The thermostat is in a small housing that the discharge hose is attached to
so it's kind of like closing a valve on you garden hose, water pressure is
still there but can't get out. So if the stat is stuck shut all the impeller
is doing is churning water with a small dribble ...( much like a 90 year old
guy peeing) coming out the discharge tube. The rest stays in the block
getting hotter. Now this is all in relation to a 25 hp merc but I've seen
and worked on some of the smaller and larger 2 strokes and they have been
basically the same. If there is a stat housing it will be a noticeable part
bolted onto the powerhead with a 90 deg fitting threaded into it. If its an
earlier model, early 90's or before if I remember right, the fitting is
threaded into the block , no extra bolt on housing. That style will not have
a stat. Now as Rick said the quickest way to tell if the stat is stuck, is
to take it out and try it. If still no flow then the feed tube inside the
leg may not in position at the powerhead or at the impeller end. That tube
can be a bitch at times to get in place as your working almost blind and buy
feel. Another problem may be the key that locks the impeller to the
driveshaft. I've forgotten that a time or two but usually notice it sitting
on the bench before it's all back together :-) Other than that the only
other thing I can think of is it may have a massive blockage of mud or
whatnot in a 2 part sandwich kind of part that is one side coolant flow and
the other side exhaust flow. It's at the back of the block on what would be
a cars driver side.
Jim
"Garland Gray II" wrote in message
...
Rick, Jim, or anyone else,
Wouldn't the same volume of water flow thru the pump and out the discharge
(part of which would be indicator stream) regardless of the state of the
thermostat ? I had assumed the thermostat merely diverted cooling water to
the powerhead , as needed. I don't know for sure, but would like to know,
if someone can say.
A few years back, my first ebay purchase was for a kit to force a
regulated amount of fresh water back thru the "pee tube" to flush out the
outboard motor. At the time, i was skeptical whether this would flush out
more than just the water pump, but figured what the heck.
I'm still skeptical, so would appreciate it if someone who is familiar
with these cooling system could tell me.

wrote in message
...
On Sun, 16 Mar 08, Frank wrote:
I made sure the water level in the barrel was well
above the water intake.

Make sure it's higher than the impeller. There's no mark on the
outside of your lower unit indicating where it is, you'll just have to
estimate. But some impellers won't suck up water if they're above
water level.
Second thing, remove the thermostat. It might be stuck closed. It
won't hurt to run the engine without it. If that's the problem, you
can replace it later.

Rick