Converting to Fresh water Cooling

[Mnemonic]

How expensive is this to do on a 5.0L Mercruiser? I heard this is a great upgrade for your motor, especially to us salty dogs down in Long island!

 

[tommays]

Re: Converting to Fresh water Cooling

its a littel late to change now to much rust and scale in the motor to clog the exchanger<br /><br />now a good long island fresh water flush EVERY use will really help<br /><br /><br />tommays

 

[Olds Eddie]

Re: Converting to Fresh water Cooling

It is easy to clean out the exchanger if scale and rust do build up. Also it sure makes winterizing easier. I use my boat to fish year round and all I have to do in the winter is drain the risers, and make sure the outdrive is down. the cxchanger and raw water pump seem to be self draining. I used a San Juan Engineering system and it went on in a day, However I had to put an engine driven raw water pump on to supply enough water to cool the engine with Alpha 1 outdrive.

 

[Mnemonic]

Re: Converting to Fresh water Cooling

I know right before i bought this boat the risers were replaced and the motor went thru a tune up.<br /><br />How do i flush a I/O? I know how to do a fresh water flush on a O/B, but this is my first I/O,

 

[tommays]

Re: Converting to Fresh water Cooling

you can use the merc muffs with the pin that keeps them on the drive and just raise and lower the drive to put them on<br /><br /><br />or if you search here many people have set up valves that allow the boat to flushed with a hose and divert the drive water overboard<br /><br /><br />tommays

 

[Haut Medoc]

Re: Converting to Fresh water Cooling

Flushing an I/O is surly similar to flushing an O/B, Put it on the muffs and let it run. There are various kits with additives that you can use to flush. I have FWC so I don't really have any info. on that. In my unexpert opinion however, is that tommays is right, it's to late for an engine that old to go FWC even if it spent its' life in fresh water. Rust and scale build up will choke the exchanger quick and you will over heat and be wondering why. Do it when you are ready to re-power,(to a 350).You'll have to get new manifolds and a new engine water pump to be totally rust free, but you will get long engine life, even from a re-built engine.........J