On Thu, 22 Jul 2004 17:09:40 GMT, "
wrote:

Thank you, everyone! The problem was a plugged vent- I got it cleared
last night and ran it smoothly for 15 minutes.

It'll be truly fixed when you can run it for 15 NM in short chop. That
loosens the flakes and debris nicely, I find G

R.

Ah, if you are a pessimist you are never disappointed. I write that
with the utmost respect, Rhys, because I have experienced it too many
times in practice.

After 7 NM with moderate waves I got the problem back again. After much
more troubleshooting I found that I have a tiny oil leak somewhere.
Turns out the Yamaha 9.9 is designed to drop to low RPM's and run rough
when it senses a loss of oil pressure. After running at low RPM for a
short while enough oil was accumulating in the reservoir to allow oil
pressure to go back to normal, thus the intermittent nature of the problem.

A quart of oil and 10 NM later the "effect" seems to be gone, although I
still have to find the leak causing the problem.

Mike

rhys wrote:

On Thu, 22 Jul 2004 17:09:40 GMT, "
wrote:


Thank you, everyone! The problem was a plugged vent- I got it cleared
last night and ran it smoothly for 15 minutes.


It'll be truly fixed when you can run it for 15 NM in short chop. That
loosens the flakes and debris nicely, I find G

R.

Factory prop or did you change it for one with a different pitch?


"rhys" wrote in message
...
On Wed, 21 Jul 2004 12:06:32 GMT, "
wrote:

Thanks everyone! The gas was new last weekend, so I don't think that's
the problem. I'll check the other things when I get back into town
tomorrow.
Thanks again,
Mike

Another possibility which happened to my four-stroke Honda 9.9 is a
stuck carb float, which make for harder starts, limited acceleration
and the occasional stall. It needed a good clean due to crap in the
gas.

Filtering the gas/cleaning the tank is always a good idea.

R.

On Wed, 28 Jul 2004 13:40:34 GMT, Mike_H
wrote:

A quart of oil and 10 NM later the "effect" seems to be gone, although I
still have to find the leak causing the problem.

Interesting. Does it leak at rest or only when under load? What I am
getting at is does the rising engine heat cause a gasket somewhere to
fail, or is it the rising oil pressure that forces oil past a hole or
gasket or crack or something that "closes" or reseats itself when the
motor cools down?

I'm glad you are getting closer to the ultimate problem, which isn't
fuel, it seems. Believe it or not, that's a good thing G

R.

I replaced the factory prop with a plastic one of the same pitch.
Mike

Michael wrote:

Factory prop or did you change it for one with a different pitch?


"rhys" wrote in message
...

On Wed, 21 Jul 2004 12:06:32 GMT, "
wrote:


Thanks everyone! The gas was new last weekend, so I don't think that's
the problem. I'll check the other things when I get back into town
tomorrow.
Thanks again,
Mike

Another possibility which happened to my four-stroke Honda 9.9 is a
stuck carb float, which make for harder starts, limited acceleration
and the occasional stall. It needed a good clean due to crap in the
gas.

Filtering the gas/cleaning the tank is always a good idea.

R.

It is leaking at rest. When not running I keep it locked in the up
position and out of the water. When I put the motor down and into the
water I have found a small amount of oil comes out of a timy breather
hole in the upper case of the motor. I haven't had the motor in the
down position long enough to determine whether it also leaks when running.

My plan is to identify where the at-rest leak(s) is/are occuring, repair
it/them and then look for evidence of running leaks. It'll be slow, but
I know I'm making progress.
Thanks,
Mike

rhys wrote:

Interesting. Does it leak at rest or only when under load? What I am
getting at is does the rising engine heat cause a gasket somewhere to
fail, or is it the rising oil pressure that forces oil past a hole or
gasket or crack or something that "closes" or reseats itself when the
motor cools down?

I'm glad you are getting closer to the ultimate problem, which isn't
fuel, it seems. Believe it or not, that's a good thing G

R.