Guys,
I need help. A while back I was having a problem with hard starting, etc.
with the 216 in the '46. It was diagnosed by the group as many things:
carburetor icing, low compression, etc. So I rebuilt the carb, and the fuel
pump, and fixed the heat riser. No luck.
Checked compression: Dry: 98, 90, 95, 45, 95, 90. Uh oh, number 4 is real
low. So we did a wet test on number 4 and the compression did not change.
O.K., need to do a valve job. When we took the head off, it was obvious that
the exhaust for number 4 was burned - badly burned.
Now I asked you guys again about hardened seats, valve guides, doing all of
the valves or just doing number 4, etc. Again, good advice - go the whole
way.
I did. $400 worth of new valves, seats, guides, lapping, surfacing, etc. The
head looked beautiful. We then put it all back together with new paint and
cleaning everything in sight and torqueing the head bolts to 85 pounds and you
name it, we did it. Clean and nice.
We went to start the beast yesterday and Buddy (the truck's name) had the same
problem as we had at first - hard starting and he would not stay running.
Good fuel, good spark, adjusted the valves loose (Did the preliminary valve
adjustment with the deaf man from across the street who used to work on old
Chevies. He is probably 70 now. It was fun!)
So we checked compression again. Dry: 50, 75, 55, 50, 50, 55. Yikes.
Somewhat depressed, we did a wet test on number 4 and it did not change a
bit.
So, now it gets to be Sunday night. We called our truck club's resident
expert. (He knows engines, he just knows engines.) No real answers. Checked
my doubts: Surface rust on the cylinder walls - no problem. Cleaning the tops
of the pistons with a wire brush and possibly scarring the cylinder walls - no
problem (of course, the wet test would have showed that.) Valves set loose -
no problem.
The only thing that we can think of is that the valve job is bad. I asked the
guys who did the work when they were doing the valve job about being sure that
their work is done correctly. They said that they check each of the valves by
pulling a vacuum on the intake port (I don't know the word here, but it's the
about 1 1./2" round hole that connects to the manifold) and also by pulling a
vacuum on the exhaust port. And again, I do not know the word for the
rectangular hole that the exhaust exits to the exhaust manifold.)
HELP. Any thoughts from you guys? Know that I am sad but up to the
challenge. Just want to do things right and get my Buddy back. I miss him
and feel when he is hurting.
Thanks to all of you for the help in the past and for help now. This is the
great group of guys (or of mostly guys).
Michael Lubitz
1946 Chevy 3/4 ton, stock
1948 Chevrolet 3100, hot rod
Austin, Texas
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