Print Page | Close Window

Chev 350 vs Ford 351 for salt water?

Printed From: CorrectCraftFan.com
Category: General Correct Craft Discussion
Forum Name: General Discussion
Forum Discription: Anything Correct Craft
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=39354
Printed Date: May-03-2024 at 1:34am


Topic: Chev 350 vs Ford 351 for salt water?
Posted By: 1xsculler
Subject: Chev 350 vs Ford 351 for salt water?
Date Posted: July-17-2016 at 3:26pm
I have heard that the PCM Ford 351 Windsor marine block, if there is a special marine block, will last much longer with salt water running through it than a PCM 350 Chevy block will last. Is that true? Did/does Ford make a 351 marine block different from their standard 351?

I have run my 1994 Ski Nautique with the 351 exclusively in salt water flushing it with fresh water only at the beginning of the season in May and again when I take it out in October and the block is doing very well so far. I have installed new exhaust manifolds twice since 1994 just as a precaution. I'm wondering how many more seasons I can expect out of my '94 block before it rusts through.



Replies:
Posted By: peter1234
Date Posted: July-17-2016 at 3:34pm
I would imagine it comes down to the salt content.. Why is it that you dont flush it with each use?   For me its easy my boat is docked in a fresh water river and its 6 miles to salt so the return trip clears it .

-------------
former skylark owner now a formula but I cant let this place go


Posted By: 1xsculler
Date Posted: July-17-2016 at 5:41pm
I knew I was going to hang this boat on a buoy in front of our Puget Sound home in a situation where it would be nearly impossible to flush it out after each use SO I asked a lot of questions of a lot of Puget Sound boaters and I learned that while some people did spring for fresh water cooling the vast majority of inboard boats which lived in the salt water year round ran salt water through their cast iron blocks and heads and never flushed them ever. I found that hard to believe at first but became convinced the more I looked into it. I concluded that if all of these yachts' engines survived mine would too so I went ahead and purchased our Nautique and have had nearly zero problems ever since.

Is there such a thing as a "Marine" Ford 351 Windsor or a "Marine" 350 Chevy block which I'm assuming would be thicker in the water jacket areas?

Do 351 Ws have a reputation of lasting longer in salt water than the 350s? I'm pretty sure the aluminum heads, which I think come on the GT 40s are a bad idea in salt water.


Posted By: DayTony
Date Posted: July-17-2016 at 6:35pm
I would say no on the aluminum heads.
And salt content really isn't as much a factor of how bad the electrolysis is If you have only put two sets of manifolds on it in the last 20 years your doing much better than it would here in salem sound.

to answer your question, no. there is no special marine block that will last you longer. you could get an aftermarket block like a Dart block which has a lot thicker cyl walls and some extra ribbing to stiffen up the main line but it would be throwing away a lot of money really fast to not spend another thousand and make it fresh water cooled. Its really not that complicated to do and its great piece of mind. but for the price of that block you can build almost a whole motor.
It already sounds like your prepared to drop a lot of coin to refresh the boat And you've asked which is going to last longer because you obviously care, and want to do the right thing. and the right thing would be a closed cooling system.

-------------
1988 Barefoot nautique-454


Posted By: Gary S
Date Posted: July-17-2016 at 11:25pm
I know South Florida waters are tough and seem to be way worse than northern waters. Dads PCM powered boat was on it's 3rd set of exhausts in 20 years,along with 1 upper thermostat housing. Never spent the night in the water and flushed after each use,in use from November to April.
Here is a picture of a PCM Ford intake manifold in use from 78-93 in south florida when we bought it. No idea on flushing but I'm guessing not often. I went to reuse this but decided against it since there not much sealing surface left. This is looking into the water passage with the temp boss in the back ground. I think Ford blocks will be available due to the shear number of them being made. What will be troublesome is intakes,thermostat housings,timing covers etc.



-------------
http://www.correctcraftfan.com/diaries/details.asp?ID=1711&sort=&pagenum=1&yrstart=1966&yrend=1970" rel="nofollow - 69 Mustang HM SS
95 Nautique Super Sport


Posted By: TRBenj
Date Posted: July-18-2016 at 12:47am
Marine blocks aren't special and GT40 heads aren't aluminum.



Print Page | Close Window