mick55

Turn the heater off, remove fuel pipe to heater and put into a small container, start the heater and in one start cycle it should pump 10ml of fuel until it shuts down. How much fuel did it pump?

I would do a fuel dosing test to see if the pump is delivering sufficient fuel.

After three hours running the temperature should be far higher than 36, around 80 would be more like normal, that heater is not burning at full load.

Let me know how it performs after an extensive run, some part of the system should get hot if the heater is performing correctly, you may have a circulation problem, but this cannot be ascertained until you have run it for a prolonged period, if it is a circulation problem, this can only be addressed once you know the heater is operating correctly I have been installing these heaters for quite a number of years and have some expertise in the repair and diagnosis of them, and that is how I make my living, happy to help if I can. Hope these comments assist.

I should have added, run the system flat out for about three hours, testing for an hour or so is useless, it needs a long run time to see what the system is doing, heating from stone cold takes time, at least one of the rads should be too hot to touch for any length of time, you may have had a new ECU fitted, but even Webasto are not immune to zero hours failure of components, trust me I know only too well.

You say it ramps up well past 50, what water temperature is the WTT actually showing on the graph? after an hour it should be showing 84 at full load before going down to part load, even if the flow is not good, at least some part of the system should be getting hot enough that you cannot keep your hand on it, the whole of the system cannot run lukewarm after an hour of full load, it is just not possible on a small system such as yours.

It should ramp up to 82 degrees then cycle down to around 74, it sounds like the ECU is faulty and thinks the water temp is higher than it actually is. Hope this helps, let me know, I have a good second hand one if you need it.

Cannot use the MCS one as it works on pressure, tank is below engine and virtually inaccessible, piece of nonsense and quite frustrating.

Anybody know how to check the fuel level in a SM Hudson Boat?

can you post a picture of the contacts on the controller?

The Brown wire is the Negative, The Red wire is the Positive, The Black wire is the control, you need to loop from the Red to the A1 terminal to provide power to the controller.

It sounds like you need some professional help, if you are trying to connect a Webasto to a timer you may need Webasto part number 4110553A which is a wiring harness, do not cut the multi pin plug off,this harness lets you connect to the existing multi pin plug on the existing Webasto wiring.

If you are using the heatmiser timer the wiring is: Black goes to A2 terminal, Brown goes to -minus terminal,Red goes to +plus terminal and is linked by loop cable to A1 terminal, hope this helps.

Picture of the one I installed this week

I have installed eight of these units, they are extremely good if fitted correctly, looks like you took the advice on board, lag the rest of the exhaust, this will keep the exhaust system compliant with BSS regs.