I have a John Deere Riding mower that stalls and found a simple fix. This fix applies to many John Deere riding mowers; my mower is a L120 and I have very steep hills and my mower recently started stalling on me after running it for a short time (5 to 15 minutes, sometimes more).
FYI: If your mower is having problems losing power when climbing hills but doesn't stall, then check out my John Deere Hydrostatic Transmission Fix.
In fact, when my mower stalled on me while riding up my hill, I panicked and tried to turn the mower before a complete stall and ended up flipping it! Yup, it did a double flip and landed right side up! To make matters more confusing, my John Deere started right up (after I stuck the front cover back on).
What I should have done, was not turn, but instead, let the mower just glide back down (it goes very slow without power). Needless to say, it won't happen again. I was also very impressed that after that tumble, the mower started right up - Go John Deere!
I was ready to bring my tough John Deere Riding mower to the shop and have them look at the stalling issue. I was planning on spending about $200 in repairs, but I decided to check some forums for information about the problem.
What I found was that many of the John Deere mowers come with a self ventilating gas cap as mine shown above. This cap has a little hole in the middle which allows it to breath and when that hole gets clogged, it stops the supply of gas and the riding mower stalls!
So, to test this theory, I loosened the gas cap, ran the mower and was happy to find the mower no longer stalling. So, the next time you think your riding mower stalls, John Deere or other, loosen the gas cap and give it another go, you could end up saving yourself $200 or more!