Thread: Low RPM
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calhoun
 
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"nate" wrote in message
...
ok,

350 gm mercruiser.

I had a burnt valve. I took the head in to the machine shop and had it
replaced. I put it back together, did the timing ect. It is running a
lot better, but doesn't seem to have the full power. On the engine it
says that the max rpm should be 4400 - 4800. Although I only seem to be
getting 4200 at the most. Also it seems a little slugish out of the hole.
I checked the compression on all clyinders and they are all very good.
(160-170). I feel as though it might have something to do with the
timing. I read in a book that the timing mark should hit in the same spot
everytime. It's pretty close but seems to very about 2-3 degrees each
time. Might this be the issue?

Any thoughts on what the problem might be here?

You have had this running 44-4800 at some time? If it never ran that speed
than you need a smaller pitch prop.
If it did run at speed and all you changed was the head than timing may be
an issue. Advance it 2 degrees at a time till you hear knock. See if that
picks it up a bit.
You did follow the timing instructions and remove/plug correct hoses or
disconnect certain wires (you didn't mention the year so I don't know what
kind of ignition you have)