Newbie question Fresh water to salt water conversion

[Learo2000]

I am buying a new for me, used boat, from my brother in Michigan. IT is a 1988 201 liberator with a 350 OMC/Cobra with 144 hours on it.<br /><br />I will be mouring the boat in the Puget Sound. <br /><br />1. Is it a good idea to convert to a closed water cooling system.. or if I flush it, hose by my slip, will I be ok.....<br /><br />2. Should I get bottom paint put on it?????<br /><br />Any comments greatly appreciated... anything else I should look at doing for a fresh water to salt water conversion.....

 

[Boatist]

Re: Newbie question Fresh water to salt water conversion

Learo<br />That is a hard question. Most of the saltwater problems are with the exhaust manifolds and risers. Last about 4 to 6 years in salt water. The Fresh water cooling system will protect only the engine. While it protects the engine and let engine run a little warmer (a good thing) also can add some extra problems. If you get a small water leak can run out of water and over heat. It does allow the engine to run at a more even tempature as do not have 45 degree water going into engine. I would reccommend you ask other boaters in your area. As long as you never run out of water I think Freshwater cooling is a good thing. I am sure will get more ideas here.

 

[Learo2000]

Re: Newbie question Fresh water to salt water conversion

Thanks for the info..... any more comments??? I think I am going to lean to not putting on a closed water system and try to flush it with fresh water as often as possible..... thanks again Doug

 

[DJ]

Re: Newbie question Fresh water to salt water conversion

Learo,<br /><br />If it were me, I would do both.<br /><br />Closed cooling-There are many systems available that cool the manifolds as well as the engine.<br /><br />Bottom Paint-If you're going to leave it in the water, it's a necessity. Without it, you'll be sorry when you pull it out. The bottom paint will also protect against blisters.

 

[Learo2000]

Re: Newbie question Fresh water to salt water conversion

I am sure I will get the bottom paint.. is this somthing I can do myself.. or should I have a local marine do it????? it will be the first coat.<br /><br />I heard that a closed water cooling system may not be a good idea on a old engine becouse if there is some build up in the engine it will just clock the heat exchanger.... and more info would be greatly appreicated... thanks Doug

 

[Boatist]

Re: Newbie question Fresh water to salt water conversion

Djohns19<br />Do you know of a source for a full fresh water cooling system (engine and manifold). If you do please share as I have been serching for years with no units found. Does it also protect the Riser??? How long does the heat exchanger last in saltwater???<br />Thanks

 

[24Albie]

Re: Newbie question Fresh water to salt water conversion

Boatist,<br />Do a web search on I-net marine. They sell full and half systems. Before you install the system I would pull the aft casting plugs and use a pressure washer to blow out the sand and sediment that collects in the cooling passages. You'll be surprised how much settles in the block.

 

[Learo2000]

Re: Newbie question Fresh water to salt water conversion

From what I have gathered.. the only system for the 350 cobra/OMC is the half kit.....<br /><br />would you still have to flush the engine after every use then to try and preserve the manifold.......<br /><br />thanks Doug

 

[charleswmoore]

Re: Newbie question Fresh water to salt water conversion

Learo,<br /> I battled this question with my old boat for years. I'll tell you what finally made my decision. Mechanics told me that once the engine is subjected to the salts of raw water cooling for this long then most the damage was done. The process of corrosion had already started even though adding a 50 /50 mix of antifreeze will reduce to continuation of such defects. After a motor has been ran this many years without being pressurized(water jackets) I was afraid that once the kit was installed I would have water squirting out from everywhere so I elected not to take this step. As the other posts mention it is true you can do a full system but even this has drawbacks, 1-risers still need to be raw water to cool exhaust 2- To cool the lower half of manifolds it requires a much larger cooling system and it is hard to seal the riser to manifold joint 100% do to exhaust temperatures and the rusting of risers. Now for my new boat 2001 V/P I ordered the OEM kit that takes care of the block and except the fact that the manifolds are sacrificial. As a final note regarding bottom paint for the first time don't forget to use barrier coats of 2000E prior to applying the bottom paint. The price to paint a 27 eastern the correct way was quoted to me at 1138.00. When it <br />was broken down it seemed resonable. Dry storage looked like a better alternative for me right now.

 

[Learo2000]

Re: Newbie question Fresh water to salt water conversion

Thanks for the info Charles...<br /><br />when you say the salts of Raw water, do you mean salt water... or salts that are found in fresh water as well.. the reason I ask is that this boat has never been in salt water before.. would that make a difference???? Thanks Doug

 

[driftwood47]

Re: Newbie question Fresh water to salt water conversion

Learo2000<br />I have a mercruiser Alpha 1 that I trailer to Norfolk Bay (salt water) and fish. I am careful to flush with fresh water after each trip. I like running in salt water a lot better than freshwater. Mine is raw water cooled(No freshwater cooling system) If the manifolds go- I don't think it is that big a deal. Just remember to flush after each run and enjoy your boat.

 

[Learo2000]

Re: Newbie question Fresh water to salt water conversion

thanks Driftwood... it is going to be moured and the flushing thing would be a bit of a pain in the butt.. although I could do it ..... I like the sounds of the closed water cooling system for many reasons.. but do not want to mess with it if it will casue me more headaches then good.....<br /><br />Doug

 

[charleswmoore]

Re: Newbie question Fresh water to salt water conversion

FLush it every time if you can. My drives have been volvo penta which places the raw water pump on the engine so a simple y valve made this easy.<br />A little creative plumbing and your good to go. If your stern drive package places the pump in the lower unit it is even easier. Install your T in line with raw water intake and let the fresh water supply push the water through instead of the pump. Meaning flush motor without running it.<br />when you do this in this fashion make sure the exhaust port is up out of the water so that the backpressure is minimal so you don't fill up the <br />exhaust cavity and pump the water over the riser back into the cumbustion chamber. There are alot <br />of kits on the market for this application that will retrofit to your application and I would definetly explore them. A five minute fush in a <br />salt water enviroment will add years to the life of your power plant. If your operating in a fresh water enviroment I wouldn't worry about it. But hey all the good fishing in in the salt water?<br />Just another thought.<br />Charlie

 

[Learo2000]

Re: Newbie question Fresh water to salt water conversion

Thanks for the info charles.. I will look into this for sure. I am going to the boat show this weekend so maybe I can find somthing that will work out. IF I understand you correctly, raise the outdrive up so the ehaust is not in the water and attach the house and let it flush.. do this with the engine off?????? thanks Doug

 

[charleswmoore]

Re: Newbie question Fresh water to salt water conversion

Leero,<br /> Yes I would because we rely on the exhaust pressure from the engine running to overcome the back pressue of the stern drive being in the water. (To be sure there is no backflow into the lower exaust cavity of the manifold.) Kind of like putting a water hose into a bucket with only a 2 inch hole. eventually the bucket will over fill provided the volume going in is more than can escape. Also with a stern drive mounted raw water pump, Whenever the engine is running that water has to (needs to) go somewhere. Without this pump turning the water being injected into the T connector should see a backpressure from the impeller and divert the larger amount of volume thru the raw water side of the engine.<br />The devices I see on the market actually close off the water flow back towards the drive pump<br />when you inject water pressure. Also don't forget to have a shutoff valve to your wash out port or you will have quite a bit of water being pumped into boat while running. I saw this type arrangement for sale either in Boaters World or West marine. I'm sure somewone else who is actually in the marine business may or will inject some information that may clarify my beliefs. Take Care Charlie

 

[mattttt25]

Re: Newbie question Fresh water to salt water conversion

learo,<br />i'm planning on doing the bottom paint myself as well. my girlfriend's dad (a seasoned sailor) does all his boats himself. he said it takes light sanding on the bottom, one coat of a primer (about $30/gallon), and one coat of anti-fouling paint (about $150/gallon). he said go high end on the final coat, as it will protect and wear better. he said a gallon of each will be more than enough for my 20 footer. the hard part is getting a good line, gotta put the boat in the water at its heaviest, and mark about 1 inch above waterline. good luck-