single
Well-Known Member
After some testing i have established the fuel pump is u/s on my 12v airtop 3500. Are these fixable or has anyone got a spare one kicking about? Are they the same as Ebers etc?
Webasto fuel pump
- Thread starter single
- Start date
sailorman
Well-Known Member
eba not the same, the "dosing" should be set for Co2 emissions according to the hand book ( if the ole memo...)
savageseadog
Well-Known Member
You can use an eber pump meant for a similar size heater. The electronics regulates the flow, ie click rate for the pump for the heat setting so ml/pulse is not too critical but should be sensibly near. It's possible to measure flow rate by simply filling a pump and line, manually powering the pump with 12V pulses and measuring the output for 10 pulses.
David2452
Well-Known Member
You could try an Ebo one but it is vital to test and set the CO2 values to ensure that the pump is delivering the correct dose otherwise you could wind up coking the thing up or overheating it, all in all not the best solution. Best thing is to get the proper Webo one (even then the CO2 should be checked after fitting) The Airtop pumps are all the same, it is merely the pulse rate that varies (nothing to do with the size of heater) so one from an AT2000 or a 5000 will also do the job, I'm sure have a few good used ones about the placeand will have a look, are you (or rather is your boat's system) 12v or 24v?
PM me if you like, or my contact details are on the Webasto site.
PM me if you like, or my contact details are on the Webasto site.
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farelo
N/A
No it is not the same.thanks for sharing
Keith-i
Well-Known Member
Is it definitely u/s or just clogged? Although theoretically not serviceable, I found a small gauze filter behind the inlet pipe. I removed this and fitted a small outboard filter ahead of the pump.
Oceanmaster
Well-Known Member
It happened to me
If the unit clicks when you remove and restore the power to the unit then it is working. however if you get no fuel through (about a tea spoon each click) then probably have a block in the capilary tube. the capilary tube is tiny. carefully stick fine stiff wire down the hole in the centre and waggle...restore and remove power and the unit clicks pop the input into any fluid and the power of the clicks will remove the blockage. watch out the fluid fires out of the pump along way. I you clear the blockage and it works again refit with a filter. Give this tip plenty of goes. the pump is designed to be as tuff as old boots. however it is sealed and costs a bomb to replace. I do think they are availabe on ebay.
good luck
If the unit clicks when you remove and restore the power to the unit then it is working. however if you get no fuel through (about a tea spoon each click) then probably have a block in the capilary tube. the capilary tube is tiny. carefully stick fine stiff wire down the hole in the centre and waggle...restore and remove power and the unit clicks pop the input into any fluid and the power of the clicks will remove the blockage. watch out the fluid fires out of the pump along way. I you clear the blockage and it works again refit with a filter. Give this tip plenty of goes. the pump is designed to be as tuff as old boots. however it is sealed and costs a bomb to replace. I do think they are availabe on ebay.
good luck
Tomahawk
Well-Known Member
Tad more the than my experience.. Mine puts out a drop per click not a teaspoon. Thinking about it I don't even think the fuel pump delivers a teaspoon worth of fuel until you get to about 2000 hp..
Separetely, be very careful about getting dirt into the fuel inlet to the unit. I am told that is terminal as once the inlet is blocked there is no way to clean it!!
Steve Clayton
Well-Known Member
As said by others if you can hear it click then it's probably OK. There is an inline fuel filter; if genuine Webbie filter then you can't service it or even see if it is blocked (as was mine). New filter is about £25; or pick up an inline, see-through filter at Halfords for about £3
single
Well-Known Member
It wasn't even clicking.I will go down later and play with it.
Before i go down there does anyone know what the pump part number should be?
Before i go down there does anyone know what the pump part number should be?
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single
Well-Known Member
Been there and big bang on the pump and it worked fine.After about an hour on max the fault code come on (6 flashes) which is temp sensor so now what?At that point pump stopped but i assume the sensor fault shut it down?Thanks David.
David2452
Well-Known Member
Is it six flashes or one flash? i.e. five rapid + 1 or five rapid + 6, if the latter then check for "bright & tight" connections to the sender, if no result from that then replace the sender. Remove the fuse for a few seconds and replace it if there have been numerous no starts. Pleased the good bang we spoke of in PM worked though, it usually does when they are just stuck because of lack of use, like not running for 20 minutes a month even during the summer.
single
Well-Known Member
Its 6 long and a fast burst.Try again tomorrow.How can i check the ext. temp. sensor?Other question...it says temp. sensor fault but which sensor? the one in the heater or the ext. cabin air temp. sensor?
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David2452
Well-Known Member
It means the internal one, it can be checked with a Megger or Avo, specs are in the manual.
single
Well-Known Member
Hopefully.....thats the cheaper one isn't it? Got a megger so will check.
David2452
Well-Known Member
Part # 88510C about £20 unless you have an external one, those tend come to with the boat kits so it could easily be an external one. You may find if somebody has installed a seperate external sensor they have some kicking around as you remove it to fit those, I will check if I have any though I usually leave them with the customer,
single
Well-Known Member
Was there all day again ready to strip it but it worked fine for a while then same fault again.I have got hold of a internal sensor but mine also came with the little cabin air temp sensor.Anyway how easy is it to change the internal sensor?
David2452
Well-Known Member
If you have an external one then there will be no internl one as the external one plugs in the same socket, take off the small cable access cover from the top clamshell, remove the plug for the external one you have and replace with the internal one, five minutes if access is OK. One piont I would mention is that in the past I have had a few temperature sensor faults indicated by both the diagnostic flashes and my Thermotest diagnostic kit which replacing didn't cure and the eventual fault was the ECU. Also crank the control element up to maximum when checking it then if it runs OK for a couple of hours turn it down gradually to see if the heater reacts.
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single
Well-Known Member
Right, back on board with laptop this time! I just changed to a new internal temp sensor and it ran ok for about 10 mins then started blinking 10 flashis indicating overheat.Left it a while tried againand the same. Played with connections and its running now but anything else i should be checking? It now shuts down after about 10mins but runs again when turned back on.
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Tomahawk
Well-Known Member
If it says it is overheating. It may simply be blocked ducting or lask of inlet air
Can you run it with no inlet and outlet ducting?
That will confirm if you have an installation issue with too much back pressure?
Good luck
Can you run it with no inlet and outlet ducting?
That will confirm if you have an installation issue with too much back pressure?
Good luck