Cameron's mobile service in Tucson stopped by to do a tune up on the AH. He told me one thing I hadn't heard of before, But it made sense.
When he pulled the burner assy off. He showed me what it looked like. There were rather large deposits on the four ports. He then asked if we fueled up with bio-diesel. I said yes, As it's getting harder to avoid the stuff. He said the burner and the way it comes set up from AH is designed to run on #1 & #2 Diesel.
It is a fact that Bio-Diesel does make more ash. In our M11 it isn't a biggy.
So that makes sense as to why the burner in our AH was quite messy. The deposits were about .5" high right next to all the ports. Which can make the swirling action of the ports diminished and burn less efficiently.
Pulling the burner chamber and cleaning it with a wire brush is part of regular maint. New nozzle, clean the flame sensor and check ohms, adjust points on the starter, new fuel filter too. Rudy has a box that lets him test all of the control functions, spark starter, fuel pump, blower motor, fuel solenoid and more. Whether you do it yourself or have someone else help, it is good to know how to do a basic service and have the parts if you need to do it yourself.