JVM225
Well-Known Member
The original motors in my old boat were 25 years old when I decided to re-power. They were RWC and used exclusively in saltwater for all of their lives.
Raw water cooled engines in salt water
- Thread starter majoma
- Start date
The original motors in my old boat were 25 years old when I decided to re-power. They were RWC and used exclusively in saltwater for all of their lives.
scoflaw
Well-Known Member
- Aug 10, 2011
- 6,395
- Boat Info
- 1999 Powerquest legend 260 sx 502 mag
2005 Baja 242 islander 496
- Engines
- 502 mpi Bravo 1
496 mag B1
Some people just don't seem to understand how salt water reacts with iron. Once it gets dipped, you can flush it all you want and it will still rust. It's called electrolysis.
El Capitan
Well-Known Member
- Jul 9, 2014
- 3,828
- Boat Info
- 1970 SRV 180 w 2.5L Mercruiser.
2000 Ford Expedition Eddie Bauer
- Engines
- 120HP Mercruiser
Exactly. The inmates here ignore the realities of salt water corrosion on ALL systems.
I love the the guy that says " I've got two 7.4's in salt and they run like the day they were new". LMAO. Denial is obvious here.
Yet you'll note the resale values of salty boats vs "never used in salt water" or "100% freshwater boat".
majoma
Member
Has anyone use a product called Salt-Away to flush the engines?
NotHerDecision
Well-Known Member
- Jun 28, 2016
- 2,173
- Boat Info
- 2001 Sea Ray 460 Sundancer
2014 Seadoo 155 LTD
2105 Seadoo 130 SE
2013 Mercury Dinghy
- Engines
- Cummins 6CTA 8.3L
I use it every time we take out our 2 seadoo's. works amazing. I even have a sprayer and it cleans the salt off the exterior of them.
Sent from my iPhone using Tapatalk
Sent from my iPhone using Tapatalk
RollerCoastr
Well-Known Member
- Nov 15, 2007
- 3,884
- Boat Info
- 1997 400DA
340HP 7.4 Mercruiser Bluewaters
Garmin 741, 742, 8212, 24HD, Intellian I2
- Engines
- 1999 280BR
Twin 250HP Merc 350 Alpha Ones
"Boating is fun!" "Great day on the water!!" "We just need to flush the engines and we can go home"
"Google says SB traffic on I-95 is at a stand-still." "US1 is gridlocked from 858 to ---SMACK was that a no-see-um?-- to 195 ---SMACK, yes I think it SMACK was---" "Are these damn ---SMACK--- engines done SMACK yet" "that jerk just ran over the hose and now --SMACK--- it's spraying all over the parking --SMACK--- lot" "The dog just pooped behind ---SMACK--- that SUV over there..." "Stop pouting, you can ---SMACK--- charge your phone when we get into the car, we just need to do the other engine...."
Salt in engines is fun. (no quotes, because that has never been said)
"Google says SB traffic on I-95 is at a stand-still." "US1 is gridlocked from 858 to ---SMACK was that a no-see-um?-- to 195 ---SMACK, yes I think it SMACK was---" "Are these damn ---SMACK--- engines done SMACK yet" "that jerk just ran over the hose and now --SMACK--- it's spraying all over the parking --SMACK--- lot" "The dog just pooped behind ---SMACK--- that SUV over there..." "Stop pouting, you can ---SMACK--- charge your phone when we get into the car, we just need to do the other engine...."
Salt in engines is fun. (no quotes, because that has never been said)
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mobocracy
Active Member
I don't have a dog in this fight, but I'm curious. Obviously raw water cooling has been around a long time and still very common on lots of new boats. If it was instantly destructive, I would have expected it to have gone away. Obviously it has a corrosive quality to it in salt water but manufacturers have adapted with improved coatings to resist corrosion. And engines and their components have a finite wear life anyway, so even if you never had a corrosion problem the engine would wear out eventually anyway, although obviously salt water will accelerate this somewhat.
As for resale values, do these represent the inability of any raw water cooled engine to last in salt water, regardless of care, or does it represent the nominal increased wear of salt water combined with the uncertainty of how well cared for a random boat for sale really was?
I guess my question boils down to is if a 5 year old freshwater engine that is well, but not exceptionally, maintained has 80% useful life remaining (I just made that number up for argument's sake), what are the values for a saltwater engine that is exceptionally maintained? Well maintained, but not exceptionally?
I've had brokers tell me roughly 15% price difference between fresh and saltwater boats of the same make, which would mean that minus market uncertainty (ie, is the seller a liar), the useful life difference of a very well maintained salt water engine and a freshwater engine shouldn't be that much.
Boater420
Well-Known Member
- Mar 11, 2015
- 1,259
- Boat Info
- '97 330 Sundancer
V-Drives
Westerbeke 4.5BCG
- Engines
- Twin Merc 454's
The 7.4's in my boat still reach WOT, still cruise at the same speed, still have good compression across all cylinders and the oil samples came back clean when I purchased the boat, so what am I missing? They still idle well, and cool properly so where am I going wrong in my assumption that they still perform like when new? Just not seeing the denial I guess??
dpmulvey
Active Member
- Dec 19, 2007
- 4,188
- Boat Info
- 1999/2007 330 Sundancer Hardtop.
- Engines
- 6.2 Merc Horixons
1.5:1 Velvet Drives
I thought electrolysis had something to do with electricity in the equation somewhere. Stray grounds or something.
scoflaw
Well-Known Member
- Aug 10, 2011
- 6,395
- Boat Info
- 1999 Powerquest legend 260 sx 502 mag
2005 Baja 242 islander 496
- Engines
- 502 mpi Bravo 1
496 mag B1
There is a small amount of electricity in the make up of iron , in its electrons.
JVM225
Well-Known Member
I recently came off a year of shopping for a boat and had the opportunity to look at both salt water and fresh water boats while looking for the 410 that we ultimately bought a few months ago. After looking at more 03-04 380's and 01-02 410's over the past year than I care to remember I can say that owner maintenance was a huge factor in the overall condition of boats and whether they were in salt water or fresh water had little to no impact on what shape these early 2000's boats were in.
There were as many poorly maintained fresh water pigs in the mix as salt water boats, and there were as many really nice saltwater boats as there were fresh water boats. The 410 we wound up with is a well maintained saltwater boat in fantastic condition. Much nicer than several fresh water boats we looked at.
Maintenance and regular cleaning are way more important on a used boat than the type of water it has been used in.
BTW: here is a couple of shots of my then 29 year old saltwater boat I sold last June shortly before we parted with her. First shot is of the boat while I'm waiting for the boat hauler to come load her up for launch last Spring, the second is a close up of the finish on the then 29 year old hull, and the last is to illustrate the condition of the original teak in the cockpit that I always lovingly maintained. I'll put it up against a fresh water boat half it's age for condition anytime:
There were as many poorly maintained fresh water pigs in the mix as salt water boats, and there were as many really nice saltwater boats as there were fresh water boats. The 410 we wound up with is a well maintained saltwater boat in fantastic condition. Much nicer than several fresh water boats we looked at.
Maintenance and regular cleaning are way more important on a used boat than the type of water it has been used in.
BTW: here is a couple of shots of my then 29 year old saltwater boat I sold last June shortly before we parted with her. First shot is of the boat while I'm waiting for the boat hauler to come load her up for launch last Spring, the second is a close up of the finish on the then 29 year old hull, and the last is to illustrate the condition of the original teak in the cockpit that I always lovingly maintained. I'll put it up against a fresh water boat half it's age for condition anytime:
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scoflaw
Well-Known Member
- Aug 10, 2011
- 6,395
- Boat Info
- 1999 Powerquest legend 260 sx 502 mag
2005 Baja 242 islander 496
- Engines
- 502 mpi Bravo 1
496 mag B1
I recently came off a year of shopping for a boat and had the opportunity to look at both salt water and fresh water boats while looking for the 410 that we ultimately bought a few months ago. After looking at more 03-04 380's and 01-02 410's over the past year than I care to remember I can say that owner maintenance was a huge factor in the overall condition of boats and whether they were in salt water or fresh water had little to no impact on what shape these early 2000's boats were in.
There were as many poorly maintained fresh water pigs in the mix as salt water boats, and there were as many really nice saltwater boats as there were fresh water boats. The 410 we wound up with is a well maintained saltwater boat in fantastic condition. Much nicer than several fresh water boats we looked at.
Maintenance and regular cleaning are way more important on a used boat than the type of water it has been used in.
BTW: here is a couple of shots of my then 29 year old saltwater boat I sold last June shortly before we parted with her. First shot is of the boat while I'm waiting for the boat hauler to come load her up for launch last Spring, the second is a close up of the finish on the then 29 year old hull, and the last is to illustrate the condition of the original teak in the cockpit that I always lovingly maintained. I'll put it up against a fresh water boat half it's age for condition anytime:
Seeing this post is now 4 pages long, you may have missed post #1, where the OP is wondering about closed vs. raw water cooled engine in a salt water environment.
- Mar 8, 2012
- 220
- Boat Info
- 350 Sundancer Coupe 2020
Prior
310 Sundancer 2015
- Engines
- Dual Horizon 8.2 V Drive
The really big issue is maintenance. If you are RWC, you are looking at swapping out the Manifolds plus risers ever 5 years vs. a FWC where you are going to be swapping the risers only (but I have read you need to check the manifolds just to ensure they are not damaged) every 5 years, so that is a difference in $$. The bigger maintenance issue in either engine is the stern drive which from my experience winds up costing more to maintain. Now not scientific in nature, my neighbor with an 80's 300 Sundancer replaced both motors and stern drives at about 20 years. Another neighbor with a late 80-90's 300 or 320 (not sure if I remember the exact size) has the same engine but it is FWC with V-drives. Overall I would pick the best maintained boat and skip stern drives if you can. It is kinda hard because from 260-330 Sundancer right now come with stern drives only.
Dave
Dave
JVM225
Well-Known Member
No, I didn't miss anything. The purpose of posting images was to make the point that maintenance is more important than environment when shopping for a used boat.
Sorry if the pictures annoyed or alarmed you.
scoflaw
Well-Known Member
- Aug 10, 2011
- 6,395
- Boat Info
- 1999 Powerquest legend 260 sx 502 mag
2005 Baja 242 islander 496
- Engines
- 502 mpi Bravo 1
496 mag B1
You forgot to post the pics of the inside of your iron block and heads. That is the topic if you forgot
majoma
Member
Well, after all of your comments, I am more confused than when I started, but it makes sense that a fresh water cooled engine should be a better option.
JVM225
Well-Known Member
It may well be, but I wouldn't make it the main criteria. Take in to consideration the individual boats overall condition. If you just dismiss salt water boats you may be passing up on some real nice stuff.
TitanTn
Active Member
- Jul 12, 2015
- 386
- Boat Info
- 1986 Saltare, 1998 400 Express
- Engines
- 454 direct drive; twin 3116TA
I think your post was very relevant and helpful. Thanks for posting the pics and bringing the maintenance consideration to the discussion.
