Boston Whaler 15' Rage Overheat

I have a '94 rage with the 90hp OMC engine. My girlfriend started the
engine at the dock and reved it up in neutral, which as you know can divert
some of the thrust down to the bottom. It kicked up a lot of sand and
gravel, some of which might have gotten into the cooling passages. The
overheat alarm goes off after the engine is used a while. I narrowed down
the problem by checking the heads with my hand and unplugging the integrated
sensor located in the middle of each head. I then disconnected all the
hoses I could to try and see where the water was flowing/not flowing, and
blew into them to try and dislodge any small stones. It didn't help much.
My next step is to try and reach the water hose at the bottom of each head
and see what the flow is there, then use a water hose to try and
power-backflush each hose I can reach. If that fails, I guess I'll get a
book and see about taking off the head on the bad(starboard) side. I
noticed that there is a "plate" around the plugs that looks like it can be
removed without taking off the heads. Maybe that would reveal the water
jacket of the head? Another question is where the thermostat is on that
powerhead? I didn't see it on the top of the heads anywhere.

"Chris S." <christophersouth DeleteThis @msn.com> wrote in message
news:d84bdd11.0408151144.2daf8965@posting.google.com...
 > I just boat a '95 rage with 115HP in good shape last month. We've had
 > two outtings of a 2 to 3 hours and the boat has shut down both times.
 > The RPMs dropped to about 2000 from 4500 when at full throttle before
 > the engine shut off and wouldn't restart until it cooled off. The
 > overheat alarm didn't sound, but the second time I noticed that the
 > thermostat was almost 220 degrees.
 >
 > Any suggestions on what I should look into?<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Boston Whaler 15' Rage Overheat 

I haven't had a chance to look for the thermostat on the engine yet.
I did try to flush the engine with the adapter that I got in the sale
to see if there was any blockage in the hoses -- I'm curious if I'm
doing it right. I pulled the impeller case back and plugged the
adapter into the casing that was pulled away from the engine (kind of
hard to explain without a picture...). Is that the right place to
plug in?

Floyd suggested a new engine, anything else to check before I go that
way? What's a rough cost of new engine?


"Floyd in Tampa" <Flooydomit RemoveThis @prodigy.net> wrote in message news:<J0WTc.1092$Dq5.899@newssvr16.news.prodigy.com>...
 > I have a '94 rage with the 90hp OMC engine. My girlfriend started the
 > engine at the dock and reved it up in neutral, which as you know can divert
 > some of the thrust down to the bottom. It kicked up a lot of sand and
 > gravel, some of which might have gotten into the cooling passages. The
 > overheat alarm goes off after the engine is used a while. I narrowed down
 > the problem by checking the heads with my hand and unplugging the integrated
 > sensor located in the middle of each head. I then disconnected all the
 > hoses I could to try and see where the water was flowing/not flowing, and
 > blew into them to try and dislodge any small stones. It didn't help much.
 > My next step is to try and reach the water hose at the bottom of each head
 > and see what the flow is there, then use a water hose to try and
 > power-backflush each hose I can reach. If that fails, I guess I'll get a
 > book and see about taking off the head on the bad(starboard) side. I
 > noticed that there is a "plate" around the plugs that looks like it can be
 > removed without taking off the heads. Maybe that would reveal the water
 > jacket of the head? Another question is where the thermostat is on that
 > powerhead? I didn't see it on the top of the heads anywhere.
 >
 > "Chris S." <christophersouth RemoveThis @msn.com> wrote in message
 > news:d84bdd11.0408151144.2daf8965@posting.google.com...
  > > I just boat a '95 rage with 115HP in good shape last month. We've had
  > > two outtings of a 2 to 3 hours and the boat has shut down both times.
  > > The RPMs dropped to about 2000 from 4500 when at full throttle before
  > > the engine shut off and wouldn't restart until it cooled off. The
  > > overheat alarm didn't sound, but the second time I noticed that the
  > > thermostat was almost 220 degrees.
  > >
  > > Any suggestions on what I should look into?<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Boston Whaler 15' Rage Overheat 

 >
 > Floyd suggested a new engine, anything else to check before I go that
 > way? What's a rough cost of new engine?
 >
I didn't suggest a new engine....that was JohnC. You may only have a
partial blockage and the engine may not be damaged. My overheat sensor
activates before the head gets to the boiling point, at least on the
outside. You can dribble water on it and it doesn't boil or steam when the
alarm starts. When the engine overheats to the point of making steam, I
wonder if it would be visible?
I haven't heard of the flushing device you mention, but it couldn't hurt.
Let me know if it works to clear your engine, assuming that's the problem.<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Boston Whaler 15' Rage Overheat 

Try asking at <a style='text-decoration: underline;' href="http://continuouswave.com/cgi-bin/Ultimate.cgi?action=intro" target="_blank">http://continuouswave.com/cgi-bin/Ultimate.cgi?action=intro</a>

LOTS of whaler folks there.

--
Chuck Tribolet
triblet.DeleteThis@garlic.com
<a style='text-decoration: underline;' href="http://www.almaden.ibm.com/cs/people/triblet" target="_blank">http://www.almaden.ibm.com/cs/people/triblet</a>

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"Chris S." <christophersouth.DeleteThis@msn.com> wrote in message news:d84bdd11.0408151144.2daf8965@posting.google.com...
 > I just boat a '95 rage with 115HP in good shape last month. We've had
 > two outtings of a 2 to 3 hours and the boat has shut down both times.
 > The RPMs dropped to about 2000 from 4500 when at full throttle before
 > the engine shut off and wouldn't restart until it cooled off. The
 > overheat alarm didn't sound, but the second time I noticed that the
 > thermostat was almost 220 degrees.
 >
 > Any suggestions on what I should look into?<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: Boston Whaler 15' Rage Overheat