The Stovebolt Site Forums The Shop Area Engine Shop Good, Good, Bad, Good, Bad, Bad

So there I am, with my new Compression Tester in hand, checking the 235 in my '44 ton-and-a-half firetruck. During the first outing this season, the truck starting stalling out on me, and during pumping, (before the pump broke!) the motor was spitting serious amounts of smoke from the valve cover vents.

I'm thinking the two are not the same problem. Forgetting the (assumed) fuel delivery problem for the moment, my readings on the compression were:

110
90
112
115
75
80

Note: I'm afraid to run the engine enough to warm it up, so this was done cold, AND I did NOT remove the airhorn and prop the throttle open. I DID remove all the spark plugs, well . . . except #2, which was stuck, until I broke the plug and pried it out with a breaker bar . . . I think it was cross-threaded, which could of course affect the compression reading. (and, which may in itself require the head to come off for repair! )

2, 5 & 6 all came up 10 psi after squirting a little Marvel Mystery Oil in the cylinders. I have never had the Valve cover off. Also, I had changed the oil just before the outing, I think modern 10W-30 went in, though I'd have to check.

I'm a rookie at this stuff, mostly, but I would like to rebuild the engine someday, anyway. I just thought I'd solicit advice before I start down that path . . .

Thanks,

-Michael