Very embarrassed to be here. Been doing lawn mowers for over 55 years. Never been stumped before. As "they" say...there's always a first time.
John Deere JS 63 with Briggs Intek 6.5 model 121602-0269-E1. Approximately 20 years old. (a guess that) Owned this mower since new. Always indoors overall pretty good condition. Low hours.
In mid February stepson started mower and did back yard (very heavy growth). Mower worked fine. About March 1 I got mower out and did a 5 min patch of grass so that I could get to a fence. Mower started but stalled. Restarted and when started to stall pumped bulb and it came back did this maybe 3 times and mower worked well after.
Took mower out to mow about March 17 and start and stall, start and stall until one gets tired. Only responds to primer about 1 time in 3 or 4 tries.
Have tried starting fluid and it runs for maybe 5 seconds. Have cleaned carb (carb spray not soaked), replaced gaskets from head out. New plug, new gas cap, new primer bulb installed fuel shut off and a fuel filter along with new fuel line. Changed oil. Fuel tank was off and sloshed fresh fuel around and out filler hole. There is no evidence of contamination or blockage. Fuel ran freely when pulled line from carb. Tested spark good blue and jumps about a .100 in. gap.
It ran once for about 7-8 min then right back to start/die pattern. Tried to check compression but forgot about compression release....
Have done what I can in searching archives did not find anything helpful.
If this came into the shop, I would start by rebuilding the carb and replacing the float needle and seat. Part number 398188. Also make sure that the primer, fuel cap and float bowl vents are all open.
