Crusader CH350 heat problem

" I have a twin CH350 installa

" I have a twin CH350 installation in a 1980 boat. A while back I had a temp problem with both engines which was ultimately traced to plugged heat exchangers. During the diagnosis I replaced the thermostats on both engines. After fixing the heat exchangers both engines run at acceptable temperatures. But, one engine now warms up much faster than the other -- this didn't happen before --, heats up more at idle -- the cooler engine idles at about 135-140 degrees (160 degree thermostats in both) where as the problem child idles at 160-170 degrees --, and runs warmer under load -- 175 degrees verses 165-170 for the cooler engine. The baffling thing is that both engines used to warm up at just about the same rate, ran cool at idle, and ran at just about the same temperature under load. The heat exchangers have been freshly serviced -- both coolant and oil coolers -- , the sea water pumps are low hours with new impellers, and the mixing elbows were replace 3 years ago. I'm about to try a new thermostat in the hot engine. Any opinions on whether I'm on the right track? BTW, I just replaced the circulating pump on the hot engine, it was squeeling -- quiet now, but the temp behavior hasn't changed. "

" For all you out there just w

" For all you out there just waiting to hear what was causing this problem, here it is. The thermostat was in the wrong place. This is a 1980 Crusader big block which has a large double chambered thermostat riser. Some of them have a relief valve in the second chamber some just a restrictor. Anyway the thermostat was mounted down in the intake manifold (auto installation location) rather than in the riser. New thermostat in the correct location and now the engine warms and runs normally. "

" Chuck,
Thanks for posting t

" Chuck,
Thanks for posting the solution to your problem. I hope people are searching the existing messages for answers to their questions before they post... (use the Keyword Search link on the left) so posting an answer to your own question is very helpful!
Regards,
Andrew "

" I HAVE A 9.9 h.p. JOHNSON MO

" I HAVE A 9.9 h.p. JOHNSON MOTOR and when i sstarted it up this spring i noticed that ther e was no water coming from the rear port. it was running at idle at the time, does it have to be running faster or do i hav e a bad/plugged water pump and how do u get into it to fix it .THE motor is bout a 1970 Thanks "

" Don't have a lot of expe

" Don't have a lot of experience with these small outboards. The outboard needs to put out a stream at idle, otherwise it isn't cooling. One thing I have seen is the pump didn't get drained during fall layup (owners manual should tell how to drain pump). Freezing causes the pump body to burst and no cooling next spring. Could be something clogging the intake. Maybe the impeller has gone bad, like they do on inboards. No matter what the problem turns out to be, check the impeller as they don't like to run dry. "

" No, Outboards are self-drai

" No, Outboards are self-draining. There is no need to drain the pump. The most likely cause for your situation is a blocked telltale fitting. Insects like to climb into these tight places during the off season and set up home. You will probably find that if you plunge the fitting with a piece of wire the blockage will be dislodged and the water will be evident. If not, then start looking further. Good luck. "