IIA 2.25L Backfiring

[dgraham29]

My 2.25L had been running very smoothly, but just started backfiring.
Now I have to engage choke to get it to run anywhere near normal.
Before I go tearing into anything, could it be a matter of ethanol in the gasline?
If so, would a can of dry gas remedy the situation?
Also, is this something that could be seen in glass gasline sediment bowl?
Thanks.

[I Leak Oil]

What carb. do you have?

[dgraham29]

IIA Backfiring

Rochester carburetor
Has new distributor cap, rotor, plug wires, plugs, coil, etc.

[I Leak Oil]

I was expecting you to say it was a weber, classic symptoms. I sounds like a fuel problem. Check the filter if you have one, the sediment bowl and the pickup tube. I'm not too familiar with the Rochester so I'm sure someone here will chime in with what to check with respect to that.

[Tim Smith]

Check the down pipe connection. This is common with a loose down pipe from the manifold as it introduces fresh cold air to the hot exhaust with plenty of hot unburnt exhaust gas.