tips on bleeding a heater system

[symondo]

Had a bit of a breakthrough today!
I discovered the fuel inlet though was for the heater... Isn't.
I did however find the right 1 with a part clear pipe and I can see its.now drawing any diesel through.

I need to check the filter but don't have anything to undo the filter housing to check it yet.
Once I've done this, what is the best way to purge it?

I'm guessing if I let it try and draw it manually the heater will shut down, therefore not draw diesel through

 

[pcatterall]

Had a bit of a breakthrough today!
I discovered the fuel inlet though was for the heater... Isn't.
I did however find the right 1 with a part clear pipe and I can see its.now drawing any diesel through.

I need to check the filter but don't have anything to undo the filter housing to check it yet.
Once I've done this, what is the best way to purge it?



I'm guessing if I let it try and draw it manually the heater will shut down, therefore not draw diesel through

What kind of heater is this? If its an eberspacher type then 'bleeding' is not quite the right term. Once you are sure there are no obstructions the just try to start the heater. It may need a couple of attempts depending on the length of pipe but eventually it will draw the fuel through.

 

[AngusMcDoon]

With an Eberspacher the pump can be operated with flying leads with 12V on them. Connect the grounds together, and then briefly stab the other terminal with the 12V flying lead. You need to find out which of the connections on the pump is ground and which is 12V, but this can be done with a voltmeter when it is operating or a continuity test to ground on each terminal when it isn't. The flying leads should have a fuse inline, just in case they accidentally touch together. An inline filter can take ages to fill as the amount of diesel pumped on each cycle is minute. I prefill my filter with a syringe and a needle through the outlet. I have bled my heater fuel system like this a few times now - every time I change the filter. I don't want to risk lockout by exceding the maximum number of false starts.

 

[symondo]

Its a Webasto air 5000 heater unit.

Currently it shows a non start error code - probly as theres no fuel in it. I had initially wondered if it was a glow plug but this seems more likely as I cant see anything being drawn through the system.

I'll try and get the filter housing apart, check it out and then see if we can draw some fuel through it manually as described. a set of leads onto the pump sounds like an easy enough plan

 

[AngusMcDoon]

Its a Webasto air 5000 heater unit.

Currently it shows a non start error code - probly as theres no fuel in it. I had initially wondered if it was a glow plug but this seems more likely as I cant see anything being drawn through the system.

I'll try and get the filter housing apart, check it out and then see if we can draw some fuel through it manually as described. a set of leads onto the pump sounds like an easy enough plan

I'm not familiar with the Webasto pump. The Eberspacher is solenoid operated and requires pulses of power. The Webasto one may not be the same.

 

[NormanS]

It's another opportunity for some dinghy pump technology. Slacken off the joint at the pump, stick a duster in the pump air vent, and apply dinghy pump to tank inlet. Pump gently until fuel appears at the slackened joint. Bingo.

 

[David2452]

Bleeding is not really the correct term, it's priming, but that's unimportant. I either use the prime command on the software or a simple pulse generator if I am not using the software but again that is unimportant to you other than if you are close by I can lend it to you if only over a weekend. The simplest method is to just let it run through several start attempts which will prime it if the tube is not too long. Unless of course the filter is really large, in which case I would fill the bowl first. But, before any of that make sure the fuel tube is not blocked by blowing back down it (from the tank side of the pump) with a bike pump or computer dusting aerosol.

 

[Alpha22]

by blowing back down it (from the tank side of the pump) with a bike pump or computer dusting aerosol.

Beware, dusting aerosols are often butane gas.... you would think twice about blasting your gas cylinder into your bilges!!!

 

[David2452]

Beware, dusting aerosols are often butane gas.... you would think twice about blasting your gas cylinder into your bilges!!!

Indeed, use a freely available air one, I have to confess I have used a gas lighter refill in emergency, but through a long tygon tube from deck level, but I know even then its not big and its not clever.