lawnmower hesitating, using too much fuel

lushgardenerAugust 23, 2009

Hi all,

I'm the proud owner of a 13-year-old MTD push mower, with a 4HP Briggs&Stratton engine. Has worked like a charm throughout its life, until this spring it developed some troubles. While I was mowing one day in rainy weather (don't ask), the mower started hesitating a lot, going to low rpms regularly. This problem stayed, even after changing oil, inspecting the spark plug, starting with a fresh batch of fuel (it contains 10% ethanol around here, but that's not been a problem before). Also, it uses about 50% more fuel than it did previously, which has me concerned that I'm putting the additional fuel up into the air as pollution, by running too fuel-rich. The hesitations occur especially when the mower is changing directions (backward to forward, around a turn, etc).

I took the mower apart once to see if I could find a carburetor adjustment of some kind, but all I found was a little vane at the top fan, which does not appear to be adjustable.

Any suggestions for an approach to get the mower back to prime working order? I'd like to get another 13 years out of this puppy (or at least until I turn enough lawn into garden that I can cut all of it on a single charge of a battery electric powered mower, which I've been eyeing).

Rob

Thank you for reporting this comment. Undo
tomplum

I'm guessing from your description that this is a carb on tank model. There is a diaphragm between the tank and carb. Pick up a new diaphragm kit and intake seal for the tube and with a quick clean up it should be fine. If that air filter is 13 years young, grab a new one as well. Model/type #s would be helpful if you need further info. good luck.

    Bookmark   August 23, 2009 at 3:02PM
Sign Up to comment
More Discussions
Shindaiwa T18 Trimmer TK Carb Rebuild
During the process of cleaning and replacing the diagphrams...
sjsmithjr
Toro Zero turn
Having trouble with Toro Time cutter ZT4200,Koehler...
Amy Bebensee
Need Recommendations For Inexpensive Gas Push Mower With Mulch Bag
I think it's time to retire our old mower, which is...
mimipadv
Looking to replace the LB
I've been using a 2003 Lawnboy 10323 for over a decade...
pacochu
Kohler Knowledge
I am replacing my 2nd B&S 23HP engine on a Simplicity...
wekjo
Sponsored Products
Electric Edger and Trimmer
Overstock.com
Earthwise Cordless Self-Propelled Lawnmower
$419.00 | FRONTGATE
Lawn Pro Lawnmower Hi-Hitch
Overstock.com
Flush 50-Watt Par 36 Well Light by Kichler
$195.40 | Lumens
People viewed this after searching for:
© 2015 Houzz Inc. Houzz® The new way to design your home™