gas supply (?) problem

[Dave-Saratoga]

can't figure this one out- i just replaced the 10-horse engine on my b-210 with the 16-horse model. Everything worked fine with the 10-horse installed. When i mowed the lawn the other day for the 1st time with the 16-horse on, as i continued and the engine heated up, it would occasionally sputter, like there was a fuel problem. the sputtering increased until it eventually stalled. i let the tractor sit & cool down for about an hour (while i enjoyed a cold beverage). when i went back the tractor kicked right over and ran fine. i continued to mow the lawn only to find that the problem repeated itself. there was however and additional hitch - it was starting to get dark so i decided to turn on the light to finish. well, they worked fine for a few minutes, then they dimmed and went out. i turned off the switch, then immediately turned it back on - the lights were fine again, until they dimmed and went out again (they were on for a bout 30 secs, then faded for about 30 secs). shortly after that, the engine started sputtering and then died. - frustrating:(! this time, i noticed that the gas tank was down to about a 1/4 full, so i added fuel and for some reason decided to try to start the engine - it kicked right over, about 5 minutes after it had stalled. any possible suggestions as to what the problem is here? i'm fairly stumped.

[SmilinSam]

Sound more like an electrical problem rather than a fuel problem. First thing I 'd do is get the meter out and start testing for shorts in the switches and wiring. Also would try a new plug too( I say that because I have had a couple of instances where that was the last ting I looked at and that was the problem, not to mention its not costly and take little time.

[Al]

Hi, First I would replace the plug. If the problem continues, as soon as it dies I would immediately take a test spark plug and unplug the plug wire and connect it to the test plug and see if you have spark. DO NOT ALLOW IT TO COOL FIRST! If you have no spark you have an igniton problem. Does the engine blow black smoke before it dies? If it does, I would expect the carb is getting overheated from the muffler. In the 80s and early 90s we had a lot of problems with this. The gas was reformulated and we had to build heat shields on a number of tractors. We have not seen much of this in the last few years, but it is common if you are burning gasohol. (10% Ethanol) The problem is common in the 3400 700 7000 series when the muffler is not well lined up with the hole in the hood or the exhaust pipe is broken from the muffler. The exhaust then blows out around the carb and when it boils the gas in the carb, black pours out and the engine floods and dies. Problem can also be caused by a sticking valve. The symptoms are also similar and when the engine cools the valve works again. Sometimes you can hear a clue when the engine dies and winds down, one may notice the engine acts as if it has no compression. The fix remove the valves clean the guides with solvent and a wire brush and wire wheel ALL the carbon off the valve stems. Gring the valves and put it together again. Good luck, Al Eden

[dlcentral]

Good post Al, how do you check coil with an ohm meter also,isnt it supposed to be like 20-60 ohms from shutoff tab to ground? thx dlc