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Got a 7.0 BCG that's acting up like this:

slow to start, and when it does, the rpms run up and down, like it's
not getting enough fuel. The voltage never gets up to 110v, and in
fact stays around 50 volts. sometimes, it will kind of bog down on the
start, backfire, and then goes up to 110v. If I go look in the water
around the exhaust, there's carbon floaters all over the place. This
is all with no load.

It did this for a while in November, and I think the mechanic that
looked at it just made the mix more rich. then it started, and
backfired every time until last week, when it went back to the low
voltage and wandering rpms.

I know I've got a bunch of things to try, but wanted to see if there's
a
"seen that, did this" out there to shorten the troubleshooting.

Thanks as usual.

IMHO, you have an injector nozzle the is leaking down into the cylinder
while it is stopped.. Then that injector is dumping raw fuel into that
cylinder while running.. (Hence the black carbon and oily film in the
exhaust).

Until you get the engine speed stablized the generator can't settle down to
the required frequency or voltage.


--
My opinion and experience. FWIW

Steve
s/v Good Intentions

"Steve" wrote in message ...
IMHO, you have an injector nozzle the is leaking down into the cylinder
while it is stopped.. Then that injector is dumping raw fuel into that
cylinder while running.. (Hence the black carbon and oily film in the
exhaust).

Until you get the engine speed stablized the generator can't settle down to
the required frequency or voltage.

So, you think I'm a carb cleaning (and rebuild) away? Could be. I know
the boat sat for a while.

I made the assumption that this was a diesel when you mention Westerbeke.

I'm not familiar with the model number you gave but from your latest
response and mention of "carb cleaning" then you must be dealing with gas
engine..

However, the problem still seems like a very rich fuel mixture, like running
with the choke closed or float level is too high or the float is stuck..
Rebuild the Carb!


--
My opinion and experience. FWIW

Steve
s/v Good Intentions

Had some more time to mess with this today.
Here's an update on the symptoms.

Gas genset, 7Kw Westerbeke 1998. Looks like the carb has probably been
off (no red paint). Other than that, no visibile repairs/replacements.

To start this unit, you push a button that instead of preheat, it
bypasses the low oil shutdown, it runs the fuel lift pump, and
energizes a choke solenoid that closes the butterfly in the carb.

What I first found was that the unit would wander in RPM (like
starving for fuel, running down, and recovering right before it
stumbles) unless the choke butterfly was physically held in the closed
position.
After a while, the unit stopped wandering, and settled in to it's 1800
RPM.

The output voltage, however is around 100 volts AC, and may vary
between 95 and 105 volts.

Running appliances like the air conditioners will only be successful
for a few minutes. Then the Cruiseairs shut down, with a LO AC error
message on their displays.

I pulled the rectifier, and checked it with a meter in the diode mode.
It appears to be intact. I did notice some corrosion from one leg to
the case. Hoping that was it, I cleaned it thoroughly, but no deal.
Still at 100 v max.

What's the next thing you would look at? I'm thinking an electrical
problem now. How would one check things like the windings?