My lawn mower has a new battery. I just filled it up with gas. It will slow down and act like it’s going to cut off. Then it will speed up and the motor sounds normal again. It does this about every two or three minutes.
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October 19th, 2009 at 11:20 pm
Sounds like a carburetor problem to me.
October 19th, 2009 at 11:20 pm
dirty air filter.
October 19th, 2009 at 11:36 pm
I agree, with the adage, gas spark or air. One other thing, on a riding mower, there is typically a safety switch on the seat. If you get up out of the seat while it is running, the mower will shut off. Could be a bad safety switch on the seat or that switch is out of alignment causing the mower to cut on and off.
October 19th, 2009 at 11:39 pm
Sounds like it might not be getting enough air. Clean the air filter. You might also adjust the carb to a bit less lean. Good luck.
October 20th, 2009 at 12:18 am
Sounds like you don’t have the choke pulled out and the gas is not getting to the engine the way it should. When all else fails, try reading the manual that came with the lawn mower, unless you got it from a friend or garage sale.
October 20th, 2009 at 1:06 am
Any smoke when it does this? a lean running engine can run good for few….. then dround out (of course no black smoke, its running lean) And a rich engine can run good then all of a sudden get a load of gas puff black smoke.
Sorta sounds like the engine isn’t getting gas to the carb, in a steady supply…… in other words the gas gets there very slow….. take the fuel line off at the carb, let it go real quick and watch for a fast and steady flow to see if this is the case…. usually it can be a non venting gas cap, or clogged fuel filter (some tanks have a mesh screen at the outlet as well)
October 20th, 2009 at 1:18 am
Remember the old adage, gas spark or air. The first thing that I would eliminate is the gas. Start with a tank of fresh gas. Secondly I would squirt some carburetor cleaner into the carb. while you have the air cleaner off, inspect it and clean or replace as needed. You also may want to inspect the condition of the plug. A fouled plug can cause rough running or missing although I personally lean to the air or gas theory.
October 20th, 2009 at 1:32 am
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October 20th, 2009 at 2:26 am
when you start it you have to have full choke on to start. after it starts, are you putting the choke off again. because if you dont it may run rough and it will smoke to.and my be pull the spark plugs out and clean them and a new air filter. and before you shut your mower down bring it to idle. then shut it off. because if you dont it will backfire when you restart it
October 20th, 2009 at 3:04 am
There could be an air bubble in the gas line.
October 20th, 2009 at 3:16 am
Sounds like the cylinoid it the carburator is going out. It’s an easy fix for any halfassed mechanic. It’s not a part you realy need to run it but it has to be there to hold the bowl on the carb. If you take it off, on the top is a spring loaded plug that stays up if it stops working. The spring is external so you can just take it off and put the cylinoid back on. Don’t put the plug back on the cylinoid if you do this.