Outboards after saltwater use

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klee wyck

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Looking for suggested protocols for care of tender outboards after use in saltwater. Please describe what has given good results for yours in terms of longevity and service. (Recovering from expensive repair resulting from apparent inadequate care.)
 
I rinse mine and run it out of fuel.when I have access to fresh water other than water tanks.
 
I rinse mine and run it out of fuel.when I have access to fresh water other than water tanks.

+1

I use the "ear muffs" that allow you to do a fresh water flush. With 600 gal on board and a faucet on deck I sometimes do it before I get back to the dock :socool:. At the same time as the flush I disconnect the fuel hose and run the carburetor dry until the motor stalls.

Richard
 
Never done anything, just run it. If its gonna set awhile I run some Stabil thru it. I really dont like running a two stroke out of gas (oil?) but a lot of folks do it. I have flushed a few with Muratic or similar, especially if overheating was a problem. Changed lots of thermostats.
 
We run all our outboards, 2-cycle and 4-cycle, on non-ethanol fuel (as we do with our lawnmower, home generator, etc.) That alone make a huge difference in the reliability and longevity of the motor in terms of running properly.

While we are on a cruise or have our outboard trailer boat up north on a fishing trip, we do not flush the dinghy or fishing boat motors or run them out of fuel during the duration of the trip.

But after the longer trip, or after using the cruising boat's dinghy or the fishing boat down here for a day or two when the motors are then going to sit for a few weeks or more before we use them again, we ALWAYS run them on fresh water, using the ear-muff attachment on the large motor on the fishing boat and the screw-in hose adapter on the dinghy and trolling motors for a good ten or fifteen minutes at medium idle speed (per the manuals). This is long enough to let the thermostats open and let water through the whole engine.

We then shut off or disconnect the fuel line while they are running and let them run themselves dry.

We've been doing this for several years now--- we have a convenient source of non-ethanol fuel in our area--- and this and running the engines dry has done absolute wonders for the operation of the motors.

I can reach the motor on our cruising boat dinghy from the dock in our slip, so it's easy to install the hose adapter and hose when we come back from a weekend run or a longer cruise.

A good tip from the Yamaha manual..... On the smaller motors where the earmuffs won't work because they are too large to like flat over the water inlets we use the screw-in hose adapter that installs where the screw in the lower unit is that says "Water" next to it. But---- if you just attach the adapter, connect a hose, and turn it on, most of the water simply comes out the inlet slots in the lower unit and there's not a lot of water for the pump impeller to "bite" on.

Yamaha instructs the operator to wind tape (we use electrical tape) around the lower unit to cover all the water inlet slots. This means that almost all of the water coming through the hose stays in the lower unit allowing the water pump impeller to feed a good strong flow of water to the engine.

When you do this made damn sure you remember to remove the tape when you are through flushing the motor. If you don't, the next time you use the motor the water supply to the pump will be minimal to non-existent and you risk severely damaging the engine.

I don't think running a 2-stroke out of fuel does anything detrimental to the engine at all. As long as it's running it's getting oil and when it stops running it doesn't need any oil. And in our experience, both the four and two strokes stop very quickly once the supply of fuel runs out. The motor on our fishing boat is a Yamaha 90 hp 2-stroke, and when we started running it dry and using non-ethanol fuel its operation improved significantly.
 
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... And in our experience, both the four and two strokes stop very quickly once the supply of fuel runs out.

How do you know that? Or are you just assuming that they stop because they ran out of fuel? If so then your observation isn't very scientific. Maybe they continued to run for a while after the carburetor emptied. How would you know? :) :facepalm: :rofl:
 
How do you know that? Or are you just assuming that they stop because they ran out of fuel? If so then your observation isn't very scientific. Maybe they continued to run for a while after the carburetor emptied. How would you know? :) :facepalm: :rofl:

That's an odd question. Why else would they stop? I don't turn them off, so when they run out of fuel they stop running. Even my dog understands that one.:)

If they have fuel, they run. If they don't have fuel, they don't run. They pull all the fuel out of the carburetor bowl(s), then they pull the fuel out of the manifold(s) between the carburetor(s) and the cylinder(s), and then when there's no more fuel left to run on they--- and I guess this might be a hard concept for some people to grasp--- stop running.

On the 90hp I hit the electric starter after it quits just to make sure there's no fuel left anywhere. It never starts or even fires a cylinder or two, so my guess is that there is no fuel left anywhere in it.

Anyway, the critical thing is to get the fuel out of the carburetor bowl. Because if one has to use ethanol fuel, it starts separating fairly quickly and then starts forming sludgy crap in the carburetor. You can accomplish basically the same thing by removing the drain screw from the carburetor bowl. But it's better to get all the fuel out of everything.
 
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Same as above. Rinse with fresh water and run out of fuel. I kept a 9.9 hp Yamaha 2-stroke running for about 20 years doing this. It still starts on first pull.

The trawler I purchased two years ago had an inflatable with a nearly new 9.9 hp 2-stroke which had apparently been out away with fuel in the carburetor. It would not start and it took a considerable effort to get the gum out of the main jet. It now runs perfectly.
 
I do basically what Marin does and agree w him except about his dogs intellegence. We too get the alcohol free gas locally.
With small outboards sometimes I just put the lower unit in a bucket of water and start them holding on to the engine. It's easier than one would think.
In Alaska for my 60hp Suzuki I filled a big drum of water (plastic) that I'd snake under the engine lowering it w the tilt switch a bit at a time. I cut out an "U" shaped notch in the top edge of the drum. I've done that here too but it takes about 35 gallons of water.
I too have had good experience running OB engines dry but I never do it w a fuel injected engine.
 
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That's an odd question. Why else would they stop? I don't turn them off, so when they run out of fuel they stop running. Even my dog understands that one.:)

If they have fuel, they run. If they don't have fuel, they don't run. They pull all the fuel out of the carburetor bowl(s), then they pull the fuel out of the manifold(s) between the carburetor(s) and the cylinder(s), and then when there's no more fuel left to run on they--- and I guess this might be a hard concept for some people to grasp--- stop running.

On the 90hp I hit the electric starter after it quits just to make sure there's no fuel left anywhere. It never starts or even fires a cylinder or two, so my guess is that there is no fuel left anywhere in it.

Anyway, the critical thing is to get the fuel out of the carburetor bowl. Because if one has to use ethanol fuel, it starts separating fairly quickly and then starts forming sludgy crap in the carburetor. You can accomplish basically the same thing by removing the drain screw from the carburetor bowl. But it's better to get all the fuel out of everything.

Guess I didn't use enough of the correct smileys. That was my attempt at a joke - sarcasm. Guess it was lost in translation :)
 
I just saw an outboard that had been run hard and often by a live aboard sailor for a year and never flushed with fresh water. It's cooling passages were packed with white stuff. I assume it was salt. The engine looked ruined to me. The owner said that the pisser had stopped squirting many hours ago. He assumed that it was just the pisser that was blocked. I'm surprised the engine didn't seize. There was water in the oil so I think it got hot enough to warp the head.

I know it's not possible to flush an engine each time you run it, but ya gotta flush them once in a while. The more often you flush them, the longer they'll last.
 
Anyone know how to best flush a 15 hp 2-stroke Merc with a whale tail? The standard issue flusher for this model doesn't fit with the whale tail in place.

41YUM8kiFNL.jpg


Here's a lousy shot of the water intake. It's on the underside of the anti-cavitation plate.

img_342922_1_1b8ff6806edc2db38ea6e904bcf85fdb.jpg
 
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Regarding potential damage when running a two cycle out of fuel(and oil):

I have a two cylinder outboard that as a separate, float type carburetor for each cylinder. When I run the engine out of fuel, one of the carburetors depletes its fuel (from the float bowl) before before the other. The engine then continues to run (on one cylinder) for a minute or so.

I have always worried about the "dry" cylinder and crankcase half being under lubricated. The reality is that I have been using this procedure on this engine for 25 years (hundreds of flushes) and it still operates as new. Only maintenance so far is been 2 sets of spark plugs and a couple changes of the lower unit oil.

On edit: I have always used regular pump gas that (for the last 10 or 15) years has been blended with alcohol.

Steve
 
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Al,
They are available on Ebay or your local Merc dealer. They say you need to remove prop but you can adapt them so the hose fitting does not go straight down and then it's easy.


PART NUMBER 12612Q2

MERCURY MARINER 6/8/9.9/15HP Engines with water inlet under cavitation plate.
 
Thanks, Blue. Here's what I'm looking at.

attachment.php


With the whale tail in place, this thing doesn't fit. This isn't my engine, but it's configured like this.

8-HP-Long-Shaft-Outboard.jpg
 
I assume the engine does not have a small screw plug for the water chamber below the water pump as a Yamaha does, thus making it impossible to use a screw-in hose adapter?
 
Guess I didn't use enough of the correct smileys. That was my attempt at a joke - sarcasm. Guess it was lost in translation :)

Yes…it did…and Marin's description of care of most outboards is pretty spot on, and for that reason, as it's a bit of a pain, I just luurrrve my Honda 2, because it is air cooled and requires no flushing, and being 4 stroke never fouls the plug, so does not need to be run dry, yet still starts 1st or 2nd pull, even after months unused. And it's very light. Of course it's only ok for a quite small, say 3-4 person, 8-9' tender.
 
I don't do anything to mine. I just hoist the dinghy and engine up on the davits. I rinse the outside of the engine off when I get back to the dock.
I always use Stabil in the gas mixed in with the 2 cycle oil. Never run it dry just disconnect the fuel hose sometimes, but not always.
When I haul the dinghy out for winter storage I flush with fresh water using a 5 gallon bucket then let it run dry.
I never had a fuel issue using the ethanol laced gas we have in CT, never had an outboard overheat due to being plugged with salt deposits.
Knock on teak.
 
Al, they used to make a 'Backflusher' which actually connected to the pee hole and you back flushed the motor with just water pressure. You could not run the motor when doing this so not sure how effective it was. I seem to remember them saying the pressure overcame the spring on the thermostat so did flush top end down. I will Google and see what I can find later today.
 
Marin,
I read it "We run all our outboards, 2-cycle and 4-cycle, on non-ethanol fuel (as we do with our lawnmower, home generator, etc.) That alone make a huge difference in the reliability and longevity of the motor in terms of running properly." The same way and wondered about that. Re lubrication I definitely don't think it's an issue. Not at all.

Peter B,
I'd love one of those little Honda's but I don't think I could stand the racket. Flywright thinks I'm noise sensitive ... probably am. Perhaps I should just buck up and get one. Used to hate that expression "buck up". Lots of other people seem to like them as I see on Craig's List they are not cheap to buy used. I have a water cooled Yamadog 2hp so I'll wear that one out first. I think it's the same weight as the Honda though (27lbs) and I can lay it down anywichway. Not too noisy at half throttle but I can row that fast .... rev it up for that great top end rush (one more hp) and it may be close to the Honda for noise. Can't afford a new engine now anyway.

jleonard,
Your post #19 seems a big plug for Staybil. Glad to hear it. For all our domestic engines (lawn mowers ect) we use the alchol free gas but during the "season" perhaps we don't need it. Think I'll use alchol free gas and Stabil for winter though. Run dry also.
 
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Eric-- Our outboards run okay on ethanol fuel, it's the not-running that's the problem. Ethanol fuel separates pretty quickly and starts to gum up things like carburetor jets, float bowls, and the entire fuel system in general. That's why it's very beneficial to run the motors dry before any period of non-use.

Using non-ethanol fuel probably reduces the need to run motors dry between periods of use other than longer lay-ups. But we still do it with our motors.

We use Stabil in our non-ethanol fuel but not in ethanol fuel. It was some years ago but the outboard tech at Jacobsen Boats and Motors in Ballard (they've since moved to Edmonds) gave me a lengthy discourse on fuels and additives. According to him ethanol fuel actually prevents things like Stabili from working and in fact the use of Stabil results in accelerated separaration. I have no idea if he was correct but once we found an easy source of ethanol-free fuel it wasn't something we were concerned about.
 
We use Stabil in our non-ethanol fuel but not in ethanol fuel. It was some years ago but the outboard tech at Jacobsen Boats and Motors in Ballard (they've since moved to Edmonds) gave me a lengthy discourse on fuels and additives. According to him ethanol fuel actually prevents things like Stabili from working and in fact the use of Stabil results in accelerated separaration. I have no idea if he was correct but once we found an easy source of ethanol-free fuel it wasn't something we were concerned about.

Marin that's funny (ironically) because my nephew who worked for a local John Deere dealer at the time went to a class and they said Stabil was a good additive for ethanol...but of course the JD additive was better.
I just know it has appeared to work for me.
 
I'll chime in here. We bought our Whaler 1-year ago new. The dealer (MarineMax) advised us to add Stabil to every fill up especially to ethanol containing fuels. The Merc owners' manual states that the motor(s) is designed to accept ethanol fuels safely. The motor is a 25 hp Merc 4 stroke. I've been doing that as directed. Have not been flushing with fresh water but I will in the future as it certainly can't hurt. I have never run the motor dry.
 
I always flush my E-Tec's from the screw in hose adapter for about 10 minutes and done. That's for a 40HP and 115HP though. Never run them out of fuel. Seems to work just fine and they always start up. But I never run them w/ethanol gasoline, Only rec 90.
 
Never done anything, just run it. If its gonna set awhile I run some Stabil thru it. I really dont like running a two stroke out of gas (oil?) but a lot of folks do it. I have flushed a few with Muratic or similar, especially if overheating was a problem. Changed lots of thermostats.

Pretty much our program to for our 2 stroke Mercury 40hp. It's been very heavily used, all salt water. Never flushed it once myself in going on 8 years now. I do have it serviced about once a year or so. I am embarrassed to say how abused this motor has been but the damn thing keeps running like a top. May be that running it is the secret.
 
Stabil like most additives has been modified since the advent of ethanol gas.

Some brands have different products for different fuels..gotta read the label.
 
I take my 2 hp dinghy outboard off and rinse and dry it after every use. I never flush it since it doesn't have a cooling system. I store it in the lazarette between uses. I have never had a problem with fuel and I don't use any additives. It starts immediately even after a winter sitting in storage. I have had it for 5 years and have never had it serviced. Never a problem.

It is a Torqeedo ;)
 
The outboard maintenance guys I have talked to stressed what Marin said: run the outboard out of fuel when not in use. I use Mercury Quickare #1 as fuel treatment, 'cause that's what the Mercury guys said to use. Evidently this stuff has sufficient stabilization for a year, but I won't keep my fuel for the new year. Fuel without ethanol is mostly unavailable in BC.

I have a 10 gal container that has a hose attachment, and I run water through my me fine when I can when cruising. I figure I can use it 4 times before it runs out. If it's raining I can fill it with water running off the boat deck. Best I can do.


Jim
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