Rod,
The motor is a 1995 model. It doesn't have oil injection. The oil
goes into the gas tank. The original owner stated that the boat &
motor only had about 30 hours total and that it had been about a year
and a half since it had been in the water. Since it stalls when warm,
I'm more inclined to believe that vapor lock is causing my problem. I
will have the impeller checked out as soon as I can find a Mercury
Force mechanic who is not swamped with work.

Thanks all for your input. It is most appreciated.

Harvey
"Rod McInnis" wrote in message ...
"Harvey Arkawy" wrote in message
om...
This is for any of you with the "Know". A month ago, I purchased a
bass boat with a Mercury Force 70 hp motor with approximately 30 hours
of run time.

Is this a new motor, or an old motor that hasn't been run very much?


This past Thursday, I put 12
gallons of 89 octane into the tank and added 31 ounces of 2 stroke
oil.

You mixed the oil into the gas?

Doesn't your engine have oil injection?


what do you thing could
be causing the motor to labor and stall and not re-start? I am
prepared to take it to the local boat mechanic and have them do a
tune-up.

Sounds like a classic case of fouling plugs. It is common for two cycle
engines to get an oil buildup on the plugs which makes the engine run poorly
and hard to start.

I asked about the oil injection because if you are adding oil to the gas,
and the engine is injecting what it thinks it needs, then you will have
twice the oil and fouling is much more likely.

Another reason that the plugs could foul is that the spark is weak. A weak
spark may be okay when the plugs are new but once they get a coating of oil
on them the spark may not be strong enough to burn through the layer of oil.
You may also be running the incorrect spark plug, check the owners manual
for the proper spark plug number.

While you should certainly fix the fouling problem you might also want to be
alert to the symptoms. As soon as the engine starts to miss put it in
neutral and rev the engine up a bit.


Rod