I have a WeilMclain boiler with a becket burner. It seems to run fine when warming the house to tempurature will cycle on and off with no proble.
Lately I come home and the boiler is out. I push the reset and it fires right up.
It started doing this every 4 days now it is every day.
Recently upon start up it had a hard time firing. Once the fuel ignited it sputtered and smoked. Once again after it ran it cycled on and off fine while warming the house.
I have changed the filter. Cleaned the pump screen and checked the nozzle.
I have read that agravity feed on these models could cause problem. It may be my imagination but it seems the more I have done to correct the problem the worse it has gotten.
Any help please...

I suggest you go to the Weil McClain or Beckett site and obtain the proper manual for your EXACT burner then research from there. Many different problems can be the cause of the exact problem you are having. Guessing at burner problems just makes it worse and much more expensive.