Mikuni heater

[sunquest]

Probably a simple solution, I hope. Switched on the heater at the weekend, the fan operates but no heat, then times out. It hasn't been used for about 6 weeks - any ideas.
Thanks Geoff

 

[andy_wilson]

They sometimes take a while to prime, and if they don't manage it may go straight to shut down cycle.

Just try again. Might help if the fuel level in the tank isn't too low, and the power level in the batteries is well up.

If it repeatedly won't prime, you may have an air leak in the supply pipe.

 

[TrueBlue]

As usual lots of possibilities, 'cos these boxes are quite involved and need lots of electrickery to stop them melting.

My favourite is poor fuel flow, the little pump really struggles to suck fuel out of the tank if there is any air in the system

Second is low battery voltage

Third is duff / blocked glow plug

Anyway those nice people at Mikuni have produced an "idiots' guide" to diagnostics:-

http://www.mikuniheating.com/MX40%20Flow%20diagram-2002_files/MX40%20Flow%20diagram-2002_frames.htm

I didn't know the above existed so I've benefitted too!

 

[SP2]

Hi Geoff

What model do you have? Had some problems with the MY30 like you report and it turned out to be a defective thermostat switch on the bulkhead (after we replaced everything else /forums/images/graemlins/frown.gif)

 

[sunquest]

Thanks for all your advice guys. Yes the fuel tanks are only 20% full, batteries fully charged and I will also check the thermostat switch.