Repairs Bad Gas

[reynoldston]

Well this year so far I have a mower and a chainsaw that wouldn't start. Both Jobs they were getting everything they needed to run. As soon as I put fresh gas in the fuel tank they both started and ran good. The old gas smelled OK yet but it lost its kick for the equipment to run.

 

[reynoldston]

I have seen it on this forum that the ethanol in the gas loses it ability to run a engine after it sits. I never took it too serious because its something I didn't run across in my repairs till this spring. I have just ran across my fourth repair job this spring that I had to drain the old gas out for fresh gas before they would run. What gives, are they adding more ethanol to the gas now? The customers are asking me what they should do about it but I really don't have a good answer for them other then run the mower out of gas each fall which to me is a poor answer. I also don't understand why some mowers are having this problem and others don't? Could it be that its the amount of ethanol in the gas which would be different by brand? Do they even sell gas without ethanol anymore and if so I never see it?

 

[Fish]

I think that the fuel companies vary their mixtures so often that they probably couldn't give you a decent recipe list for any
particular tanker, as the change the formula as the seasons change anyway, and the sticker says may contain up to whatever
percentage of ethanol. I have had folks bring back a trimmer in the spring, that I worked on last fall, complaining that
the trimmer won't start, etc.. While they are still there, I'll dump their tank in jar, and pour a dribble on some paper in the burnpile, then step back and fling a match at it, it usually takes several tries, and then takes off like old kerosene...

 

[reynoldston]

I think that the fuel companies vary their mixtures so often that they probably couldn't give you a decent recipe list for any
particular tanker, as the change the formula as the seasons change anyway, and the sticker says may contain up to whatever
percentage of ethanol. I have had folks bring back a trimmer in the spring, that I worked on last fall, complaining that
the trimmer won't start, etc.. While they are still there, I'll dump their tank in jar, and pour a dribble on some paper in the burnpile, then step back and fling a match at it, it usually takes several tries, and then takes off like old kerosene...

Never tried the match trick, but that would be a good reason it wouldn't run a engine. I will take a guess and think that they bought there fuel late in the season so maybe its a winter blend that go's bad?

 

[Fish]

No, I have seen some mixes go bad after a month or two, no matter what time of year. I just encourage my folks to mix 1 gallon at a time, and get rid of the mix going into winter unless they run chainsaws for firewood, and run the tank dry if possible.

 

[pugaltitude]

Just tell your customers to use a fuel additive.
All engine manufacturers are promoting their own.

 

[Fish]

Doesn't work.

 

[pugaltitude]

I disagree with that.

I have done all my own tests with different fuel being left in different conditions and using a briggs fuel additive 992380, fuel seems to stay fresher and not cause bad starting or rough running.

 

[Fish]

Well you may be right, as I just rely on what my customers tell me they use as their fuel mix, and since I pretty much work on Stihl, well.

Customers usually lie to me, especially when they want me to fix something for free. So are you saying that the Briggs additive works, and no others? Or the Stihl additives, do you have any input?

 

[pugaltitude]

I only use briggs additive and nothing else but problems over here with fuel duty being put on additive and so it may not be available soon.

I have put fuel in different containers and different environments.
Now if in damp conditions with then more signs of water which seems to be due to ethanol/alcohol attracting moisture.
Now a sealed container and dry environment and fuel has no sign of water.
Test done over couple of months.

But

I have had fuel sitting in my own mower for 6 months and causes no problems.
Seems to be conditions fuel is kept thats causing problems.