QuestionI have a troy bilt pony tiller with a 7hp briggs intek engine. It will start fine the first time, revs up and idles for roughly 2-3 minutes then starts to die, if at this point I increase the choke it will stay running longer but only for a few seconds then I have to increase the choke more to keep it going until I max choke then it dies. At this point the starter rope has to be pulled twice and will usually start on the third pull or forth. Once started the second time the engine revs up and dies within less than 30 seconds typically. If the engine is left for 5 minutes or longer it will go through the longer run/slow choke process. I have taken apart the carb and checked that all the holes are open (it is clean inside with very little residue), I have loosened the main jet nut with no effect (float type carb). Gas has been emptied and replaced with new I even emptied the gas tank from the fill hole to make sure no large particle could be clogging the fuel line, gas line is clear and fuel flows freely. Carb consistantly has fuel in it when I take it apart. Oil has been changed.... I am at a loss from my observations I would bet it is fuel resriction somehow but I am not sure how, my next step is to buy a carb rebuild kit to replace the fuel inlet needle and gasket. Thank you for any help you have to offer.
AnswerTry running it with the fuel cap loose, if it is not venting, it
could be starving the carb.
But otherwise, I would suggest that you need to check your valve
adjustment, it sounds like the clearances have gotten out of whack,
and there is little or no clearance on your valves, and when they heat up and expand, the engine loses compression, and choking helps only for a little bit.
Checking the clearances is not hard to do, but will require
a set of feeler gauges. It is a common problem on Briggs OHV
engines. But check the fuel cap, and let me know.
Fish
