Johnson 15 hp Cuts Out

gogittum

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LDUBS said:
Fuel stabilizer? I religiously use Honda's Fuel Stabilizer (because I have a Honda outboard). It is supposed to address issues with ethanol laced gaso.

In my previous boat I had a 3 gallon portable tank. I didn't like the capacity. But one advantage of a small tank is with normal usage the fuel can be turned over fairly quickly.

Something I know little about and don't have is a fuel/water separator filter. Seems like a good idea, but as I say, I'm not one to ask.

I tried that with a different motor last year and not sure what I did wrong.....or what went wrong. I used the Yamaha version of stabilizer. Put 6 gal of fresh gas in the tank, then measured out the recommended dosage of stabilizer and of 2 stroke oil and added them. Motor wouldn't run. Pulled some gas to check it and it was almost black. Never seen anything like it.

When I put a different tank on it and got the system cleared, it fired right up and was fine. I ran that "stabilized" fuel thru my car, one gallon at a time when I filled up, to get rid of it. I'm hesitant to try again.
 

LDUBS

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gogittum said:
LDUBS said:
Fuel stabilizer? I religiously use Honda's Fuel Stabilizer (because I have a Honda outboard). It is supposed to address issues with ethanol laced gaso.

In my previous boat I had a 3 gallon portable tank. I didn't like the capacity. But one advantage of a small tank is with normal usage the fuel can be turned over fairly quickly.

Something I know little about and don't have is a fuel/water separator filter. Seems like a good idea, but as I say, I'm not one to ask.

I tried that with a different motor last year and not sure what I did wrong.....or what went wrong. I used the Yamaha version of stabilizer. Put 6 gal of fresh gas in the tank, then measured out the recommended dosage of stabilizer and of 2 stroke oil and added them. Motor wouldn't run. Pulled some gas to check it and it was almost black. Never seen anything like it.

When I put a different tank on it and got the system cleared, it fired right up and was fine. I ran that "stabilized" fuel thru my car, one gallon at a time when I filled up, to get rid of it. I'm hesitant to try again.


Turned black and motor wouldn't start at all with the stabilizer -- holy cow, I wonder what is going on. For mine, I use the recommended 1 oz to 10 gallons of fuel routinely. I run it 100% of the time in both my four stroke Honda outboard and two stroke Stihl leaf blower. Sure never noticed it turning black. Note my fuel doesn't sit for months at a time and I use the motor year round. That would make a difference I think.

I sure wish I could help. Fingers crossed you discover the issue.
 

gogittum

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I guess the only thing to do is keep doing the same thing until it's all out of there, but I'm actually starting to worry about the plug threads in that aluminum head. How many times can you remove those plugs ?? It's not hard, but it Is tedious.

Neighbors must've thought I'd lost it yesterday. I can't see the spark tester in daylight, so got a big box out of storage and hung it over my head and motor while I spun it with the drill motor. It's got spark.

I don't like using ether because it washes oil off the cylinder walls, but then, by the same token, if it's sucking water into the cylinders, that's going to do the same thing. Don't see any easy way around it. Where's the water coming from ?? How much can be in the crankcase ?? Aaarrgh ! ! !
 

cyclops2

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Your gas place is SCREWING YOU !!

If you ARE covering the gas tank when not running it. Or rain is coming into the tank.
 

Pappy

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You're not quite done with it.
With an overheat as severe as yours you have probably melted the water tube grommets beneath the powerhead. You never mentioned checking compression either but well worth checking after a bad overheat.
The grommets are a different story. the supply tube grommets normally melt inward and block a good percentage of water flow. You will see water coming out of your overboard indicator but keep in mind that is simply an indicator. It tells you nothing about how well the powerhead is being cooled. Chances are you will not have sufficiient water volume to properly cool the powerhead at WOT.
There are a couple of threads on this in the ENGINE forum (which is where this thread should be located). Well worth reading.
The normal reply to this information is " I checked the indicator and it is still working at WOT so it must be good" Not so but up to you whether you want to check and be sure. Run additional oil in your fuel until verified......just another tip.
 
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