engine backfire.

[maitstoy]

Checked for leaks at the carb base and intake?

you have a fouled plug, my car just did the same thing

 

[injected]

Checked for leaks at the carb base and intake?

you have a fouled plug, my car just did the same thing

x2

 

[t-money80]

got the spark plugs out and all of them were dirty , the electrode and the gap was not that bad , but the top of the threads and down around the outside of the electrode / center of plug had carbon on them but it was real gummy. Recently i had the heads off because i broke a rocker stud , twice and wanted to get the heads checked and make sure i wasn't hitting the pistons with the valves or anything els. everything checked ok on the heads just replaced the studs. The tops of the piston had this gummy carbon on them as did the valves. The guy at the mach/shop said he thought it was sucking oil
from the intake because it had oil in the intake runners. When i put it back together i used some 3m yellow on the bottom edge and smeared some silicon around the ports on top . I checked the plugs after a few days and everything looked good, thought i had it fixed guess not . The guy that checked the heads is the one who did the work on them the first time along with the other machine work . Whats causing this sticky/gummy carbon or oil builed up ? Thanks for all the help.