Hydraulic-ed

We haven't been using the lawn tractor much lately, mostly because it had four tires with various species of slow leaks and it's sort of a pain in the butt to have to drag the compressor or the hand pump out to air up yon tires every time you want to do something. So it sat, and sat, and sat, until finally I ordered four replacement tires from Northern Tool for it. So the tires duly arrived, and I duly went out to move the tractor to the carport so I could work on it on concrete rather than on dirt.

It wouldn't start. The starter would spin the engine to the compression stoke, then the starter would stall. I figured the battery was simply a little weak and wouldn't power the starter past the compression stroke, so I clapped the battery charger on it and proceeded to pull of the wheels where it sat. Now, I don't have a jack that really works on the tractor, so jacking it up consists mainly of grabbing one end of the tractor, grunting extravagantly, and trying to kick something like a milk crate or stool under the tractor while holding it aloft by brute strength. It works, sort of.

So I got the wheels off, and proceeded to try to get the tires off the rims. They'd had so much flat tire sealer pumped into them over the years the insides of the tires were full of an orange-green slime that coated everything, including me and my garage floor, with joyous abandon. It was so slippery I assumed it would help me get the tubeless tires off the rims, but no sale. It also made holding on to tools difficult. I broke the beads on one of the rims and managed to get the tire half-off, but I just couldn't get the inside bead off the outside rim. It was awful. There was no way to get any leverage on the thing at all with the tools I had, so I cut the bead with bolt cutters. Cheating, I know, but you do what you have to do.

Now it was time to put the new tire on the rim, which I'd scrubbed to rid it of the slimy green substance. I replaced the slimy green substance with a slimy blue substance, laundry detergent, used to try to lubricate the beads over the rims. I managed to get one tire on a rim, and even then only by kneeling on the tire with both knees and taking tiny eighth-inch bites with a screwdriver. This experience left me with double vision, a whooping cough, and bubbles of nitrogen in my bloodstream brought on by too much screaming, but worse was in store.

Now I couldn't get the beads to set. The tire had been squashed flattish for shipment and there was just no way of compressing it circumferentially enough to get the beads to come out far enough to seal on the rims. No way. I used my usual standby compression straps - a leather belt and a piece of strap - and nothing worked. Still, I wasn't about to admit defeat. I was about to start to cobble up a compression strap using my four-ton cable come-along when my wife said "Why don't I just take all this stuff down to Discount Tire and let them mount the tires?"

Why indeed? Frankly, I'd never even considered the possibility that Discount Tire would deal with lawn tractor tires. Even now I'm a little astonished that they not only claimed they could handle them, but that they did indeed handle them, and for four dollars per rim. By that afternoon the four shiny black tires were mounted on the rims, though I notice one of the rims still has a smear of greenish slime...

I mounted the rims on the tractor yesterday and decided I'd just drive it around to see how it felt. I turned the key, and the starter spun the engine through about a half a revolution, and again it stalled against the compression stroke. Now, remember that it had been on the charger all day, so I knew it wasn't a weak battery. So what was it? I backed the engine off by hand so the starter could get a "running start" at the compression stroke, and again it stalled. And it stalled hard, like there was something in the cylinder. Hmm. I tried to pull the engine past the compression stroke by hand, but no sale - it locked up hard at a certain point and simply wouldn't go any further.

Fiddling with this led me to ponder why the engine was making so many strange liquid gurgling and slurping sounds when the crankshaft was slowly revolved by hand. I took out the spark plug (thank heaven for small spark plug sockets) and there was a sudden gush of raw gasoline from the spark plug hole. And not a little raw gas either, we're talking a cup or so. Clearly the engine had hydraulicked on gasoline, meaning that there was so much gasoline in the cylinder that the piston couldn't complete its up-and-down motion because liquids can't be compressed. Engines normally hydraulic when they fill up with water, and are usually severely damaged in the process. But in this case, the engine had hydraulicked on gasoline, not water, and because it wasn't running when it happened, it wasn't damaged, it just wouldn't start.

So why would the engine be so full of gasoline? There was no time to think about it, because it was time to shower all the gasoline off my person so we could go to a Halloween party.

This morning I returned to the hunt. I had concluded that the most likely explanation was a carburetor malfunction, specifically something with the system that regulates the amount of gasoline in the float bowl. I had viddied that any one of several things might have happened. The float might have filled with gasoline and sunk. The float might have broken off the hinge arm. The needle might have gotten jammed in the needle valve throat. A flake of some wretched foreign material might have gotten wedged between the needle and the seat. All of these would result in the float valve remaining stuck open, which would allow gasoline to overflow the float bowl, trickle down the intake tube, and slowly pool in the cylinder.

So I took the carburetor off and took it apart and found nothing wrong. Nothing. Everything seemed to work. The needle sealed, the float floated, the hinge hinged. So I put it back together and let it sit for a minute with the fuel line hooked up, and presently it gushed fluids like a person chopping onions. Crap! So I took it apart again, and again, and finally did the old blow-in-the-fuel-inlet business while turning the carburetor upside down and right side up, and finally demonstrated that the needle sealed upside down and didn't seal right side up (the expected behavior). So I put it back together and this time it didn't gush fluids. I don't know why. I just went with it.

I put the engine back together and started it. It ran for about five seconds and died, and when I tried to start it again, it was hydraulicked again! Aaaagh! So I took the carburetor off again and found it, the cylinder, the intake tube and pretty much everything (including my shirt) soaked with a strange pale amber fluid that had some of the characteristics of gasoline, and some of the characteristics of motor oil.

You're probably ahead of me. As the thing sat with the carburetor slowly draining into the cylinder, the cylinder itself drained into the crankcase until the whole engine, cylinder and crankcase and all, filled up with gasoline. Instead of a crankcase filled with 1.6 quarts of oil, I had a crankcase filled with a couple of gallons of gasoline mixed with 1.6 quarts of oil, and any movement of the crankshaft caused the crankcase breather to pump this slimy fluid into the engine faster than the engine could get rid of it.

So I drained the engine, which took a long time, and put in new oil, and put the carburetor back on, and wiped as much of the mess off the engine as I could, and started the thing. It ran like a top, it did, just like brand new, so I decided to drive it around for a little while as a reward for all that work.

Consider that the engine was pretty much coated with that oil-and-gas mixture. Consider that the engine had pumped a pint or so of the oil-and-gas mixture into the muffler. Consider that hot oil smokes. Presently I looked like a steam locomotive, my tractor emitting such a thick cloud of smoke it actually left a shadow on the ground. There was smoke everywhere. I was afraid the neighbors were going to call the volunteer fire department, or perhaps report a crashed airplane, or that I would pass out under that incredible pall of smoke and simply die.

Eventually the oil burned off and the tractor stopped smoking, but wow was it a smoky mess for a while.

So that's been my weekend. Tires, a hydraulicked engine, and enough smoke to give Al Gore the cool shivers. And me? I'm covered with several layers of slime, including green tire sealer slime, amber oil-and-gas slime, and black carboniferous-smelling slime that rubs off my tools and probably dates back to the time I had to fix the blown head gasket in my truck.