I got a lawnboy mower from the brother in law. Last time he used it just would not stay running. It has a honda engine.Of course that was 5+yrs ago. Gas still in the carb and destroyed it. Carbs are cheap so I got one and put it in. Has the same problem he had described. It will run for a few min then quit. After some head scratching determined it would run fine with the cap off the gas tank. New cap and all is well. Never came across a bad vent on the cap before.
darn gas cap
- Thread starter jacobsond
- Start date
Common problem because they get plugs with dirt. I blow mine out every time I fill the fuel tank, ED
If you suspect one, you can just leave the cap on VERY loosely (to let air in) to see if that resolves it. Just make sure it doesn't vibrate off and get mowed or lost. It is common enough that I've had it happen on a riding mower and string trimmer. I doubt the string trimmer was from dirt, just age and cheap design vs tight tolerances. Seems more common with equipment made in the last 20 years, before then I rarely encountered it.
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As the fuel is consumed air flows in through the vent and that is where the dirt comes from. Ed
Definitely more common in newer plastic caps. My old Briggs engines from the 70s have metal caps with a hole in the top - no baffle or other membrane under the hole. Very hard to clog them but they also allow some dirt/dust to enter (can see it in the bottom of the tank at the end of the season). The newer designs appear to be better at preventing this, but they also clog more quickly.
