It does look like the one on the outside is marked 0-40uf and trying to find a rough translation of the text towards the bottom gives me the impression that it is 40uf for the first 1.5 seconds then reduces to possibly 0 when the motor is running. The time that this can be repeated is every 6 seconds possible with the lower line. So the 60uf in one @mm289 would be the correct one and the 0-40uf on the outside is just used when the motor starts. Like having a centrifugal switch inside a motor but without the additional cost of fitting the switch. So at start his would be 100uf then once the motor has started it would then reduce to 60uf. The one I have here does measure 40uf but I’m not sure how it could be tested when operating
Thanks @carbon that's great info. I think I will start by replacing the 60uf as that looks a bit battered anyway and see if that fixes it. I saw on the pic of my external cap that it was noted as 0-40uf so your thought of it being a start cap makes sense although I am no expert on this
Thanks for posting the wiring diagram, I am sure that will help when I inevitably find a thermostat or something is kaput as well
I've had a quick google search and I'm struggling to find a similar capacitor, I could be using the incorrect search term. All the ones I've found are just plain 40uf caps. If that 0-40uf is no longer available it could be replaced with a electronic motor start capacitor relay and a standard 40uf capacitor as it seems some of these relays have an adjustable timer
Got the new 60uF capacitor this week from RS and fitted it today. Bingo, started up straight away
Reassembled motor and re-fitted then coupled everything up. Its too cold and wet to try again today but might have a go tomorrow. With the pump and motor now fixed next job is to see if I can get it to produce flame
what fuel are you using tractor diesel or heating oil mine will only run on the lighter fuel otherwise it soots up and runs crap. if i have to use tractor i dilute it with parafin
As these machines use a pressure switch to signal the delay board to energize the fuel solenoid you may need to have the nozzle connected to the trigger for that to work.
There is a small filter in the fuel pump that may need cleaning
@brightspark it previously was running on red diesel, I have just drained all that down and filtered and will probably mix with some kero or new diesel when I rebuild - we have oil heating so its quite easy to drain of some kero - its what I use in my home made Eber workshop heater
@carbon Yep it has to have the pump running, when testing previously I mimicked that by depressing the plunger in the pressure switch and got it to squirt diesel that way
Thanks for the tip on the filter, didn't know that - it has an inline fuel filter as well but thats pretty cruddy
I think it needs to be correctly orientated to fit back together, rotate the filter when refitting it then fit the cap afterwards
A lot of fuel pumps have internal filters, some larger than others some more difficult to find. Some can look worse than this one
Not sure how they expected this one to work
All reassembled and runs fine, but struggling to get it to ignite.
First up the electrodes sit at the side of the nozzle and don't seem to be near enough the mist to ignite it.
Also the electrodes will only arc if really close together, like 2mm and they are arcing only between the end of the shafts not the tip, which I think is because the arc isn't strong enough to bridge the larger gap between the tips.......
You can see the arc if you look closely at the pic below and also the diesel mist
So whadya think? Wrong electrodes, new electrodes, new coil.......... so close but so far
Only on my phone so can’t see the picture to well but nozzle needs replacing to start as doesn’t look to be spraying very well. When the top of the burner is back in place the air flow over the electrodes will move the spark off the end of them.
pull the leads of to the electrodes hold them apart and fire up see how far the spark jumps if its a good distance its the electrode insulation has broken down and shorting
what fuel are you using tractor diesel or heating oil mine will only run on the lighter fuel otherwise it soots up and runs crap. if i have to use tractor i dilute it with parafin
I used to service dozens of Karcher hot washers being used at car washes & farms & this was our customers findings.
Running them on just heating oil gives a clean burn but it doesn't have the lubrication properties of diesel & your fuel pump will wear out quicker plus they don't get up to full heat.
Running them on diesel gives better heat & the pumps last longer but the boiler cokes up quicker.
Running them on a 50/50 mix of heating oil & diesel gives you the best of both worlds, good heat, a clean boiler & good pump lubrication.
It sounds like yours is running to rich on diesel, you might need to give it more air or lower the fuel pressure to get it burning cleaner. I used to be able to set up the boilers using just my nose & eyes on the exhaust to set the air/fuel mix, then stick on the gas analyser to give the final check & printout that some customers required.