"1.156" wrote
My Yanmar 2gm used to go 3400 rpm -- I did it a couple of times just to
see if it would go the recommended redline. But now it will only go
2800 rpm full squeeze. And at 2800 rpm (either at the slip or under way)
it puts out a little whitish smoke. I've been thru the fuel system and
so far can't find anything that would be limiting the fuel flow (new
hoses, new filter elements, etc).

Any suggestions of other reasons this thing won't go full blast.?


Are you sure about the rpm? Some aftermarket tachometers have to be set up
for the number of teeth on the flywheel and can lose this setting. If it is
the factory tach, you should be ok.

Other things could be:
- fuel starvation (Racor or engine filter plugged)
- high pressure pump needs rebuilding/replacing.
- Exhaust elbow plugged - Take it off and inspect exhaust and water sides.
- Throttle cable stop incorrectly set
- Governor incorrectly set.

I am not sure, but I believe that the engine will not run at full rpm with
no load - something to do with the governor.

If you can't find the problem yourself (you should have manual to understand
how it all works), check with an experienced Yanmar mechanic who has seen
this type of problem before - otherwise you may change everything before you
find the cause!

There are also other internet forums that discuss Yanmars - I think that
Torreson have one http://www.marinedieseldirect.com/power/forums.php and
then there is http://www.yanmarhelp.com/

Good Luck