Power up and down

stanley

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I have an MTD Yard Man push mower I bought new in May, and while it's going you can hear the power go up and down. I don't know how else to explain it. What do you think the problem could be?
 

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KennyV

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Carb adjustment most likely will get it.. :smile:KennyV
 

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Mac 624

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Bougth in May??? Any warranty on it? If Yes...take it back to the dealer. He should be able to solve the prob.

If not...there is a screw and if You turn it in, the governeror will not move that much.

I know that I am a bad explainer, but english i not my common language...and show it by computer will mean, that I would get no sleep.
 

Michael

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Use premium fuel, what is on this for a motor???
Michael
 

jhwentworth

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I have an MTD Yard Man push mower I bought new in May, and while it's going you can hear the power go up and down. I don't know how else to explain it. What do you think the problem could be?


If your mower engine is "hunting" (engine RPM going up and down) the most likely problem is bad fuel or an obstruction in the low or high speed jet.

The suggestion about warranty repair might work, but the dealer probably won't cover a bad fuel or "crap in the carb" repair under warranty. The problem is that neither you or the dealer will know if it's covered by warranty until the work is mostly done.

Questions: Did you refuel your mower just prior to the problem occurring? Do you store your fuel in a clean, sealed, container away from moisture? Are you using old fuel? Are you the only person who uses the mower?

Mowers that sit over the winter with fuel in the carb and tank can build up junk that will obstruct the small opening in the jets, but during normal summer operation this is unusual if the mower is run regularly. Most of the junk that gets into the carb in the summer gets there through the fuel supply.
 

KennyV

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If your mower engine is "hunting" (engine RPM going up and down) the most likely problem is bad fuel or an obstruction in the low or high speed jet.

The suggestion about warranty repair might work, but the dealer probably won't cover a bad fuel or "crap in the carb" repair under warranty. The problem is that neither you or the dealer will know if it's covered by warranty until the work is mostly done.

Questions: Did you refuel your mower just prior to the problem occurring? Do you store your fuel in a clean, sealed, container away from moisture? Are you using old fuel? Are you the only person who uses the mower?

Mowers that sit over the winter with fuel in the carb and tank can build up junk that will obstruct the small opening in the jets, but during normal summer operation this is unusual if the mower is run regularly. Most of the junk that gets into the carb in the summer gets there through the fuel supply.

I believe you have covered this problem exactly ... and this accounts for most all the small engine problems.... :smile:KennyV
 

cren

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A friend in WA had a similar issue but it seemed to be with an older clunker type. What brand do you have and how long have you had it for?
 

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busted bolts

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Most new engines now run a fixed jet carb, meaning that it is factory adjusted. When all conditions are met, clean air filter, proper fuel, clean and water free fuel, clean carb, will it run to their specs. The probem mostly cpmes from water in the fuel. Since the fuel now is blended with 10% ethenol alcohol, this is attracted like a magnet when condensation is present. This happens most from temp changes warm days/cool nights, and humidity. Water is heavier than gas, so it will form on bottom of fuel tank, carb bowl. or bottom of fuel can. It never goes away untill removed. If you were at the last of the fuel in your can, it is possible that water has passed into the mower fuel tank and if gravity fed to carb it went to the fuel bowl. Check all of these sources and let us know. Good luck:thumbsup:
 

carl22

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My brand new Weed Eater brand walk behind does that until it warms up. Once it's warm (5 to 10 minutes), it runs like a charm. I'm thinking that it may be designed to run that way, as most carburated engines run a little rough until they're warmed up.
 

indypower

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Dirty carb will cause this problem as well as a clogged air filter.
 
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