what is causing the boat to do this after replacing all of these things and it s

[searay3]

Re: what is causing the boat to do this after replacing all of these things and

Re: what is causing the boat to do this after replacing all of these things and

Not......the circulating pump does not have a water tight seal at the impellor. The outdrive pump could very well get water into the engine, but it;s not nearly enough to circulate throughout the system. If it wasn't necessary, the Merc engineers would not have it on the motor. I don't know if your FWC or RWC, but the circulating pump needs checked. Simply remove the belt and spin it, if it's broke you'll know, but they usually leak if they are broken. If it checks ok, you have a restriction somewhere and will need to find it. One other question. When you have muffs on, does the water come running out at the transom or trickle? Might just have to start pulling the hoses one by one with the muffs on and see where the water stops/slows.

 

[searay3]

Re: what is causing the boat to do this after replacing all of these things and

Re: what is causing the boat to do this after replacing all of these things and

Thought just hit me, if an auto type water circulating pump was used in a rwc system, the impellor could have rusted away enough that it no longer does it's job. Auto uses a steel impellor, marine I believe uses brass or SS, (never looked inside) hence the difference in price.

 

[QC]

Re: what is causing the boat to do this after replacing all of these things and

Re: what is causing the boat to do this after replacing all of these things and

Are are you getting water flow out of the propeller when on muffs? Got to flow out to get good flow through. This came to mind becasue it cools off quickly when you pull the plugs, hence flow . . .

Also, you said that you replaced the exhaust elbow and that you have followed Don's advice, did you check the manifold as opposed to just the elbow?

 

[rogerwa]

Re: what is causing the boat to do this after replacing all of these things and

Re: what is causing the boat to do this after replacing all of these things and

this has not been specifically addressed but the temp on the Thermostat should be about 145. When testing in the pan, it should open up at that temp or darn close. If you have the wrong temp thermo, it will obviously run hotter. Auto Thermos are much higher.