Barrett,
>From vast experience - chances are you have bad valves. The best way that I
found to check this to be sure exactly what it is, is to do a "leak down
test". I know that Snap-on makes this tester so I'll assume that others do,
too. The "wet test" that you did is a good indication that it is the
valves, especially if you haven't tinkered with the engine for a while to
mess up the cam or cam "alignment" in any way. I think that the fact that
the compression was so close wet or dry shows this.
This test involves putting air into the cylinder through the spark plug hole
and listening to how or where it exits. For example, if the exhaust valves
are bad (after closing the intake and exhaust valves by loosening the valve
adjusting screws and/or moving the crank to the position that closes these
valves) then you will here the air coming from the tail pipe. If the intake
are bad, then the air can be heard coming from the carb. If the rings are
bad, listening to the end of the piece of surgical tubing put into the
dipstick hole will allow you to hear the air escaping.
Keep in touch. I am happy to help more if you need.
Michael Lubitz
1946 Chevy 3/4 ton, stock
1948 Chevrolet 3100, hot rod
Austin, Texas
----- Original Message -----
From: "Barrett Revis" <snappydog@jackass.net>
To: <oletrucks@autox.team.net>
Sent: Saturday, May 05, 2001 11:08 PM
Subject: [oletrucks] 216 Compression
> Beautiful spring day and all, I thought I'd tune up the old beast
> ('53 panel w/ 216 babbit beater). The shop manual says to do a
> compression test first.
>
> Okay.
>
> I warmed up the engine, pulled all the plugs, opened up the throttle
> all the way, and dry tested each of the cylinders.
> I then one-at-a-time squirted 10cc of motor oil into and re-tested
> each of the cylinders.
>
> The results are as follows:
>
> Cyl: Dry: Wet:
> -----------------------
> #1 100 100
> #2 100 120
> #3 55 65
> #4 75 80
> #5 100 120
> #6 75 85
>
> (ominous music plays here)
> Doesn't look very promising to me.
>
> The shop manual merely says:
> "Compression on all cylinders should be 110 pounds or better and all
> cylinders should read alike within 5 to 10 pounds for satisfactory
> engine performance."
>
> Can anyone offer any special insight on what these readings mean, or
> advice on what I should do to correct this situation?
>
>
> Barrett Revis
> Sparks, NV
>
> '53 3105
> '48 3105
>
>
>
> -- Barrett Revis, snappydog@jackass.net on 05/05/2001
> oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
oletrucks is devoted to Chevy and GM trucks built between 1941 and 1959
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