Dies After 45 Minutes Running

[Fnu Lnu]

Dave,
THAT, is Very Valuable Information.

I am on a project that I need to finish before getting back on the Briggs & Stratton engine. As soon as I can I will test the Spark Color.

Thank You So Much!

 

[Rivets]

Color of the spark makes very little difference, you just need to check to see if you have any spark at all when the unit dies.

 

[Tiger Small Engine]

Color of the spark makes very little difference, you just need to check to see if you have any spark at all when the unit dies.

So does blaming lots of issues on 87 octane 10% ethanol fuel. All my small engines run great on it. The debate continues…

 

[Fnu Lnu]

So does blaming lots of issues on 87 octane 10% ethanol fuel. All my small engines run great on it. The debate continues…

My apologies if I offended you about my preference of fuel type. It is simply that my personal experience with 87 Octane 10% Ethanol Fuel has been that when it is left in the tank too long the fuel sours and starts to smell bad. Also, left in the carburetor too long it gums up. I have had to replace the carburetor on 3 different machines that had been left un-running for about a year with 87 Octane 10% Ethanol Fuel in the carburetor.

Some people have explained to me that the 87 Octane 10% Ethanol Fuel left untreated will only last about 6 months. Treated with a fuel stabilizer extends it possibly another 6 months.

Because I have 9 or more small engine machines I store extra gasoline, upwards of 20 gallons or so. Also I have some machines that will not be used for a year or more. One season I was burning 2-year-old untreated gasoline as late as June because the year before was so hot and dry that I did not mow the yard at all.

We live in a small population county in the south central Texas hill country. When I went to the local supplier to refill my cans I asked the owner how long this gasoline will last. The owner, in turn, called to an older man by name who was there and asked him. The old man said that he did not know how long, but he knew it would last at least 7 years. Then someone told of starting a motorcycle on the third kick that had been setting in a barn for 10 to 15 years. The old man who owned it could not remember when it was last used.

I very seriously doubt that 87 Octane 10% Ethanol Fuel would last much more than 9 months left untreated without having some sort of Start / Run issues.

If I offended you with my comment about fuel preference, then I would ask you to accept my apology, that was not my intention.

 

[Tiger Small Engine]

My apologies if I offended you about my preference of fuel type. It is simply that my personal experience with 87 Octane 10% Ethanol Fuel has been that when it is left in the tank too long the fuel sours and starts to smell bad. Also, left in the carburetor too long it gums up. I have had to replace the carburetor on 3 different machines that had been left un-running for about a year with 87 Octane 10% Ethanol Fuel in the carburetor.

Some people have explained to me that the 87 Octane 10% Ethanol Fuel left untreated will only last about 6 months. Treated with a fuel stabilizer extends it possibly another 6 months.

Because I have 9 or more small engine machines I store extra gasoline, upwards of 20 gallons or so. Also I have some machines that will not be used for a year or more. One season I was burning 2-year-old untreated gasoline as late as June because the year before was so hot and dry that I did not mow the yard at all.

We live in a small population county in the south central Texas hill country. When I went to the local supplier to refill my cans I asked the owner how long this gasoline will last. The owner, in turn, called to an older man by name who was there and asked him. The old man said that he did not know how long, but he knew it would last at least 7 years. Then someone told of starting a motorcycle on the third kick that had been setting in a barn for 10 to 15 years. The old man who owned it could not remember when it was last used.

I very seriously doubt that 87 Octane 10% Ethanol Fuel would last much more than 9 months left untreated without having some sort of Start / Run issues.

If I offended you with my comment about fuel preference, then I would ask you to accept my apology, that was not my intention.

No need to apologize whatsoever. Today’s fuels (87 ethanol, 89, 91, 93) are not what they used to be say 20 years ago. Fuel treated with stabilizer (91 no ethanol) will often not last the two years that is claimed to start and run a small engine. I am not a fuel stabilizer fan.I see lots of fuel from customer equipment with water in it. They claim they are running non ethanol fuel. Keep it moving (fresh fuel) is my mindset. If you are not going to use the equipment for extended periods of time, dump or drain it out.

 

[ILENGINE]

No need to apologize whatsoever. Today’s fuels (87 ethanol, 89, 91, 93) are not what they used to be say 20 years ago. Fuel treated with stabilizer (91 no ethanol) will often not last the two years that is claimed to start and run a small engine. I am not a fuel stabilizer. I see lots of fuel from customer equipment with water in it. They claim they are running non ethanol fuel. Keep it moving (fresh fuel) is my mindset. If you are not going to use the equipment for extended periods of time, dump or drain it out.

If the fuel has water in it, at that point it is ethanol free. Because the water has captured the ethanol and removed it from the equation. So their 87 with ethanol is now 85 octane.

 

[bluesky]

I had the same problem as the OP. After cleaning the carburetor several times with no improvement. we found the problem. The fuel filter "in the fuel tank" on the end of the fuel line was pluged. Replacing that filter has solved all the starting/running issues.
We used a stiff wire with the end bent into a hook ( J shape) to grab the fuel line and pull it out through the tank fill hole.






9J

 

[JohnFrancis]

Unless you took it apart, the vent could still be plugged. Next time it does it, remove the fuel cap, and see if that fixes it.

I’ve also found debris stuck in the fuel lines after replacing the fuel filter and removing the cap to check. Once it was dead wasps… Blew out the fuel lines and has been running great for several years.

 

[Gord Baker]

SkippyDiesel,
I really should have said that the fuel tank is plastic. I misspoke. Also, as to your comment; "Water may be worse with ethanol blends"; thus the reason that I only use real gasoline.

At the local small town source for "real gasoline"; one day last year (2023) I was buying more fuel because I had finally used up the absolute last of the fuel that I bought back in 2021. I asked the owner how long this gasoline will last, explaining that what I was currently burning (remember that this was last year) was two years old. He asked another customer, an older gentleman; "You know better than I do, how long does this gasoline last?". The old man answered; "At least seven (7) years.".

That is why anyone I am visiting with and the conversation gets around to small engines, I highly recommend that they avoid using automobile gas and then tell them of a few places where they can get the real gasoline.

Thank You for reminding me about metal fuel tanks. Of the 7 or so small engine units that I have, 2 of them have metal fuel tanks. I will be more careful about Winterizing them this year because of your advice.

Use a funnel with a fine screen when refueling. Ethanol fuel lasts for about 30 days before degrading. Don't drain out the last dregs from a tank metal or plastic. That is where the Water is.

 

[Thornback]

I had the exact same heat problem with my lawn mower. It was a flat head engine, not an OHV. It would run about 20 minutes and then shut off. It would not restart until it cooled off. I was told the valve seats were soft and over the years the valves would hammer the seats letting the valves rest further into the seat thus reducing the valve stem gap. Once the engine heated up the expansion would close the valve gap and then the engine would lose compression because the valves did not seat. I ground about .010 off the end of each valve stem and that cured the problem. When your mower stops you might test the compression to see if that is your problem.