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Peter Bennett
 
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On Tue, 14 Jun 2005 08:15:56 -0700, "Steve" wrote:

In an earlier post I mentioned that I had changed props and the engine was
only reaching about 2200 rpm.

My (new) MD2B manual indicates this engine should produce 25 hp at 2500 rpm.

Yesterday while running the engine in neutral at the dock I noted that the
governor is limiting the engine rpm to 2200 rpm.

I hesitate to tamper with the governor settings and the OEM seal wires are
still in place.

I wonder if I should investigate this situation or be satisfied with the
2200 rpm since my boat reaches hull speed at this rpm.

Any comments or suggestions would be appreciated.

Steve
s/v Good Intentions


Since you are getting fairly close to the advertised top RPM, a good
question to ask might be "Is my tachometer reading correctly?"

Depending on your tachometer arrangement, there are several ways the
tach may be mis-reading. Mine senses the frequency of the AC produced
by the alternator, and probably (I haven't had reason to look, yet)
has a calibration adjustment, since the alternator speed vs engine
speed will depend on pulley diameters.

Talk to a mechanic to see if he has some independent means of
measuring engine RPM. I recall seeing a portable mechanical tach that
could be held against the end of the crankshaft.


--
Peter Bennett, VE7CEI
peterbb4 (at) interchange.ubc.ca
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