outboard+saltwater question

[mla2ofus]

Re: outboard+saltwater question

The previous post is why I advocate, as i did above, that you actually take it to a freshwater river or lake to flush it out. Often times the engine just won't get hot enough on the hose to allow the t-stat to open up and really flush the whole mess. I know that launching in a river and running down tot he salt is not always an option, although it is the best option, IMHO, but a 15 minute run in your local lake will wash it out clean-like. Just make sure you're not transporting invasive species between the two bodies of water, please.

That's why I originally asked about using the flush plug w/ a hose as I have to remove the motor and stick it in my test barrel to flush it if I don't launch it in fresh water.
Mike

 

[Home Cookin']

Re: outboard+saltwater question

thanks, elchrisam; hadn't seen that before but I don't look inside a lot of motors anyway. i wonder if my old 20 hp merc is that way?

As to flushing, it seems to me that when you shut down the motor, the water drains out, but the salt water quickly dries on the surfaces, and does its think. Once it has dried, it seems to me, flushing is not going to remove much, if any, of what has dried on the surface and started its work. Thus the pitting simply compounds. And while I know the pitting is worse as salinity increases, I'd be interested to know the extent of pitting from lake/river water? In other words, will a 20 year old motor show some amount of pitting regardless?
I remember a long time ago (1970's) learning that OMC changed its headgasket material, resulting in more headgasket failure from the salt, so I'm sure there are parts other than the interior that benefit from flushing, too. Nonetheless, many salties go through long lives with no flushing--it's a relatively new procedure (in my 45+ years boating).

 

[elchrisam]

Re: outboard+saltwater question

thanks, elchrisam; hadn't seen that before but I don't look inside a lot of motors anyway. i wonder if my old 20 hp merc is that way?

As to flushing, it seems to me that when you shut down the motor, the water drains out, but the salt water quickly dries on the surfaces, and does its think. Once it has dried, it seems to me, flushing is not going to remove much, if any, of what has dried on the surface and started its work. Thus the pitting simply compounds. And while I know the pitting is worse as salinity increases, I'd be interested to know the extent of pitting from lake/river water? In other words, will a 20 year old motor show some amount of pitting regardless?
I remember a long time ago (1970's) learning that OMC changed its headgasket material, resulting in more headgasket failure from the salt, so I'm sure there are parts other than the interior that benefit from flushing, too. Nonetheless, many salties go through long lives with no flushing--it's a relatively new procedure (in my 45+ years boating).

HI Home Cookin, I just purchased a 35 hp Merc 1964 (Look at my other post) It has run all it's life in a Loch. When you look at the waterway casing there is no white deposits on edges, so I assume that it will be ok. The one above was showing white deposits on the water jacket edges, which is the main reason why I took it apart. I think the only way to tell is remove a water jacket cover, but if salt has got in the bolts will shear like the ones on the merc above. 8 bolts, 4 sheard, it took about 16 times welding nuts to the stuck studs until I got them out. Maybe it would be better to not know! chris

 

[kahuna123]

Re: outboard+saltwater question

My Dad ran a 10 Johnson for 30 years twice a week in salt. Brought it home in a barrel and ran it. Never had an issue. The Yamaha 15 was so clogged that I could not get it to not overheat above half throttle. Finally pulled it apart (sheered 3 headbolts) and had to scrape the salt out with a screwdriver. Completely full. Yes the barrel or the muffs will work but you gotta warm it up. At least in the barrel you can put it in gear and force it to warm up. Also the water in the barrel will eventually get warm and help. Anymore on the little kickers we use on small boats I am pulling the thermostats out. The Yamaha had the new style hose attachment and ran out of gear spitting water all the time but never circulating the head. Dang shame, it sat 10 years and still started the first pull. Looked brand new. Now it needs a 500 block.

I was with a rep from one of the outboard manufacturers on a new install. My first question was muffs or the hose attachment. He said well, the hose way does go through the head but it bypasses the water pump. Go figure.

 

[Home Cookin']

Re: outboard+saltwater question

As between the Yamaha hose attachment and the muffs, I go for the muffs for the reason you stated. Frankly, I'm more concerned about washing off the impeller (high salt eats it up) and any silt/sand down there before it cakes up.

let me ask you all this about warming up--when I do flush, I am at a private ramp so I flush it right there when I pull the boat out, usually within 30 minutes of running it, although sometimes in winter after running in 40* water. Flush with well water so that's probably 55 in the winter. Can I assume that the engine is still warm enough to get some of that benefit?

 

[V153]

Re: outboard+saltwater question

Glad someone mentioned well water. Our little one holer Civic Assocation ramp has a well fed rinse down station. Some would tell you that stuff is worse than salt water but I dunno. Guess they're right in a way cuz it's got everything but salt in it. Iron, sulphur, tannin, etc etc. Granpappy Jack always called it 'lumpy water'. But it hasn't hurt any of my boats yet?

Hey not trying to be a smart a** but how does this hose attatchment thingy flush the motor whilst 'bypassing' the water pump. Isn't the water pump what pushes the coolant? And shouldn't the pump have water in it when the motor is running? Please advise.

 

[Home Cookin']

Re: outboard+saltwater question

you don't run the motor with the built-in hose attachment--but lots of people don't know that. I suspect enough water trickles down there to lubricate enough to be lucky but probably not. It won't hurt the engine itself; the guy I bought mine from didn't know, so I just replaced the water pump before I splashed the boat.
When hooked to the hose, the water pressure from the hose fills the water jacket, etc. This is why I question the notion that any flushing created enough scouring pressure to remove what is already there from ordinaty use. It just replaces the left-over salt water with fresh.

As for wells, obviously it all depends, but except in an extreme situation (like the "bore" water in the Nullabor, W. Australia!), how can it be that different from the lake, river or bay you run in all day?

However, those who use the treated city water find 80% fewer cavities in their motors.