Accidentally ran twin engine on one cylinder!!
- Thread starter meds613
- Start date
Check the plug in the cylinder that wasn't firing, if it's good leave it, change the oil and you're done. Don't overthink it.
^^^ this.
theres no load on the cylinder. the cylinder will be hot, fuel won’t want to condense on it. These are lower compression engines. Any that gets in the oil will evap off - air cooled engines run hotter than liquid cooled.
plug back in and go. No need to swap the spark plug.
theres no load on the cylinder. the cylinder will be hot, fuel won’t want to condense on it. These are lower compression engines. Any that gets in the oil will evap off - air cooled engines run hotter than liquid cooled.
plug back in and go. No need to swap the spark plug.
gathermewool
Site Donor 2023
I might be missing something, but I don’t see the logic in assuming the crankcase is diluted with fuel or that there was excessive cylinder wash down. The spark plug was missing. Wouldn’t the fuel mostly be ejected through the plug hole each compression stroke - you know, path of least resistance. Wouldn’t that same cylinder have trouble drawing a good vacuum, as well?
Barring any logical rebuttal I’d simply mow on as if nothing happened. If you caused any wear it might be to the bottom of the bearings, due to a possible slight over-extension of the piston at zero load. Considering these engines are low-compression, I wouldn’t lose any sleep over it.
Barring any logical rebuttal I’d simply mow on as if nothing happened. If you caused any wear it might be to the bottom of the bearings, due to a possible slight over-extension of the piston at zero load. Considering these engines are low-compression, I wouldn’t lose any sleep over it.
I wouldn't even worry about it. Big multi cylinder radial engines ran all the time with the bottom cylinders misfiring when they first started up. And continued until they pumped all of the oil out of the lower cylinders that leaked down into them.
Sometimes it could take running them over a minute or more to push out the old oil, while the engine was washing it out with new fuel. They knew by sound, and when the engine stopped smoking, they were banging on all of them. They were some of the most powerful and rugged aircraft engines ever built. Your engine will be fine.
Sometimes it could take running them over a minute or more to push out the old oil, while the engine was washing it out with new fuel. They knew by sound, and when the engine stopped smoking, they were banging on all of them. They were some of the most powerful and rugged aircraft engines ever built. Your engine will be fine.
My sister in law ran her Kawasaki powered V-Twin (21HP?) mower for an entire season on one cylinder, due to critters eating a spark plug wire over the winter. She was having trouble going up the hills while mowing, and would mow downhill instead. Hahahah. OMG. She mows about 2 of the 10 acres they own in VT.
Unrelated note: My leftist brother utterly hates the mower because it uses gas!
He is somehow convinced that mowers should be electric and would yell at his wife for mowing. She just left him last week, I wonder if he will ever mow?
I heard her mowing when I visited last year and immediately knew something was wrong. I pulled the cover off and was able to fashion a temporary repair until she replaced the coil. We did not change the oil or anything else. After the repair, the engine ran perfectly, no smoke, and as far as I know, continues to operate normally.
Unrelated note: My leftist brother utterly hates the mower because it uses gas!
He is somehow convinced that mowers should be electric and would yell at his wife for mowing. She just left him last week, I wonder if he will ever mow?I heard her mowing when I visited last year and immediately knew something was wrong. I pulled the cover off and was able to fashion a temporary repair until she replaced the coil. We did not change the oil or anything else. After the repair, the engine ran perfectly, no smoke, and as far as I know, continues to operate normally.
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Understand there was still oil splashing on the piston and rings so there is really very little danager. However fuel that wasnt burned did get squeeezed thru the rings. You will want to change the oil. Other than that, it will be fine.
It wasn't explicitly stated, but I think he left the plug wire off, not the plug out of the head.
gathermewool
Site Donor 2023
Ah, reading comprehension. My one weakness.
My 22hp B&S was running really badly for about a month of mowing, probably 5-6 hours. I did a bunch of stuff including cleaning the carb twice before eventually discovering one of the pushrods had popped loose. It was running poorly because the intake valve of one cylinder hadn’t been opening.
That was at least 3-4 years ago and it’s still running fine.
That was at least 3-4 years ago and it’s still running fine.
Been there, done that too🤣Ah, reading comprehension. My one weakness.
