adding closed cooling

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Brite Idea

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I bought a boat in August from Missouri, fresh water ten years 250 hours. The 5.0's are catalyzed so it ups the cost. I can install closed cooling for about 10K. I know it's expensive but the long term benefits outweigh the cost.
My question to you guys is it really worth it or should I just install Perko flush kits?
 
10k is probably the cost of changing risers and manifolds at least twice. So Break even point would be a minimum of 10 years. I don’t think it’s worth it
 
Me...I'd just go with the flush kitsa. Also, they make it easy to winterize.
 
quote:
Originally posted by cwms

Me...I'd just go with the flush kitsa. Also, they make it easy to winterize.

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+1
 
Wow you guys are great! I appreciate the quick responses. Here's what I left out, the closed cooling systems are full systems so the manifolds become part of the closed cooling. Also the engines are 5.0EC which means they have the catalytic converters and manifolds are much more expensive to replace. The closed cooling systems are only available thru Mercruiser because of the catalytic converters and ECM replacement is included, no after market systems available. The pro's & cons have been bouncing around in my head since I took delivery in August. My last boat bought the same way and installed the closed cooling worked out well but was much more affordable.
 
My opinion it’s not even close to worth the cost to convert. In addition to the flush kits and changing the risers & manifolds, I think it’s most important to examine often for any leaks, and I’ve found I need to replace gaskets about twice as often as the iron parts. Keep the gaskets fresh, parts properly torqued, flush often, you should be able to get respectable life in saltwater.

Only motor that ever failed on me due to salt corrosion was due to leaking exhaust manifold gasket, that I was not aware of until is was too late. It’s a pain, but every other year I pull the manifolds off, replace all of the gaskets, and check for damage.
 
The other thing to think of is how long would you plan to own that boat? My experience with cast iron engine/raw water cooling here in Long Island is that you can easily get 10-15 years on the engine, before you might have issues with rust through; it seems most often with intake manifold right under the thermostat housing or cyl heads behind the valve seats. Exhaust manifolds & elbows need checking & often replacing at the 5-7 year mark or sooner if leaks are noticed around the gasket between the manifold and elbows.
 
You didn't say if you boat in fresh or salt water? My boat spent the first 10 years of it's life in fresh water and was raw water cooled. i did a full system conversion when I moved to the Chesapeake bay and don't regret it. Now, I just change the elbows every five years. I did replace the antifreeze in the block very early on as it brought a lot of river crud out of the blocks. If I had to do it again, i would but I might just run distilled water in the blocks for the first few hours.
 
Boat came from Lake of the Ozarks and is now in salt water. I'm leaning towards biting the Bullitt and doing it. I would have jumped on it and done it myself but having to change out the ECM's made me re-think that since I'd like to cover the work with a warranty! My last boat I did it and never regretted it but it was way less expensive.
 
I agree that closed cooling is really desirable here in Long Island salt water, it makes winterizing easier and adds resale down the road. If you have inboards or I/Os two things you really want is closed cooling and a remote oil filter mount, that makes the regular maintenance a good deal more tolerable. Every year when I winterize my boat I think of how nice it would be not to have to take out half the rear seat to get at the engine drains and standard mount oil filter. If I repower this boat with a new or reman engine for sure I will add both.
 
quote:
Originally posted by CaptCrunch

10k is probably the cost of changing risers and manifolds at least twice. So Break even point would be a minimum of 10 years. I don’t think it’s worth it

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actually if you price it out, replacing the manifolds + elbows on a cat converter engine, just once can be 4500-5000. So for twins that's close to 10 grand for one change of manifolds and elbows. I'd hope that they last longer than the non-cat systems here we usually replace at about 7 years.
Personally I'd never buy an EFI boat with cat converter exhaust. The cost factor here in salt water makes outboard parts prices seem reasonable lol.
Any inboard boats I own the rest of my boating days will have simple carbed engines and standard exhaust. That, or outboards.
 
The newer engine packages with the emission controls are not desirable and this will be my last I/O boat. If we go bigger like the 340 Sundancer(v-drives) or the 290 Coastal(outboards) I can say good bye to I/O's. I'll post my final decision once I finish my cost analysis.
 
So I did end up having the closed cooling installed and the results are the engines are running cooler and also fuel economy seems better. I think long term it has been a good decision. Winterizing will be easier also.
 
You should look into selling the old parts on eBay to recoup some of your costs.
 
thanks for the update. When I converted my 454 Crusaders 10 years ago, the cost was about half what you stated in the first post. I didn't have many parts other than the original thermostat housings and a few elbows left over after the change. Didn't think worth selling.
 
Brite Idea said:
So I did end up having the closed cooling installed and the results are the engines are running cooler and also fuel economy seems better. I think long term it has been a good decision. Winterizing will be easier also.
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The engines are running cooler? How much cooler? I could be mistaken, but my recollection is that antifreeze cooled motors are able to run 15 or 20 degrees HOTTER than seawater cooled which is more efficient and less wear on the motors. May want to confirm you have the correct thermostat in there, and are not running at rwc temp.
 
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Definitely agree with you as I thought the engines would run hotter but previously they ran at 175 but now are at 160. I had it done by a Mercruiser shop I've used for twenty years and trust completely so he said it's where it should be so "That is That" as they say. Maybe it has something to do with volume of water since now the cooling raw water is pulled from a thru hull as opposed to pulling it thru the drive?
 
I guess you were just running hot before ( or had wrong thermostat). 160 thermostats seem to be the norm for antifreeze cooled mercruisers. 135-140 for sea water cooled.

i gave up years ago on pulling water through the drive - and put a scoop on the transom. After years of battling temp issues, never another problem. one of the best upgrades I ever did. but I do worry about not having cool water pumped through the drive. I put a drive shower on, hoping that would help. Did your shop have any concerns about blocking the drive intake? Merc does sell the block off plate for the transom, and all of the performance boats get their cooling elsewhere - but I remember at the time being warned I would shorten the life of my drive.
 
The water passage has been blocked off and the hose that runs from the drive to the transom assembly has been cut. Drive showers will be added this winter. The Bravoitis fix is a thru hull water pickup and should really be the only way they're manufactured.
 
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