Sea water pump

chambers1517

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I have a 350 mpi and the sea water pump is different. It has a stack and has 2 air lines coming out of it. What is the purpose of all this extra junk on the water pump.
 

GA_Boater

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Since the sea water pump is attached to a motor and considered part of the engine package, what motor is it?
 

chambers1517

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It is an 08 350 mag mpi and bravo 1 drive.[FONT=Tahoma, Geneva, sans-serif] There are 2 air lines that come out of it and go to a round ball on the bottom right of the engine and one goes back to the fuel pump.[/FONT]
 

alldodge

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I have a 350 mpi and the sea water pump is different. It has a stack and has 2 air lines coming out of it. What is the purpose of all this extra junk on the water pump.

This is an air actuated drain system and is used during winterization. There is a air pump on top the motor, along with a pull to valve and fitting. They work great so long as they are working "correctly", the key is correctly. Over time issues can arise like getting crud in some of the lines or valves and not all the water will come out. A few have found cracked blocks in the spring. In any case here is a link of another which had the same question and there is a link in post 5 to boatinfo which has the procedure to correctly drain the system when it comes time

http://forums.iboats.com/forum/engi...-mag-air-actuated-single-point-drain-system-q
 

GA_Boater

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Moved this into the Mercruiser section for easier finding by others looking for info on this winterizing procedure.

Also, this link is to the Air Actuated Single Point Drain System. It sure looks like the old manual method is still better or as Merc calls it, "3 Point Manual Drain System" - In or out of the water. http://boatinfo.no/lib/mercruiser/ma...ser31.html#/86
 

Bt Doctur

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More like"3 point cracked engine block" The Bravo pump is mounted to the engine and has nothing to do with the air hoses
That"fuel pump" is the "cool fuel unit" and uses the raw water to cool the fuel to help prevent vapor lock
 

Bt Doctur

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I stand corrected, but its still a stupid system . Old school= drain plugs
what manual is that in ?
 

chambers1517

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Ill have to get some serial numbers. I took the sea pump off and it was a major pain with the added length due to the air line contraption. I was disappointed to see the impeller looks brand new. I was hoping it was shot and was the cause of the 2 beeps per minute. The temp sensor is fine also so what is next. Im still going to rebuild the pump, the backing shim had some wear on it.
 

chambers1517

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Aug 14, 2009
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Thanks ALLDODGE. I worked this weekend and am waiting on my water pump parts. Ill put it back together and check the oressure sensor.
 
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