Sunday, October 12, 2008

Evolution

I've had my Gravely/Ransomes home-built leaf-cleaning rig for going on three years, and used it two seasons thus far. And as I mentioned last time, keeping it running and functioning has been something of an adventure in old equipment.

I chose the Gravely because it has gear drive, rather than belt drive. I needed a tractor that had the ability to climb hills towing several hundred pounds of leaf mulch, trailer and leaf vacuum, and a belt drive seemed suspect in that regard. But it still has a belt to drive the mower. The first year, the mower deck belt broke, and since the leaves are swept up and given an initial mulching by the mower deck, it obviously needed to be replaced. Figuring out the serpentine path of a mower belt is always a joy, and ever since I replaced it, the new one smells like burning rubber whenever the PTO is engaged. I'm expecting the belt to break again, but I'm hoping the belt will eventually just burn off whatever compounds are in it that make it smell, and that when it's done so it will still be intact. In any case, I can't figure out why it's overheating, if that's what it's doing.

The tractor has otherwise been pretty easy to deal with. The starter switch is a little touchy, and the throttle cable pops off the throttle lever on a regular basis up behind the dashboard (which is maddening, let me tell you). But that's pretty much it. Actually, the latter is why the hood is missing from the front of the tractor in the picture above -- it's much easier to get at the throttle cable that way. Old Gravelys also leak, so I store it without any oil in the transmission case, because the right side axle seal will otherwise let a bunch of oil escape during winter storage.

Oh! And I siezed both engines last year. That's right -- both the tractor's engine and the truck loader's engine. On the same afternoon. That was not a good day.

The leaf vacuum went two seasons without me thinking to check or change the oil or air filter. Yeah, I know -- not smart. There was oil in it when it siezed last year, but it was a lot more like tar than oil. Not good. It never un-siezed -- that engine was well and truly toast. This happened maybe an hour after the tractor's engine locked up. That one ran dry of oil because the fuel pump leaked the stuff like a single-hulled tanker. Or a Gravely. I let it cool down, put oil in it, and it ran again, but not well.

Clearly I was distracted last year -- distracted for the same reasons that find me living in apartment for now, I suppose. Normally I'd expect siezing an engine to be enough of a wake-up call to get me to actually check on everything else. No such luck last year.

Anyway, I finished the leaves by hand (I was almost done anyway), and started looking for solutions to those problems as soon as the snow melted this past Spring.

The dead 7HP Kawasaki came off the vacuum over the winter, and in June was replaced by an 8HP Briggs & Stratton from a broken (Italian) BCS tractor I picked up in March or so. It was a pretty sweet deal. The seller didn't seem to know what that tractor was, so he'd posted the tractor on eBay essentially as a functioning 8HP B&S engine with a disposal problem bolted to it. A $115 bid sealed the deal (sweet!), and the engine fired right away when I picked it up. I took the engine off, and found it had the right shaft diameter for the truck loader (which was an educated guess, but still lucky), and as I put it on the Ransomes, I further found it had the right dimensions for all the bolt holes on the Ransomes' housings to line up properly. The muffler's a bit close to the frame, but I did what I could with the little shield that directs the flow, and it shouldn't be a big deal as long as I watch where I put my hands

I posted the engine-less (and now properly identified) BCS tractor on eBay this Summer and got about $115 for it. So I essentially got a free replacement engine. That's a break you don't get very often, and I promise to take care of this one!

You'll remember that the rider still ran last year, but not all that well. I figured I could limp it through this season rather than fixing it. And I figured that if I couldn't, I'd just find a used Gravely-spec Kohler and bolt that on in place of the Onan, for which parts are much harder to come by these days. Either way, I had to get the oil leak under control, as it wasn't doing the tractor, the environment or me any good. So last weekend, I took some time to fix the oil leak.

It appears to have been caused by two things. First, the pivot pin for the armature had drifted out of place -- all the way out of one side of the casting, and the open hole made for a fine oil drain. And second it had a bent mounting flange. The casting was either flawed all along, or had bowed over time. I'm not sure how likely the latter is, but the thick rubber spacer between the pump and block might not have provided for a sufficiently stable and flat surface to torque down the casting against.

I removed the pump and took it over to Waverly Tool over in Framingham. Following the advice of a very helpful guy in the parts department (whose name I didn't get, unfortunately), I took the pump's armature out (which was actually when I noticed the pin was out of place), then used some emory cloth sitting on a flat countertop as a grinding surface to even out the flange. It took maybe a half hour to sand it flat and clean the grit out of it. Then, to make sure it didn't warp again, I fabricated some crude spacers from aluminum stock to replace the rubber spacer. I put the pin back in properly, and bought three fresh gaskets (to sit between the engine block and the first spacer, between the two spacers and between the second spacer and the fuel pump).

I then fired up the rider after a year's dry storage and discovered that the plug wire was arcing (it was visible in the darkness of the barn's basement). A little electrical tape solved that problem, and... Voila! Much to my delight, the engine runs great and now seems no worse for wear from its sieze-up. No burning oil, no undue noises and plenty of power. And the pump has no leaks, even after 20 minutes of high RPM running.

For this season I've also replaced the old rubberized cloth and wire hose (which had been burned through by the muffler in a couple of places) with a new polyethylene hose. And I'm going to rig up a J-shaped support bracket from iron pipe to hold it up and out of the way of the exhaust. That one will sit on the back of the tractor, behind the seat on the engine cover. Then I'll put another support on the trailer's tongue. I was first thinking I just needed something to keep the hose away from the muffler, but I don't think that's going to be foolproof, so I'll make some more substantial supports instead. The new hose is clear, so I'll be able to see clogs more easily (sticks tend to clog things up), and it's sturdy, so it shouldn't kink up as much.

This weekend I have my girls with me, so I'm going to put the rig together next weekend and make the first sweep of the lawn. I'm sure there will be teething problems with this new configuration, but I'm looking forward to playing with my toys.

All for now,

J

No comments: