Wallas paraffin heater fuel pump

[WindermereColvic]

I'm investigating why our Wallas 2400 isn't working.
During operation, the fuel pump don't make a sound. Would you expect to hear a clicking like eber fuel pumps?
After disconnecting the pump outlet and priming the paraffin feed and running for some time, no fuel appeared to be pumped.
Finally, after removing the pump completely and flashing across 12v, no clicking or indeed anything else can be heard.
So, is the pump jiggered? Anything I can do to bring it back to life?
Are they a specially calibrated metering pumps, or can i replace it with any old pump?

Also, i'm always reading when it comes to these things the combustion chamber should be kept clean. Photos of wick and combustion chamber below, is this clean enough?

Thanks as always,
Matt

 

[earlybird]

My Wallas 1800s pump makes a subdued, but definite click approx. 1 per second.
I've never really investigated it, so can't really suggest further.
Kuranda are very helpful.
BTW, there's a filter on the suction line, have you checked that?

 

[Kelpie]

The pump is indeed a special metering device, and apparently you cannot substitute a different one.
My own Wallas gave up the ghost last year, no spares anymore according to Kuranda

 

[John_d_Smith]

I'd start by checking if you've got continuity through the coil. I once had a solenoid tha had a thermal fuse wrapped to the coil which would blew if things got too warm.

 

[smeaks]

I overhauled my 1800 this year the combustion chamber you have is clean the soot and carbon on mine was around the wick. The service kit provided new igniter and wick material.

You appear to no igniter coil left other than that it looks very clean.

The pump should click and does so even without fuel so that is a problem. To be honest if you cant find a wallis one i think because it is an inle pump and relies on excess fuel draining from the burner back to the tank then i you should be able to replace it with another brand eg like an eber.

when mine cycles it pumps as long as the card feeds the pump 12v so it should be ok as long as it does not overload the wick. When running at half power it just ticks slower!

I think you should be able to get the delivery volumes of each pump and compare. The drain runs with air bubbles in it so the delivery is not flooding the wick.

treat with caution when commissioning and i think youd be ok.

regards

smeaks

 

[BabaYaga]

Anything I can do to bring it back to life?

The standard trick to get these back to work is to gently tap them with the handle of a screwdriver or similar. This is to overcome the effect of corroded breaker points, I believe.

 

[smeaks]

as baayaga

found this regarding eber pumps

"I had a chat with a helpful chap on the Eberspacher stand at the boat show last year. He said the most common cause of non starting was the fuel pump sticking. The Eberspacher control unit fires a few pulses to the pump at startup. If the pump doesn't respond, the unit shuts down. The cure is to disconnect the power connection on the pump, connect a couple of wires to the battery and 'flick' these onto the pump. A few pulses like this normally get it working and you'll hear it clicking. If not, give it a few taps with a hammer.

Worked for me, hope it does for you."

 

[WindermereColvic]

The plot thickens..
I took the fuel pump to bits,cleaned it and now tada! when its flashed across a battery it pulses. However, when the pump is connected back to the PCB, it doesn't tick.. Measuring the voltage at the pump with the heater on, I get a constant 4.5 volts or so. Now I guess it should be getting 12....0....12....0 etc..but it could be that the pulses are too short for my multimeter to mesure...
Not sure where to go next!

 

[smeaks]

The plot thickens..
I took the fuel pump to bits,cleaned it and now tada! when its flashed across a battery it pulses. However, when the pump is connected back to the PCB, it doesn't tick.. Measuring the voltage at the pump with the heater on, I get a constant 4.5 volts or so. Now I guess it should be getting 12....0....12....0 etc..but it could be that the pulses are too short for my multimeter to mesure...
Not sure where to go next!

try it with the engine running to max the voltage and then give it a little tap... the attitude of the pump in the fixed position could be different enough from test to allow it to stick. persevere these heaters are very good mine heats whole cabin in about 15 mins.

 

[David2452]

I guess it should be getting 12....0....12....0 etc..but it could be that the pulses are too short for my multimeter to mesure...

You have guess incorrectly, a common misconception is that you will get a c12v 0v c12v reading from an ECU (or PCB as Wallas call them) pump output, you will not.

 

[WindermereColvic]

You have guess incorrectly, a common misconception is that you will get a c12v 0v c12v reading from an ECU (or PCB as Wallas call them) pump output, you will not.

Thats interesting, thanks. Any ideas what I should see? Or indeed the correct way to test that function of the PCB?

 

[aquaplane]

Mat, sent it to Kuranda, they aren't robbers, and it will work when you get it back.

 

[David2452]

Thats interesting, thanks. Any ideas what I should see? Or indeed the correct way to test that function of the PCB?

The readings you get will be dependant on the quality of your measuring kit, most will not keep up with the pulse, I use the diagnostic software but a known good pump is also a good test. As mentioned above if you send it to Kuranda they will sort it for you.

 

[Hencha21]

I realise this is over two years ago but current readers may not be aware that there is an overheat trip switch. I certainly wasn't when I started looking at mine.

On mine, an 1800S sail version24 years old, the switch is on the right hand end beneath the heat duct and is a button in a red rubber cover. Whenever I try to start, if the pump can't be heard clicking, then most likely this button needs clicking back in again.