Mower running poorly - Ethanol gas?

C

cbrf3

Joined
Oct 6, 2020
Messages
152
Location
Atlanta, GA
One of our mowers is a standard Troy-Built walk behind 6.5 B&S. I have had it about 10 years, got it used from a neighbor.
The plug looks good, tried others, air filter is clean and the gas is fresh. Over the past few years it has just been running worse overall like it is almost sputtering out of fuel, not able to keep a nice even RPM. It seems I hear a lot of mowers in the area running the same way. In the past this means my air filter needed a quick cleaning and it was back to normal, not any more.

So I drained the gas tank, ran it dry and refilled with Non-Ethanol gas. This made zero difference. I have a few more mowers in the garage but they do not seem to want to run very well either, all have had the simple things checked.

Has the ethanol gas already done damage to the carb components or is it likely something else? Pull the head off and have a look?
 
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cbrf3 said:
One of our mowers is a standard Troy-Built walk behind 6.5 B&S. I have had it about 10 years, got it used from a neighbor.
The plug looks good, tried others, air filter is clean and the gas is fresh. Over the past few years it has just been running worse overall like it is almost sputtering out of fuel, not able to keep a nice even RPM. It seems I hear a lot of mowers in the area running the same way. In the past this means my air filter needed a quick cleaning and it was back to normal, not any more.

So I drained the gas tank, ran it dry and refilled with Non-Ethanol gas. This made zero difference. I have a few more mowers in the garage but they do not seem to want to run very well either, all have had the simple things checked.

Has the ethanol gas already done damage to the carb components or is it likely something else? Pull the head off and have a look?
Click to expand...
My experience with carbonated engines.... it takes very little time for ethanol to damage them.... especially aluminum.... Ones I was able to dismantle were full of a gunk that choked them up, and the metal was disintegrating ... New carbs are not very expensive.... that would be my course of action if the rest of the mower still has some life in it....
 
It’s probably a bit of gunk in the carburetor that slowly builds every time the machine sits for a couple weeks from the ethanol. A whole new carb is so cheap on amazon these days I often don’t even bother trying to clean the original. Just pay 15 bucks for a new one and swap them out.
 
SailingWJ said:
My experience with carbonated engines.... it takes very little time for ethanol to damage them.... especially aluminum.... Ones I was able to dismantle were full of a gunk that choked them up, and the metal was disintegrating ... New carbs are not very expensive.... that would be my course of action if the rest of the mower still has some life in it....
Click to expand...
Yet, I have been operating dozens of outdoor power equipment on E10 gas for over 18 years and don't have problems that I can associate with the ethanol. Do some states have poorer quality fuel than others? I DO believe that people living in the south need to manage their fuel storage and be much more careful due to the heat effects on fuel. I also believe it is just as reasonable to blame degraded Chinese manufacturing for today's outdoor equipment problems. I do like spasm3's hypothesis.

Buy one of those $18 Chinese carbs on Amazon or Ebay, pop it on, and see if that was the problem. A carb kit will be a bit cheaper, if you can find one.
 
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doitmyself said:
Yet, I have been operating dozens of outdoor power equipment on E10 gas for over 18 years and don't have problems that I can associate with the ethanol. Do some states have poorer quality fuel than others? I DO believe that people living in the south need to manage their fuel storage and use much more careful due to the heat effects on fuel. I also believe it is just as reasonable to blame degraded Chinese manufacturing for today's outdoor equipment problems. I do like spasm3's hypothesis.

Buy one of those $18 Chinese carbs on Amazon or Ebay, pop it on, and see if that was the problem. A carb kit will be a bit cheaper, if you can find one.
Click to expand...
You’ve never pulled apart a carb and found a mess of green/tan looking crud? I see it constantly flipping mowers. Since mowers sit all winter up here there’s always a ton of them that won’t start in spring cause the gas in the carb has turned to sludge.
 
I have never used non ethanol gas in anything I owned . Cars , trucks , or OPE . One time I had to drop the float bowl on an edger motor and clean some white powdery crud out of the float needle . It had set up for months . I think a lot of things get blamed on ethanol that are probably caused by other issues . I realize that I am in the minority here but that's just been my experience .
 
Warlord said:
You’ve never pulled apart a carb and found a mess of green/tan looking crud? I see it constantly flipping mowers. Since mowers sit all winter up here there’s always a ton of them that won’t start in spring cause the gas in the carb has turned to sludge.
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No, I haven't. I once had a carb problem on a mower that sat for 2 years, to be expected. I use Stabil in my OP in November and they start fine in April, stored in unheated areas over winter. My chainsaws, trimmers, etc. often sit 6 months between uses, maybe the Stihl 2 cycle oil with stabilizer helps? I did develop a carb problem in my workplace 13 year old Exmark Zturn. People said it was probably clogged main jets. I ran about 5 tanks of fuel with cleaner in it and now it runs like new again. Was it the Ethanol or just some crud that made it's way into the carb somehow.

I have no hard evidence that ethanol is the culprit of bad engine operation. I do run into people locally that believe ethanol fuel is the devil and I wonder why there is such disparity in results. Warlord, your experience flipping mowers makes me think that maybe those mowers had very poor care that you are not aware of?
 
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doitmyself said:
No, I haven't. I once had a carb problem on a mower that sat for 2 years, to be expected. I use Stabil in my OP in November and they start fine in April, stored in unheated areas over winter. My chainsaws, trimmers, etc. often sit 6 months between uses, maybe the Stihl 2 cycle oil with stabilizer helps? I did develop a carb problem in my workplace 13 year old Exmark Zturn. People said it was probably clogged main jets. I ran about 5 tanks of fuel with cleaner in it and now it runs like new again. Was it the Ethanol or just some crud that made it's way into the carb somehow.

I have no hard evidence that ethanol is the culprit of bad engine operation.
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I sometimes wonder if it’s the differing amounts of ethanol and possible quality that causes different experiences for people. With preventative treatments like stabil I‘m not surprised you have few issues. The mower that sat for 2 years though wouldn’t have likely had a problem if there was zero ethanol in the fuel since it wouldn’t have attracted water for 2 years sitting there. I have chainsaws that sit for 2-3 years on trufuel and fire right up as if they were just used the week before. If I left ethanol gas in there for 3 years they would be in need of carb overhauls or more likely total replacement of the carbs. I’ll try to find some pictures of the carbs I pull apart that are clogged right up. They look like they’ve been sitting at the bottom of the ocean for 50 years inside lol.
 
@Warlord - My 2 year lawn mower problem was many years ago on non ethanol gas.

"If I left ethanol gas in there for 3 years they would be in need of carb overhauls or more likely total replacement of the carbs." Please, no offense intended, but I have to sigh "duh"! Anyone that hasn't learned that ethanol fuel needs to be managed much more careful than non ethanol fuel deserves to have equipment problems. Your descriptions are owner problems that exacerbated ethanol problems. Adapt and move on.

Warlord and Warstud! I'll side with the Michigander.
 
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The E10 is fine as long as you burn it up in a month or so. Storage over the winter is where you run into problems. It collects moisture until it finally can't hold anymore and it separates. Small carbs get gunked up with an algae looking crap. Even if it starts fine in the spring it will still build up over a couple years and become a problem.
 
tmorris1 said:
The E10 is fine as long as you burn it up in a month or so. Storage over the winter is where you run into problems. It collects moisture until it finally can't hold anymore and it separates. Small carbs get gunked up with an algae looking crap. Even if it starts fine in the spring it will still build up over a couple years and become a problem.
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Exactly and that crud breaks loose and plugs up the tiny passages in a small carb.
 
doitmyself said:
@Warlord - My 2 year lawn mower problem was many years ago on non ethanol gas.

"If I left ethanol gas in there for 3 years they would be in need of carb overhauls or more likely total replacement of the carbs." Please, no offense intended, but I have to sigh "duh"! Anyone that hasn't learned that ethanol fuel needs to be managed much more careful than non ethanol fuel deserves to have equipment problems. Your descriptions are owner problems that exacerbated ethanol problems. Adapt and move on.

Warlord and Warstud! I'll side with the Michigander.
Click to expand...
Surprising that the gas turned that long ago. Was there build up inside the carb or did you just have to drain and refill with fresh gas? If ethanol fuel needs to be managed “much more carefully than non ethanol fuel” perhaps it is as bad as people say it is? The general public isn’t educated about such things and they’re the ones that have the issues. Fine with me though cause I can buy practically new mowers every spring and flip them for decent profit after a quick carb clean. 😂
 
I know about healthy eating and I still am 20 lbs. overweight and eat unhealthy things like the bratwurst (bad) that I charred (bad) on the grill yesterday.

Guilty as charged. Seems to be the similar point you are trying to make about ethanol fuel. Bad, yes. O.k. if managed, yes, maybe? :)
 
I have a BS motor that over time the gas tank gets water in from sitting with E10 in it. And there is no way to completely empty the tank. You have to use rags to suck up whatever is left in there. Even taking the carb off and then the tank you still cannot completely drain it. It's a terrible design. I put a drain plug in it but it leaks so problem solved as far as long term storage......

But it runs good until the water level builds up.
 
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