[John]

Jon, A Webasto needs to be exercised and if not the nozzle tends to get dirty and plugged. They are a relatively inexpensive item and easily replaced if needed. If fuel isn’t sprayed in a fine mist as a result of a dirty nozzle combustion will be affected.

Maybe Rudy can jump in and give a better explanation.

[Archived]

Jon W is right on about running the burner regularly. As the diesel on the nozzle is allowed to sit and sit, it starts to congeal. Once congealed, it will not wash off. If allowed to sit for 6 months, the nozzle may be plugged, spraying no fuel at all.

At first the burner will smell or smoke which gets the combustion chamber dirtier and dirtier. This results in more and more smoke, things are going down hill.

To avoid this situation, you need to run the burner once per month for one heating cycle. This keeps fresh diesel on the nozzle and things will run fine for 1, 2, or maybe 3 years before the burner needs servicing. This means running the burner once per month or more every month whether you need to or not, period.

How to tell if your burner needs servicing? Look at the exhaust pipe while the burner is firing. The exhaust should have a smooth roar, no visible vapor and not smelly or burning your eyes. If this true for your burner, keep on running it. If firing but smelling or smoking, the burner is telling you to look into servicing it sooner than later.

A heating cycle is turning the burner on, allowing it to start and fire bring the coolant up to temp then cycling off.

Common causes for sitting are winter storage or long visits at a shop. So, if this is your situation, plan on stopping by once per month or servicing the burner when you put the bus back in service.

Jon P, the fuel pump in the Webasto burner sucks fuel from the pickup at the fuel tank all the way to the burner. No pressurized fuel till after the fuel pump in the burner. Therefore, the fuel line needs to be air tight all the way to the burner. An air leak will result from white smoke to no fuel and no firing.

If you need personal assistance, shoot me an email with your phone number to jrlegett at gmail dot com. Hopes this helps.

[Jon P.]

Thanks Rudy. As usual, excellent response and explanation.