Same head. It does make a very light ticking sound, but that sound does not
increase with throttle. Would advancing the timing be to the right or left
of the line? also, would the adjustment of the rocker arms cause this
issue? And one last thing, I did put new plugs (gapped them) & wires in it
too.

"Gudmundur" wrote in message
...
In article ,
says...

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?



So, I am guessing it did run better back before the burnt valve, and gave
you more power. If you had the head off, then you must have had to adjust
the valve lash. Back off until you hear the tick-tick-tick, and then
tighten
slowly until the ticking stops, and adjust 1/4 to 1/2 turn more. Also,
play
with the ignition timing. It may be just a bit late, advance it a bit and
'road test it'. Listen for the ping of detonation, in case you advance to
far. Also remember an over advanced motor will often not start when hot,
it
will actually kick backwards and try to rip the starter right off the
engine. If you feel the engine doesn't make the power it used to, a bit of
tweaking is in order. Hope the new head is the same as the old head. You
did say you replaced the head? 67CC chamber vs. 73CC chamber? Port sizes
differant?