525 Motors run in salt water
08-12-2019 | 07:12 PM
#1
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From: Fox Island, WA
525 Motors run in salt water
I like the extra room in the 38 over the 35 but all the 38s I've seen have the 525 motors with the stainless headers. I would love to hear from anyone with 525 motors who run them in salt water. How do you flush them (special products)? How many hours can you expect them to last?
08-12-2019 | 08:24 PM
#2
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From: St-Hyacinthe, quebec, canada
They are closed cool so no flush or better yet still flush the cooler but it wont wear the engine block for sure
exhaust is another story... flush flush and flush is better for exhaust for sure !
exhaust is another story... flush flush and flush is better for exhaust for sure !
08-13-2019 | 07:53 AM
#3
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Joined: Feb 2001
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From: Virginia Beach
This topic has been covered pretty well in the Tech forum. The Merc-spec’d headers are prone to issues. Flush with a lot of fresh water then flush with Salt-Away (do not flush after Salt-Away has been applied). That’ll help some.
Long tail pipe runs also cause issues with cracking due to weight.
Long tail pipe runs also cause issues with cracking due to weight.
08-13-2019 | 03:55 PM
#6
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From: Merritt Island, FL
I am so paranoid I have dawn in one of my containers and salt a way in the other. After 15-18 minutes of water turn both on and let them mix. Run another 5 mins or so. Don't forget to back flush the drives, lots of issues with he small water opening at the transom getting clogged.
My motors are not closed cooled, (HP500EFI)
My motors are not closed cooled, (HP500EFI)
08-15-2019 | 04:34 PM
#8
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From: Long Island, NY
I have a 47 with triple 525's and I run in salt water. My boat is a 2009 and this season I just replaced the headers due to age and wear and it was just time. I flush engines after every use and use Salt-Away. I only flush the engines for a few minutes; that is all that is necessary. My headers also have drains on them and after they cool, I drain them as the last thing I do before closing up the boat. I have been doing this for the past 6 years that I've owned this boat and as I said, just replaced the headers but not because they were leaking. So they have lasted around 350 hours. If cared for, they are fine. The 525EFI also has closed cooling, so the salt water is never entering the engine block; just the raw water cooling passageways.
