nu way boxer

[smitty]

Was called to a nuway boxer pressed reset burner fired runs for few minutes then starts to mis fire but keeps going through cycle starts same thing until chokes it self out ,changed box,coil thinking possible water in oil any suggestions?

 

[SimonG]

What fuel pressure? and is it constant.

 

[Best]

Really should check the oil is getting to it & clean. As SimonG suggests, put an oil gauge on pump to watch the pressure. Oil flow sounds likely.
The plastic motor - pump drives can be worn, especially the oil pump shaft side, on boxers.
This is all assuming the boiler is clean inside?

 

[hasbean]

you need to check flue and air ways by the sound it.

 

[bright spark]

I'd go with Best and check the fuel pressure, i.e. are you losing pressure as the burner runs. Could be fuel filter or even a slight blockage in fire valve or a kinked flexi line. All the best and let us know how you get on.