Flushing the engine when in the wet stuff

[tinkicker0]

Alternatively get your motor converted to freshwater cooling with an intercooler and associated plumbing, then you don't need to worry about it.

You really need to do this on a new block as the coolant will descale the corrosion already present from salt water use and block up the smaller cooling passages.

I was gobsmacked at the amount of rust scale in my block when changing the water pump last winter

 

[Mymobo]

Gary

I run a 7.4 v8 merc 1995. It has a fitting to allow you to flush the engine when in the water. If you require a pic let me know and I will take one next weekend. But I don't use it. My boat in is salt now and had one manifold done about 3-4 years ago and the other original one last week! So they do last. But I should have done the second one last year. IMHO Mercs are made for salt and unless you plan to keep the boat for a very long time I would not bother with flushing it out and just keep an eye on it. I did ask last week the cost to add indirect cooling and I was told at least £1k.

 

[oGaryo]

Gary

I run a 7.4 v8 merc 1995. It has a fitting to allow you to flush the engine when in the water. If you require a pic let me know and I will take one next weekend. But I don't use it. My boat in is salt now and had one manifold done about 3-4 years ago and the other original one last week! So they do last. But I should have done the second one last year. IMHO Mercs are made for salt and unless you plan to keep the boat for a very long time I would not bother with flushing it out and just keep an eye on it. I did ask last week the cost to add indirect cooling and I was told at least £1k.

thanks, I reckon I'll do the same, the aren't hard to change so will just budget for the event as you say... it'll take a couple of changes to warant the investment and as TK says, it doesn't make an enormous sense to do it now after it's had a few years exposure to salt water

 

[Warpa]

I have been told flushing after every use is not needed, i do it every 2 or 3 months when i trailor the boat home for a bum scrub. The Mercruiser manual says to flush the engine while in the water is done exactly the same as if you did it out of water;

Attach the muffs, turn on the hose, lower the leg and start the engine...all providing you dont have an exdened swim deck and can easily get to the leg (not read every other reply)

 

[rafiki_]

So Gary, does trhis mean that the trade up to a mid '30 footer is on hold for now?

 

[MapisM]

Attach the muffs, turn on the hose, lower the leg and start the engine...all providing you dont have an exdened swim deck and can easily get to the leg (not read every other reply)

Yep, that was my first suggestion in fact.
Btw, it seems to me that the pros/cons of flushing and of closed cooling are being mixed up, whilst they are two completely different things.
The closed cooling is mainly meant to achieve a more stable operating temperature, and in fact it's standard on the most powerful blocks.
It's totally useleff to prevent the salt water corrosion on risers and manifolds, which remain raw water cooled.
'Fiuaskme, I wouldn't bother converting a 5.0 MPI to closed cooling even if it would be a trivial and unexpensive task.
But I'd DEFINITELY flush the leg and engine after every use, if given a chance.

 

[Solitaire]

what I don't know is how do I flush the engine and sterndrive after each trip if the boat's in the water? I am meticulous when it comes to flushing the engine at present and would like to continue to look after it with the same level of dilligence when in the marina... it's a raw water cooled mercruiser 5.0l MPI with alpha 1 gen 2 leg.

There is an option on the market for all engines including outboards.

http://www.superflushsales.co.uk/


It uses an external hose connection and will flush the system in the water.

 

[oGaryo]

So Gary, does trhis mean that the trade up to a mid '30 footer is on hold for now?

it is mate, house extension, job change and a few other factors will see us keep hold of Lorn Jane for another season I reckon... we've still decided to move to a marina though as we're not getting full use of the boat at present.. 2.5 hour drive, plus launcing in a yidal slip = too much hassle

 

[oGaryo]

There is an option on the market for all engines including outboards.

http://www.superflushsales.co.uk/


It uses an external hose connection and will flush the system in the water.

that looks more like a cost effective solution... will drop in and see them next time we're down there

 

[oGaryo]

Yep, that was my first suggestion in fact.
Btw, it seems to me that the pros/cons of flushing and of closed cooling are being mixed up, whilst they are two completely different things.
The closed cooling is mainly meant to achieve a more stable operating temperature, and in fact it's standard on the most powerful blocks.
It's totally useleff to prevent the salt water corrosion on risers and manifolds, which remain raw water cooled.
'Fiuaskme, I wouldn't bother converting a 5.0 MPI to closed cooling even if it would be a trivial and unexpensive task.
But I'd DEFINITELY flush the leg and engine after every use, if given a chance.

I reckon the swom platform's going to be restictive to get the muffs on safely... thanks for the info regarding the risers still being flushed with salt water, makes the closed system useless for my needs in that case

 

[rafiki_]

Gary, I don't think you need worry too much about the flush. Given that number of V8's you see in Florida, and I guess the sea water is just as salty there, you will be ok. If I remember my chemmy from school, there will be less corrosion if the parts remain under water, as there will not be much O2 to help the reaction.

 

[oGaryo]

Gary, I don't think you need worry too much about the flush. Given that number of V8's you see in Florida, and I guess the sea water is just as salty there, you will be ok. If I remember my chemmy from school, there will be less corrosion if the parts remain under water, as there will not be much O2 to help the reaction.

I recall the same, something about black rust only turned red when exposed to air... ?

 

[rafiki_]

Yes, think so. Just enjoy the added convenience of the mooring, and stop mithering!!

 

[oGaryo]

Yes, think so. Just enjoy the added convenience of the mooring, and stop mithering!!

sorry dad

 

[rafiki_]

sorry dad

Hey, enuff of your cheek m'lad!