Originally Posted by Oilrag
Originally Posted by Zaczac
Now on a side note I have had manifold off recently and was unable to source a new gasket so put her back with old one. Is it possible once heated there was more of an air gap somewhere? causing backfire?

I had a backfire/pop through the carb.
Problem was my intake manifold moved out of position
just enough to cause the popping in the carb.

PO did not use the intake sleeves to properly align the manifold.
I installed sleeves, new gaskets and no more backfire/popping.

Yeah i read that gaskets could cause it and i think it is a likely issue as the old gasket was crap but had no new one at time (just ordering one today)
It makes sense to as it only did it once warmed up after metal expanded.
Either way truck is very old and carby leaks so planning on doing carby and gasket in about a week and will see.

I checked points and very good cond, and bought new condensor too.
J