$ircra$halot

Thanks Dave.
I thought I had guessed the gap close to right. this engine is an older one that I inherited from a friend that passed last summer, I have no idea how old it is, but I know it has never been run. Here is another Question! I started it yesterday for the first time, it seemed to run great through the first 1/2 tank of gas, (approx. 8 oz). running at 170 to 175 degrees at the base of the cylinder head, carb. side. It was run at full throttle 3 times, approx 10 seconds each time to approx.5800 R.P.M. the rest of the run was at idle (Zinger 22X8 prop). I then shut it off and flew my tiger 60. However when I tried to re-start it about 45 min. later it would pop when choked after 3 or 4 flips, choke off, 3 or 4 flips it would start and run for 15 to 20 seconds only, we could get it to stay running by choking it while running, this suggest to me a fuel draw problem, maybe the pump diaphram dried up after sitting for possibly 20 years or more, but it did run for 15 to 20 min. on the initial start. It eventually got to the point where it would not even pop, the ignition battery still shows 5.4 volts. Any ideas?
Thanks for any help
$ircra$halot
Garry