Raw Water Cooled Moves To FL

[BonBini]

Sold my first boat to a friend in S. Florida. LiL BonBini spent her entire life running in the fresh waters of lower Michigan. When I got her with 1250hrs showing, she was with coolant system rust to the point of coolant regulator and housing repair needed. The manifolds and risers looked to be original. I didn’t really run the boat more than a tank of gas.

I spoke with my friend before the purchase about risers and manifolds being part of b-o-a-t maintenance. LiL Bon has been down in the Atlantic, at a private dock for seven mos now. In the water the whole time. Sounds like she gets out one - two times a week.

My friend tell me he gets in the water (2-3ft), puts the muffs on and rinses her out after every run.
I’m getting a little concerned it may be very close to before failure manifold time! What do you guys think?

Also: What do you guys think of a Fresh Water Conversion Kit at manifold time vs. muff rinsing or some sorta dock hose rinse?

Many Thanks. …Ron

 

[Captain Crispy]

Definitely should be changing the manifold, risers, etc soon as a preventive measure.

Also, I think it is too late to to convert that block to freshwater cooling. At least one manufacturer advises against it one the engine has 50 hours in salt water or 100 in freshwater. Seems the anti-freeze/coolant will react with the deposits of corrosion and salt in the small passages of the engine, causing the liquid to thicken and block passages.
The Monitor system supposedly can by installed anytime, but it is still the same antifreeeze/coolant.

 

[tobnpr]

Me, I wouldn't even run the boat with manifolds and risers that old.

Although I've since repowered, my Chris-Craft had a RWC 350 Indmar for years. I flushed most of the time, but not always. I neglected the risers/manifolds a bit too long (7 years) and one failed-fortunately at the dock and not while running. When I pulled the heads for replacement and looked inside the block, it was like new. Unlike the thin castings of the manifolds and risers (and sometimes the crappy, razor-thin gaskets) the blocks themselves aren't as much of a concern in saltwater.

Replace the manifolds and risers ASAP, and continue flushing after every use. I used to use Saltaway- good stuff, and leaves a protective coating on the engine internals.

 

[BonBini]

Captain Crispy/tobnpr: Thanks for the info and personal experience.

For some reason I was thinking a new set of manifolds/risers might only go 3 years down there. So investing $800 or so on a FWC kit might be a good move. But if they can go twice as long as we expected, well then perhaps one more set will finish off the motor. ...Ron