burner problem

My 12 volt burner is cutting off about 1 minute after i pull the trigger. I have eliminated the fuel pump,fuel soliend,hi limit switch,pressure switch,low oil cut off. I have a new fuel filter. Anybody have any ideas what to look for. I usually dont have problems diagnosing problems but this one has me scratching my head.

Check the fuel line, if it is old it could be collaspeing and not letting the fuel flow. It is a good idea to change it every couple of years, not that expensive anyway.

Had one like this the other day it was the HV Transformer. Another thing it could be is sediment in the fuel tank it will pull over the opening when running for awhil and stop fuel flow when you stop it will float up then it will pull down repetedly. Clean out the fuel tank>