Troy-Bilt Pony Riding Mower engine popping while idling and running


Old 05-16-17, 08:30 AM
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Question Troy-Bilt Pony Riding Mower engine popping while idling and running

My mower was popping loud occasionally while idling. But when running it was ok. So, I gave it an oil change, new spark plug and air filter. Now it's worst!!! It's not only popping during the idle, but it's also popping while running, and it's more frequent. Help!!!

Troy-Bilt Pony Riding Mower
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Old 05-16-17, 09:46 AM
Join Date: Jan 2010
Location: North East Kingdom of Vermont
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Without knowing the engine, I'd venture that you'= have a ninor air vent thatis clogged in the carburetor . . . . probably due to fuel additives being deposited (which is common when using 10% ethanol fuel.

My snowblower has/had this problem and besides for the popping, it would surge at idle; but would smooth out and run find when under load.

Someone else may have a quicker solution, but consider cleaning the carburetor and examining EVERY little port, vent, or orifice, and make sure it's clean.

Some may suggest using a spray cleaner; but that's usually just superficial, and doesn't get into the areas that are causing the problem . . . . and the problem may be an obstruction not much bigger than a grain of salt !

Some may recommend soaking and plowing out the passages; but I don't know the intricacies of your carburetor.

If there was a quickee solution, I'd reveal it.
Old 05-16-17, 02:22 PM
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The engine is Briggs & Stratton, 17.5HP. Although I bough the mower couple of years ago from Lowe's, the engine has Model/Year: 2011.

I'll look for the carburetor cleaning instruction on Youtube.

I'm also wondering, I've been adding STA-BIL 2-Cycle or 4-Cycle Engines Fuel Additive Storage, and the problem started afterwards. Could be coincidence since my other push mower and trimmer doesn't have problem, yet.
Old 05-16-17, 02:58 PM
Join Date: Jun 2006
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I would suggest giving it a strong dose of SeaFoam whcih will clean the minor buildup of varnish and probably solve your problem. Have a good one. Geo
Old 09-16-18, 10:04 AM
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Sorry for long delay and restarting this thread. Finally got little more time to learn about this riding mower.

I've already had oil changed, replaced spark plug and fuel filter, and tried SeaFoam, but it didn't help.

Now, it starts up for few seconds, then it dies. I'm gonna try to remove the carburetor for cleaning. Is there any recommendation or things to watch out for before I destroy this thing? Thanks.

The engine is Briggs and Stratton, model 31C707-3346.


Just found a video on youtube, how to remove a carburetor. I think I'm ready to give it a go.
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Old 09-16-18, 01:19 PM
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Just take the two screws out that hold the bowl on, not the whole carburetor. There is a tiny brass jet in the center of the white plastic piece inside... get a torch tip cleaner and clean that jet out and replace the formed o-ring around the top of the white piece and the fuel inlet o-ring. Usually that is all you need to do to fix these Nikki carbs. Occasionally you have to clean another jet in the carb, I can explain that if needed. Also make sure the choke isn't sticking... another problem on these carbs.

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