...and a mechanic too

After clearing a forest of weeds from down by the road I went to get the little garden tractor to help move the debris.  It started OK, but it sounded funny.  I drove it from the shed down to the garage and tried to diagnose the problem.

I took off one spark plug wire and it died immediately; it's a two cylinder so it should have kept running, just very rough, so I started checking the other side.  Everything seemed to be in order, so I took off the spark plug wire and started it, and it started and ran exactly the same as before.  So I put the spark plug wire back on (while it was running) - not exactly the best idea, since it feels a little like the electric fence when you do that, but it did confirm that the cylinder wasn't firing and that the spark was definitely strong.

Since I don't know much about small engines (or big ones for that matter), I started my normal mode of diagnostics.  Take off likely looking things until something happens.  I got lucky this time.  I took of a dish shaped cover and found the overhead valve compartment.  Inside I found this:

It's a pushrod and it's supposed to be straight.  I quickly noticed that it's not.  If you noticed that too, then you're as good a mechanic as I am, I suppose.

According to one web site, this model engine (Briggs and Stratton Intek V-Twin, 26 HP) has a known problem with valves.  If the fins get blocked and the heat can't get out of the cylinder, the aluminum head expands more than the valve guide sleeve and the guide sleeve slides out of the head, cocks and jams the valve stem.  See if you can guess which cylinder I was having trouble with.

If you said, "the one on the left with the mouse nest on it?" then you get a gold star.  I've ordered two new push rods, a new guide sleeve and a dozen mouse traps; now I just need to figure out how to get the valve spring off the stem.

Oh, all that stuff down by the street that I went to get the tractor for?  My beautiful Farm Wife dragged it across the road, bit by bit, and tossed it over the hill while I was learning about engines.  Later I used the Jeep and a chain to drag the big branches away.