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axelkloehn
08-02-2010, 03:51 PM
last friday just before engine install I found out my bravo raw water pump is leaking. Opened it up and saw that the shaft is rutted from the radial seals and the body is heavily corroded between the two seals. It will never be leakproof again and went straight in the trash can...

....think about replacing it with a crank mounted Johnson F6B- price is much friendlier and changing impellers is easier- but I read there are different opinions about it. Some say you loose speed, some say you gain speed- does not matter for me, I don't mind the +/- 3 mph...
But I read it builds up too much pressure which might be a risk for head gaskets and other components? Is that true and how can I deal with that??

Planetwarmer
08-02-2010, 04:02 PM
what did you decide to do on the motor issue?

I know guys often install over-pressure relief valves to keep the pressure in check.

axelkloehn
08-02-2010, 04:10 PM
what did you decide to do on the motor issue?

I know guys often install over-pressure relief valves to keep the pressure in check.

...for this year a sbc 350 merc, will check the 455 olds when I have time and mood to do so, wanna ride the boat before the season is over...

How does this over-pressure relief looks like and where do you install it?

MOP
08-02-2010, 05:03 PM
I doubt that you will need the pressure relief valve if you by the small block version of the Johnson, it supplies about 30% less volume than the BB model but is still adequate for a future fresh water cooling setup.