Diesel Heater (Eberspacher/Webasto) fuel advice

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I have an Ebersapcher diesel heater (d2) and I wired it up and tested it before fitting. I had a fuel pipe running into a fuel can, and fused temporary wiring. All worked fine and it generated heat without issue. However, once I fitted it into the van, and had the fuel line (return) on my Citroen Relay conversion tee'd into, it refused to start. A couple of attempts, with either a cold air output, or white smoke from the exhaust. The first time I went out there was diesel dripping from the diesel heater exhaust, even though the heater wasn't in use. It appears that fuel is being forced through the heater and collecting in the exhaust of the heater. For now I've clipped the fuel line to the heater and disconnected the fuse. But, I'm looking for any advice as to how I can stop this fuel oversupply. I would have expected that the pump would not allow fuel through unless it was activated by the heater. So near, yet so far :-(

:anyone:
 
I have an Ebersapcher diesel heater (d2) and I wired it up and tested it before fitting. I had a fuel pipe running into a fuel can, and fused temporary wiring. All worked fine and it generated heat without issue. However, once I fitted it into the van, and had the fuel line (return) on my Citroen Relay conversion tee'd into, it refused to start. A couple of attempts, with either a cold air output, or white smoke from the exhaust. The first time I went out there was diesel dripping from the diesel heater exhaust, even though the heater wasn't in use. It appears that fuel is being forced through the heater and collecting in the exhaust of the heater. For now I've clipped the fuel line to the heater and disconnected the fuse. But, I'm looking for any advice as to how I can stop this fuel oversupply. I would have expected that the pump would not allow fuel through unless it was activated by the heater. So near, yet so far :-(

:anyone:

Do you have the pump wired correctly?

The pump regulates the fuel supply and is pulsed as the heater needs more fuel.
 
I found wiring mine direct to the leisure battery with as short as possible wire sorted my problem of it not starting out
 
if your vehicle has a common rail diesel engine you cannot just tee into the fuel lines as I believe they are pressurised, you need to fit a standpipe into the fuel tank, one way to check would be to disconnect the fuel pipe feed to the pump and just put it into a bottle/jar of fuel and try the heater again bearing in mind it will smoke like hell once started until the unburned fuel has burnt off
 
Do you have the pump wired correctly?

The pump regulates the fuel supply and is pulsed as the heater needs more fuel.
on the eberspachers it doesn't matter which way the wires are connected the pump will still work fine
 
I found wiring mine direct to the leisure battery with as short as possible wire sorted my problem of it not starting out

you are right, incorrect wire sizing can and will give a voltage drop especially on start up causing a fail to start in time fault code.
 
Pressurised fuel lines

if your vehicle has a common rail diesel engine you cannot just tee into the fuel lines as I believe they are pressurised, you need to fit a standpipe into the fuel tank, one way to check would be to disconnect the fuel pipe feed to the pump and just put it into a bottle/jar of fuel and try the heater again bearing in mind it will smoke like hell once started until the unburned fuel has burnt off

I spoke to a mechanic friend of mine (who actually tee'd the fuel line for me) as I wondered the same. He said the common rail is pressurised (high pressure), but the return to the tank is low pressure, and said although he has no experience of connecting diesel heaters like this, he would have though that the pump would prevent it being passed through. I'm really hoping it doesn't need an additional standpipe into the tank, as the thought of dropping the tank and cutting that is not something I'd look forward to. I suppose the alternative is it's own tank, but then I've got to find somewhere for it, that is convenient when filling up :sad:
 
As Fulltimer said it will need its own supply from the tank. Even a low pressure will force the diesel through the valves on the pump.
 
Wiring

I found wiring mine direct to the leisure battery with as short as possible wire sorted my problem of it not starting out

I tried that just in case, prior to noticing the diesel dripping from the heater exhaust, but it made no difference. It's going through the motions, I'm sure it's probably flooded now and that's why it is struggling.
 
I spoke to a mechanic friend of mine (who actually tee'd the fuel line for me) as I wondered the same. He said the common rail is pressurised (high pressure), but the return to the tank is low pressure, and said although he has no experience of connecting diesel heaters like this, he would have though that the pump would prevent it being passed through. I'm really hoping it doesn't need an additional standpipe into the tank, as the thought of dropping the tank and cutting that is not something I'd look forward to. I suppose the alternative is it's own tank, but then I've got to find somewhere for it, that is convenient when filling up :sad:
I can virtually guarantee it will be the problem we had it on a batch of Renault Master / Vauxhall Movano ambulances that we built a good few years back, the first batch were straight forward and worked fine the next were the more modern (at the time)common rail variant which is where our problems came about, it was actually the Vauxhall plant at Luton that found the problem. Fitting the stand pipe isn't too much hassle especially if you have an access hatch through the floor to the fuel level sender unit you only need to drill one hole.
 
Oh well :-(

I can virtually guarantee it will be the problem we had it on a batch of Renault Master / Vauxhall Movano ambulances that we built a good few years back, the first batch were straight forward and worked fine the next were the more modern (at the time)common rail variant which is where our problems came about, it was actually the Vauxhall plant at Luton that found the problem. Fitting the stand pipe isn't too much hassle especially if you have an access hatch through the floor to the fuel level sender unit you only need to drill one hole.

Not what I wanted to hear really, but I was expecting as much. Unfortunately I don't have a floor access hatch as the van is converted now, or 90% anyway. I wrongly assumed that as I tested it, that the connection bit was a formality.

Thanks for all the input :cheers:
 
Not what I wanted to hear really, but I was expecting as much. Unfortunately I don't have a floor access hatch as the van is converted now, or 90% anyway. I wrongly assumed that as I tested it, that the connection bit was a formality.

Thanks for all the input :cheers:

Bit of a guess but you may find there is a spare connection on the fuel tank sender unit. The body builder info for my Ford Transit shows an extra connection on the sender unit for such an application.
 
Bit of a guess but you may find there is a spare connection on the fuel tank sender unit. The body builder info for my Ford Transit shows an extra connection on the sender unit for such an application.

unfortunately I don't think that is the case for the Relay as Eberspacher only list a tank standpipe and no kit for a sender unit , even then you sometimes need to take the sender unit out and drill the connector and often still have to fit a tube inside
 
Not what I wanted to hear really, but I was expecting as much. Unfortunately I don't have a floor access hatch as the van is converted now, or 90% anyway. I wrongly assumed that as I tested it, that the connection bit was a formality.

Thanks for all the input :cheers:

you're welcome, still worth trying what I said in the other post just to confirm the problem, only other thing I can think of is if your leisure battery is a bit low so not operating the glow pin ,to check this you need to measure the voltage at the heater whilst attempting to start the heater.
 
unfortunately I don't think that is the case for the Relay as Eberspacher only list a tank standpipe and no kit for a sender unit , even then you sometimes need to take the sender unit out and drill the connector and often still have to fit a tube inside

Yes checked it, via Relay tank pictures, and specs - there is no secondary feed :-(
 
If you do find room for an extra tank, you could use red diesel, much cheaper, if sourced properly.
 

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