Questioni had a tune-up done last year on my sears riding mower. everything seemed fine for a while then the mower would stop after about 20 min. sometimes i could get it restarted right away and then sometimes i ould need to wait about an hr or so. it should not do this. any ideas... fuel pump?
AnswerThese are the toughest problems to fix.
I would start by purchasing a new spark plug(s). When the mower stop, hop off the seat and change the spark plug when it refuses to restart.
Some odd things I have run into over the years that can cause you problem:
Gas cap not venting...vacuum forms in fuel tank and will not allow fuel out until enough air enters tank
Electric fuel-shut off solenoid closes when it get the engine heats up and stops gas from entering the engine.
Some safety switch or switch connecting not properly working when hot...this one took me several weeks to fix as the problem did not happen very often...when the connection failed is was the same thing as if you got off the seat and the engine stopped.
All of the above are rare but I've had them happen so I always check when a customer has a similar problem such as yours.
Do you have to be mowing for the problem to happen?
Can you drive the mower for more than 20 min and not have the problem?
First thing to isolate is to verify if you have a spark or fuel problem. Do you have an inline spark tester to verify you have spark when the mower stops?
Eric
