Freshwater Cooling Kit - Full or Half?

[kwoolard]

I want to install a freshwater cooling kit on my 5.7L Alpha I Gen II engine which has never seen saltwater in its life. The boat is a 1999 but the engine was new in 2004. Original manifolds and risers were put back on the new engine. I will probably be using the boat in saltwater about half the time and the other half in brackish water. Should I go ahead and purchase a full system or do you think the half system would work if I flush the raw water side of the cooling system with Salt-Away after every use?

 

[Haut Medoc]

Re: Freshwater Cooling Kit - Full or Half?

Generally speaking, if an engine has been run in raw water for more than 100 hours or is older than 1 year it is not a candidate for a close cooled system......
If you must do it, I would go with a full system & replace the manifolds/risers at the same time......​

 

[kwoolard]

Re: Freshwater Cooling Kit - Full or Half?

What makes it not a candidate? Is it that the corrosion process has already begun? Are you saying that installing a kit now, since the motor is over a year old, is no better than just flushing the engine with salt-away after every use?

 

[Haut Medoc]

Re: Freshwater Cooling Kit - Full or Half?

All I'm saying is that the potential for the heat exchanger to get full of scale is increased by it's age.....
The benchmark is set by Merc.....
You might be Ok, but if you are going to a full system, change the mans/risers, to prevent even more scale, & I would check/change the coolant at least once after some operation.....
If you are going half system wait until they need to be replaced......
If the engine has three years of saltwater use, saltaway or not, I would say you are wasting your time.....
This is my opinion, let us know how it works out....
The anti corrosives in anti freeze will do more to proect the inside of the engine than salt away will by far....​