4 ft across, and once it fills with snow, additional snow just falls off to either side. It's not like the plow, where you can angle it and push snow off to the shoulder. It was awful having to go back and scoop slop that fell off each side - every single pass. It was impossible move the snow where I wanted to, quickly.
The tractor moves slowly, and it's a manual, so there is a lot of shifting involved. The bucket required constant adjustment to avoid digging into the driveway. The entire time it would usually be snowing, so I got soaking wet, with snow in my face, usually in the dark. Not a great way to move snow. Let me re-state that - It was a harsh, demoralizing and difficult way to move snow.
The tractor wasn't too reliable anyway. The guy who sold it to me definitely saw me coming. A word to the wise: Don't buy used farm equipment. By the time a farmer is finished with it, it's held together with bailing wire and bubble gum, and it's ready for the crusher.
After a couple of breakdown-filled and miserable winters, I replaced the tractor with a Meyer snow plow. This attaches to the truck, and it's been awesome. The plow is worth every dime - I can clear the driveway in two quick passes, while I listen to music, enjoy a heated cab, and stay out of the weather.
Back to the tractor though. The Yanmar is a Model 155D (D for diesel), with 15 whopping horsepower! Below is the engine nameplate.
The tractor is old and unsafe by modern standards. It has no PTO guard, and it has no rollover protection. As mentioned before, it's a manual, so that's a pain in the butt too. During the few operating hours I've put on it, it's had a number of problems, which I will relate below:
- It cracked one arm of the loader. This was really annoying, because the loader is also the reservoir for hydraulic fluid. I had to drain out the fluid and haul the loader down to a qualified welder. He in turn had to purge the inside with nitrogen so that the residual oil film would not ignite as he repaired it. Who knows how much oil and soot got into the weld from inside the loader arm???
- On different occasions it blew two different hydraulic hoses - spraying me in the face once. The tractor was out of commission until I could have new ones made up.
- The loader mounting bolts fell out while I was plowing. But first they came loose and fcked up the threads in the engine block. I had to re-drill and re-tap those holes for bigger bolts.
- The shifter for the gearbox started flopping around one day. Once I got inside, found that a roll pin was cracked in two, but had been repaired with a very tiny roll pin inside of the broken one. What a retarded jury-rig! Just get a new roll pin! I drilled the hole out bigger and put in a large roll pin.
- The last time the tractor failed, I was pretty certain that the engine had seized on me. I was shoving really hard on a pile of compacted dirt with the bucket. The engine suddenly stopped and the entire tractor rocked as the engine locked up. The starter wouldn't even make the engine twitch. I figured the tractor was finally beyond repair at that point.
After the engine quit on me in the middle of that job, I got disgusted and pushed the tractor out behind the shop and covered it with a tarp for a couple of years. Last autumn, I moved it into the shop, hoping to repair it over the winter - but I never managed to get it done. The husky dog is high maintenance, and I don't get much done on those rare days I'm home, unless someone else is home to keep watch on the dog. She has a tendency to gnaw on the dachshund when nobody is watching.
I recently drained the engine oil and removed the bottom oil pan on the tractor. I wanted to inspect for damage and try to figure out what was wrong inside the engine. I expected to find all kinds of damage - metal bits in the oil, gouging of the cylinders, maybe a broken piston rod. Amazingly, there was nothing at all wrong with the engine!!!
Later, as I was moving the tractor around in the shop, I noticed that while turning the steering wheel, the tractor kinked at the interface between the engine and bell housing for the clutch. The tractor had a loose joint in the middle. I've never worked on a tractor before, and it turns out it's not like a car at all. With a car, your unbolt the transmission and drop it out the bottom. With this tractor, you remove some interference ,and then you split the tractor in half. The transmission and bell housing is part of the tractor's structure - which makes this tractor a bit flimsy, in my opinion.
I got the biggest laugh when I uncoupled the front and rear halves of the tractor though. Half a dozen bolts fell out of the clutch housing onto the floor as the tractor came apart. These bolts hold the tractor together, and had come loose inside the clutch housing. This is what allowed the front and rear of the tractor to become misaligned. This alignment issue is what caused the sudden drag on the engine and stopped it.
At this point, I'm guessing that the tractor got a quick clutch replacement shortly before I bought it, and the bolts didn't get tightened well enough. They fell out over time as I worked the tractor hard, and eventually enough fell out that the plate warped and flexed, allowing the tractor to bend enough to lock the engine up.
First I had to flatten out the plate that the bell housing attaches to. This plate attaches to the back of the engine, and the clutch bell housing bolts to the outside of it. It took a while, moving between the press and the bench vise to get it reasonably flat. I had to remove the mounting studs for the starter motor before I could begin flattening out the plate.
The misalignment between the front and rear halves of the tractor didn't do the drive-train any favors. Below is the engine flywheel, with rust markings where the clutch plate has been contacting it for the last few years. The rust can be removed easily enough. However, at the center is the pilot bushing, and it's probably seen better days. The bushing is what the transmission input shaft slides into. A bit of damage there. Fortunately this bushing only costs $6 to replace.
I bought some slightly longer replacement bolts and installed some lock washers to attach the plate to the engine. Hopefully these won't come loose next time.
The throw-out bearing (also known as a clutch release bearing) feels a bit crunchy, so I'm replacing that while I've got the tractor split in half. Replacement cost for that is about $30. Old one below. Considering how much rust was in the clutch region, it's not surprising this is also rusted.
Below: I'll have to press the old bearing off the carrier once the new one arrives.
The clutch plate is rusty, but has a lot of material remaining on it. Surface corrosion, but it looks pretty fresh wear and tear wise.
The clutch cover has a lot of surface rust, but is also sound. It'll clean up.
Below: Engine flywheel (transmission side) with rust marks from the clutch plate. The damage bushing has been pressed out.
Below: Other side of the flywheel - engine side. Teeth for the starter are in pretty good shape.
Teeth on the flywheel up close.
Lastly, I noticed that one of the front rims is badly cracked. This thing has spider-webs throughout, but the other side is fine. Weird. Replacement cost is about $100. It's a tiny rim - 12" x 6". It probably broke because this tractor is too tiny to handle the stress of a front loader. Maybe it's a farmer thing to make equipment do stuff it was never intended for?
I had to run the oil pan under the wire wheel to remove the old gasket. It was really stuck. Not sure how I'm going to remove the old gasket from the bottom of the engine.
I made up a new gasket for the oil pan, because it's cheaper and easier than locating one and having it shipped.
Below: The PTO (Power Take Off) shaft. No guard. These have killed and maimed a lot of people.
So far the project is nowhere near as bad (or expensive!) as I thought it was going to be. I figured it would be an engine overhaul, with new pistons, new engine bearings, and maybe an over-bore. This is nothing!
Updates will be forthcoming as parts arrive and I get days off to replace the parts.
UPDATE: 11-19-21
New rim. The tire is now mounted on this rim.
The other parts arrived, and I've begun re-assembly. The new clutch release (aka throw-out) bearing has been pressed onto the carrier, below:
Below, after cleaning the flywheel clutch side of rust and bushing dust, I pressed in the new bushing.
I removed the cracked rim and tire from the front half of the tractor, and discovered why the rim had cracked in the first place. There is a huge degree of play between the steering linkage and the shaft that turns the front wheel. Therefore the wheel was canted outward or inward and side-loading the sheet metal that the wheel is made from . It cracked where all the holes hold it in place. I need to find the source of the slop in the linkage. There is a bolt that seems loose in this image, and maybe that's the source of the problem. Hopefully that's all it is.
UPDATE: Progress report here
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