your thoughts on this

[karatejoe]

I was talking to a marine mechanic who works at a reputable dealer. He said it was a waste of time to flush your motor with fresh water. Whether you flushed the motor or not the life of manifolds etc etc did not extend any longer than if you didnt. He stated the block"s cast was to thick for the salt water to make a difference to. He never flushes his block. He said to hose down the boat and stern drive and forget the rest.
Maybe he might be trying to drum up business for himself.LOL
I flush mine but am rethinking it. I will have to do more research before i actually stop.

 

[Glastron_V210]

Re: your thoughts on this

I don't know what you have, but I have an Alpha merc.

There is a bad spot just inside the bell housing where the cooling water goes in (Raw water).

It build salt and corrodes there really badly. I had to repair my bell housing because of this.

I flush to avoid this spot screwing up again. But, I don't loose sleep if I take it out and don't flush once in a while. I'm closed cooled on the block and manifold though, and I'm still on 1978 originals I think. The risers are a different story though.

Chay

 

[Mariah218]

Re: your thoughts on this

Thats absolute nonsense. Its the sort of thing you learn in 1st grade, put a nail in a cup of salt water and put another in freshwater. The insides of risers and mainfolds is bare cast iron, it corrodes at even the sight of moisture, and salt is a catalyst for corrosion. Volvo actually do a salt neutralising kit which flushes the system with a pH neutralising agent.

In summary, and you can find many posts to back this up, boats run in salt water manifolds and risers have much shorter lives precisiely because of this. Always flush your engine with fresh water if you can, its a known fact that it will increase the life of your block, mainfolds and risers - fact.

 

[Mariah218]

Re: your thoughts on this

Thats absolute nonsense, your marine mechanic is talking rubbish. Its the sort of thing you learn in 1st grade, put a nail in a cup of salt water and put another in freshwater, you all know the rest. The insides of risers and mainfolds are bare cast iron, it corrodes at even the sight of moisture, and salt is a catalyst for corrosion. Volvo actually do a salt neutralising kit which flushes the system with a pH neutralising agent.

In summary, and you can find many posts to back this up, boats run in salt water manifolds and risers have much shorter lives precisiely because of this. Always flush your engine with fresh water if you can, its a known fact that it will increase the life of your block, mainfolds and risers.

 

[zbnutcase]

Re: your thoughts on this

Funny part is most all auto based marine engines break or freeze crack long before the iron rots out. I never flush mine, nor do I care; its just an engine, will replace when I need to.