Raw water cooling system.

[spikeitaudi]

I have the boat listed below in my sig. I will have it permanently slipped in the raritian bay which is salt water. What can I expect out of longevity from the engine in regards to the raw water cooling? Seems like most of the boat, bigger cruisers, all are raw water cooling.

Thought or ideas?

Can' wait to get back out on the water Again.

Thanks.

 

[NYBo]

Re: Raw water cooling system.

You will have to replace parts (manifold, riser(?)- not exactly sure since I'm only familiar with outboards) more frequently than you would in freshwater, but people use raw water cooling all the time in salt. I think I've read that such folks replace the parts every 5 years or so. You could look into a freshwater cooling system retrofit and do a cost analysis as to when the break-even point would occur.

I think a bigger concern is preventing marine growth on the hull and outdrive.

 

[keninaz]

Re: Raw water cooling system.

I had and have been around many I/O units and salt water in my life.
The key for your boat, assuming it does not moor in salt water and is removed after each use, is to properly flush the motor when you get home.
You should get many years out of your system doing this.

 

[NYBo]

Re: Raw water cooling system.

He said it will be permanently slipped, Ken.

 

[keninaz]

Re: Raw water cooling system.

OK, missed it.
The degree of salt in the water and the quality of the parts will be all that matters then.

 

[spikeitaudi]

Re: Raw water cooling system.

Quality of part, well it's a Mercruiser engine. As far as growth i am getting it bottom painted. Hull and outdrive. And yes I understand with bottom painting you will still get some degree of growth.

 

[veritas honus]

Re: Raw water cooling system.

You can get a Neutra Salt System. http://www.marinepartsexpress.com/prodbull/NS_engine_flushing_kit.pdf

Flush the engine well with fresh water every time you use the boat. check your annodes(zincs) often, and replace when necessarry. Give the boat a good freshwater rinse every time you use it; and every week or two if you don't use it that often.

 

[dan t.]

Re: Raw water cooling system.

With a full closed FW cooling system the only things that are exposed to salt are the leg, the oil cooler, the heat exchanger, and the risers, run the max amount of anodes and check them monthly, use pencil anodes in the heat exchanger and risers,flush well at the end of the season. The only piece that seems to deteriorate is the risers and they should still be good for at least 5 years

 

[Chris1956]

Re: Raw water cooling system.

Raw water coooling in salt water will slowly eat away the manifolds, risers and thermostat housing, as well as exterior painted steel parts of the motor. Hose off the motor every once in a while to keep the exterior rust down. There is corrosion spray that helps as well.

Expect the risers to last 7-10 yrs, and the manifolds to have similar life. You can pull the risers and inspect them, fairly easily. When rust holes form in the rear part of the riser, downstream of where the waterjacket stops, it is due for replacement. Feel the manifolds for heat every once in a while. If they get too hot to touch, it is time to replace them. Also the brass thermostats will rot out on you as well.

 

[642mx]

Re: Raw water cooling system.

If you have fresh water available at your slip, you may want to consider one of these: http://www.superflushsales.com/sf-400.html

 

[keninaz]

Re: Raw water cooling system.

I knew a guy that installed a valve on his '62 Trojan 30' cruiser to input fresh water into the system and did the same thing. He would insure the engine got to operating temp so the fresh water was in the cooling jackets and leave that valve in the fresh water position when he shut it down. That way salt water was not sitting in them.
If you do that though make sure you remember to put the valve back to the water intake from under the boat or you won't have any cooling water when you get underway needless to say.