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crusader engines going into salt water

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davidandjudy

New member
we plan to take our 1986 Carver with 350 crusaders into salt water next year. now equipped with lake water cooling. what should we do to protect the engine. are there conversion kits for a closed loop system? do we simply need some sort of fresh water flush system? or doesn't it make much difference. any help and advice apapreciated.

david and judy
 
Are you doing one trip into salt, or permanently staying in salt water? Some time ago, I had a OMC 305 raw water cooled. After each trip I flushed the engine and in the 6 years I had that boat never had a problem, except the oil pan rusted once in mid summer, a small hole.
 
There are many who feel that fresh water flushing engines after use in salt water does not increase the life of manifolds, elbows, etc.
Nightstalker
 
Your power plants are over 25 years old. I'd be inclined to use-as-is and consider FWC if you plan to overhaul or upgrade. I don't believe converting them now makes sense, economically.
 
bulletine said:
Are you doing one trip into salt, or permanently staying in salt water? Some time ago, I had a OMC 305 raw water cooled. After each trip I flushed the engine and in the 6 years I had that boat never had a problem, except the oil pan rusted once in mid summer, a small hole.
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thank you for your comments. the boat probably will be in salt water for at least several years. we may leave it in florida as a winter haven, and perhaps eventually sell it there.

how did you flush the engines after each trip with fresh water. some hose attachment, or did you return to fresh water and just run the engines there?

thanks

david
 
Running back through fresh water to your moorage would be best, if that's an option.
Otherwise, there are some potable water flushing kits that can be installed.

For me, the trick will be in turning off the water supply just prior to shutting the engines down... yet preventing additional salt water from entering the system.
3 - 4 seconds of impeller run is not a deal breaker!

.
 
Meant to say this flush device can take in water that may be in the bilge, then I believe it goes into the raw water system and out.
 
Nothing wrong with running in salt water. Flushing not necessary. My boat 1966 Californian twin 350 crusaders. Raw water cooled completly. No loop system, no exchangers just raw salt water in, thru the engines and out. Ive owned her for 7 years now. Replaced both manifolds 1 1/2 years ago just because they were on before I owned the boat and for piece of mind. I run the engines twice a week for about 20min just to keep the water in the jackets fresh. Never heats up runs really well. Unknown hrs on the engines. Remember engines love to run not sit for longggggggg times.
 
I would love to see a picture of the inside of that engine with the heads pulled some day. My last boat was a 30 pacemaker with 350ci crusaders raw water cooled, the engines were rebuilt in 2004 and I have always flushed them after use. I just sold that boat in July and the the temps on both engines never went above 145. That's 7 years on the exhaust system and I believe the flushing had a lot to do with it. I've seen some salt water engines taken apart for a rebuild and they were so corroded and eaten away that they had to be scrapped. I just don't think it's ever a good idea to leave metal sitting with salt water in it for any period of time wether the water has just been flushed thru or it's 2 weeks old, it is a very highly corrosive liquid and when you boil it in the water jackets it becomes even more so. If there truly wasn't a difference between fresh and salt water you can bet the first ones to get rid of the fresh water systems would be the manufacturers, they don't like to spend money when they feel it isn't absolutely necessary. Also , there's a book written by David Pascoe,the surveyor, that quotes him as saying that a fresh water cooled engine will last twice as long as a raw water cooled one. It's a great read if you're looking to solve some problems. The last thing I want to do is cause a ripple, but I just whole heartedly disagree with the first lines of the last statement.
 
Change thermostat to 140 degrees. Much above that will cause salt in water to crystallize.

I have found fresh water flushing after each use prolongs life of elbows, which along with heat exchangers is only parts of my engines that are raw-water cooled. I have tees in water lines between seacocks & pumps to do this.
 
leokow said:
I would love to see a picture of the inside of that engine with the heads pulled some day.................
I've seen some salt water engines taken apart for a rebuild and they were so corroded and eaten away that they had to be scrapped. I just don't think it's ever a good idea to leave metal sitting with salt water in it for any period of time wether the water has just been flushed thru or it's 2 weeks old, it is a very highly corrosive liquid and when you boil it in the water jackets it becomes even more so. If there truly wasn't a difference between fresh and salt water you can bet the first ones to get rid of the fresh water systems would be the manufacturers, they don't like to spend money when they feel it isn't absolutely necessary. Also , there's a book written by David Pascoe,the surveyor, that quotes him as saying that a fresh water cooled engine will last twice as long as a raw water cooled one. It's a great read if you're looking to solve some problems. .............
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I'm with Jeff and leokow on this....... Ditto!

Until you've pulled a salt water engine down, and have looked closely at/into the water jackets, you just don't know how destructive salt water can be, and/or just how much iron material has been compromized.

No way in Hell would I ever over-haul a previously Salt Water cooled engine..... not when we're only a few dollars away from automotive cores that have only seen E/G coolant their entire lives.

Been there/did that... ONCE.... and a long time ago......., and once is all it takes.
On a .030" over-bore, the boring tool poked right through a cylinder wall that had been subject to randem corrosion effects.
Mind us, a .030" over-bore is only .015" off the wall.
Corrosion within an engine block takes randem paths.... there is no way of predicting this path.

What if that boring tool had NOT penetrated the cylinder wall, and had been shy of only .040" of penetration, leaving us to think that all was A-OK???? :mad:

Not worth the risk, IMO.

.
 
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Since we kind of drifted around on your question and left room for some confusion I thought I'd bring the consenus to you in plain english. Looks like the majority of us concur on the idea that flushing engines used in salt water is the next best thing to having them fresh water cooled. The connectors that BULLETINE recommended a few post up are a fantastic way to accomplish this. It puts a brass fitting into the raw water line with an adapter for connecting a fresh water hose too. Perko also makes one but it's made from some type of acrylic and I don't get that warm and fuzzy feeling having plastic in the main water line for cooling the engines where a crack or break would deprive the engine of cooling, besides the brass ones are less money . They cost me about $85 a piece and I use them to flush the salt water side of my cooling system anytime I'm not going to use the boat for an extended period of time and it also makes winterizing a lot easier for me. That closed loop system that you mentioned would run you close to $1500, plus labor and like the rest of the guys I don't think it would be a prudent use of money at this stage of your engines' life. I doubt if you'll be needing anti-freeze in Florida so your only concern would be cleansing the engine of salt water after using the boat, just remember to shut the boat down BEFORE you turn the water off or you'll be sucking salt water right back in again. Good luck on your trip...Lee
 
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I successfully converted a Chrysler 440 from raw to closed cooling, it was maybe 15 years old at the time. A lot of the bolt-on water components were a scaly/rusty mess, but somehow the bock was OK. It was a southern ocean boat motor, but ran a fairly long distance in a brackish to mostly fresh water canal on the way back home. I did a major OH on the motor, including an acid dip of the block.
If you love the boat, and want to keep it for some time, AND the engine(s) are very healthy, I'd advocate the conversion. But note that for the nearly $2000 for conversion, you can buy used 454 closed circuit motors as pullouts. I tend to think that it takes a lot of flushing and/or running in fresh water often to keep a salt rw motor from scaling up internally.
 
Dave....I could see spending the funds for the conversion if the motors were only 15 years old but at over 25 I think it wouldn't be a very prudent expenditure of those funds. The last boat I had was a 30' pacemaker with 350 crusaders raw water cooled, rebuilt in 2004 and I only flushed them for about 5 minutes each, but I did it every time I used the boat and the new owner does the same, he tells me she still runs at 140*. I think that considering the age of these engines investing $200 and flushing them after each use would be the way to go, However..in the long run , I guess it's just a matter of choice. Good luck to them , whatever they decide.....Lee
 
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