This morning I bestirred myself from the comfort of my chambers and hied myself out to the driveway, where I began the latest endeavor in the diagnostic procedures intended to enlighten me as to the mechanical ailment which besets my jalopy.
Compression check. #1: 165. #2: 180. #3: 180. #4: 150.
...number four is out of whack? #1 is within 9% of #2 and #3; so #4 is the problem?
So I did the leakdown test on #4, and I can clearly hear air escaping past the piston and into the crankcase. How much is normal, I don't know, because I banged the shit out of one of my knuckles--knocking off a chunk of skin and bleeding a lot--trying to move the crankshaft with a wrench and I didn't feel like doing that again. It may be normal, it may not be.
Besides that, though, when I pulled the spark plugs? All of them--all of them--have a coating of greasy black carbon on them.
If something went wrong with #4--oh, for giggles let's say I broke the piston rings when I installed it--I would expect #4 to have excess carbon on its plug; it would make sense. But not all four. So the engine is running pig rich, reason unknown.
And even though #4 is more than 10% off the other cylinders (about 15%) it's still clearly making decent compression, so it ought to be firing. Right?
So I'm going to have to think about this one, a lot, and I'm probably going to have to enlist some help, because this shit doesn't make sense and I'm pretty much at the end of my rope.
