Member Since: 04 Feb 2012
Location: Scotland
Posts: 166
sorry, another FBH question
Hi All
Having searched and read all I think are appropriate threads I am still at a loss, I have removed the FBH, followed Robbies cleaning process, reinstalled, tried with and without air con, I am getting smoke on start up then nothing, checked codes and the code below shows every time, I did the test procedure, primmed fuel (all OK) but on starting the engine, smoke then nothing, the good news is, before cleaning it just locked out, really would appreciate help, at a total loss, thanks.
Discovery 3 SE gone but not forgotten.
Discovery 4 HSE (Mrs S)
Discovery 3 GS project, great, but manual, Gone.
Discovery 4 XS
29th Dec 2020 2:54 pm
azurar01
Member Since: 24 Feb 2011
Location: Gloucestershire
Posts: 509
Member Since: 24 Dec 2020
Location: Norway
Posts: 107
Its probably the diesel pump that has problem this works on frquency sgnals Hz from fbh module.
If it smokes at least glow plug works and probably also the fan but if the pump can not give enough fuel it will blow out the flame.
Component fault is the clue here providing you get it correct back together after cleaning.
29th Dec 2020 5:43 pm
davecars
Member Since: 04 Feb 2012
Location: Scotland
Posts: 166
Hi azurar01
Yes I re-read it twice and re-checked but to no avail.
Hi Kviasen
My thoughts also, as I did try a second hand FBH, when fitted I had the same result as my original unit, (original unit was refitted), next question is how to prove and rectify the problem if it is the diesel pump, bearing in mind my strength is mechanical but only ok when it comes to electrical systems,
Many thanks.
PS, must add this is for my D3 not my wife's D4 if that makes a difference.Discovery 3 SE gone but not forgotten.
Discovery 4 HSE (Mrs S)
Discovery 3 GS project, great, but manual, Gone.
Discovery 4 XS
29th Dec 2020 8:39 pm
Kviasen
Member Since: 24 Dec 2020
Location: Norway
Posts: 107
I am sure there is nothing that can be calibrated, the diesel pump metering is fixed aginst the blower fan speed.
When heater is started the fan makes a purge to remove gas or flamables before the fan reduces speed, turns on glow plug and fuel pump and makes a start attempt.
If the temp is not raising in the chamber the electronics is sensing a faulty start attempt and make another one and another one until it locks up and throw a fault code.
If the elektronics sensing temp raise the heater will balance air and fuel mixture after a preset curve until full power.
My guess is diesel starvation since a air starvation mostly would lead to a lot of black smoke or greyish thick unburnt diesel smoke.
The pump sits under the car in front of diesel tank and is quite easy to replace but remember to get exactly the same pump as put there originaly or you will have problem because the electronic depends on that when a certain Hz is sendt to pump the exact measured amont of diesel is supplied.
Someone before you can have had the pump replaced with inncorect pump so check for that.
To try to test the pump you would have to generate a Hz sinal and from webasto technical departement get a curve of ml pr minute of diesel at that frecuency and exactly measure it in a measuring cup, this would be complicated to achive with normal equipment in the garasje.
29th Dec 2020 9:22 pm
davecars
Member Since: 04 Feb 2012
Location: Scotland
Posts: 166
Thank you for the quick reply
Well explained, and easily understood, it certainly seems to point to the diesel pump, I'll hunt around and see if I can get a proper part number for the pump, got to give it a go as at the moment it isn't working, again thank you Kviasen.Discovery 3 SE gone but not forgotten.
Discovery 4 HSE (Mrs S)
Discovery 3 GS project, great, but manual, Gone.
Discovery 4 XS
29th Dec 2020 9:38 pm
Martin Site Admin and Owner
Member Since: 06 Nov 2004
Location: Hook Norton
Posts: 18567
Could be blocked inlet to the dosing pump, can be blown out with an air line. Can't be done at the FBH end through the pump, remove the inlet hose from the tank and blow back in to the tank.
Definitely been covered here before 06 D3 SE / 15 LR D90 XS SW / 88 LR 90 Td5 / 68 BMW 2000 ti
Any issues with the site let me know!
29th Dec 2020 9:52 pm
Kviasen
Member Since: 24 Dec 2020
Location: Norway
Posts: 107
Glad to be at help Davecar 😎
29th Dec 2020 9:59 pm
Motolab
Member Since: 18 Oct 2019
Location: Sleen
Posts: 1820
Re: sorry, another FBH question
davecars wrote:
I did the test procedure, primmed fuel
Did you do the complete running test with your IID?
You can let it run for lets say 10 minutes (NEVER do shorter runs!) with IID.... if it does then the dosingpump is ok...
I read here different diagnosis, but if it runs in test mode ok, the FBH and its components are ok....
Seen it too much, people starting to exchange components, etc...
Dosingpumps, work or don’t work... seldom or never seen one in 15 years who did work partially....Best regards
Harold
Always looking for Pre '55's & Pre war British Motorcycles! knowing or having one for sale? PM please. I visit the UK 6 times a year
Ps. I edit my texts quite often, english is not my native language, so I will edit My “typo’s” etc.
30th Dec 2020 12:02 am
Kviasen
Member Since: 24 Dec 2020
Location: Norway
Posts: 107
Motolab is probably right, parts are many times exhanged just for testing but the problem is often elsewhere and thats why i suggest that there could have been a problem in the past where the owner had some issues and replaced the pump but with a faulty or maybe incompatible pump.
So Davecar should indeed check the pump against original numbers to his specific fbh make and model but not neccesarely replace it.
A cheap knock of could easily be the problem since there are no tolorances i belive from Webastos/ Land Rovers own setup.
30th Dec 2020 9:49 am
davecars
Member Since: 04 Feb 2012
Location: Scotland
Posts: 166
Hi motolab
When I reinstalled the FBH after cleaning I did the IID test, fuel primed OK the IID said start engine, started engine and FBH failed with E7 fault, reset with IID, retried and loads of white smoke the FBH stopped, ever since then when starting the car FBH tries for 30 seconds and cuts out with the code posted above.Discovery 3 SE gone but not forgotten.
Discovery 4 HSE (Mrs S)
Discovery 3 GS project, great, but manual, Gone.
Discovery 4 XS
30th Dec 2020 11:02 am
Motolab
Member Since: 18 Oct 2019
Location: Sleen
Posts: 1820
you can test it with IID without the engine... just the FBH....
white smoke in a FBH diesel is unburnt diesel.... so there IS diesel...... if you can prime it, the dosingpump works... if you can hear it clicking it works...
or it is tooo WET inside (diesel) (too much prime) OR glowingplug/measuring plug faulty
it is cold, dieesl does not evaporate now..
fuelprime is only needed with a new fule line or new pump... (= empty fuel line) never with only a disconnected Heater unit...
i bet on: cleaning it again.. remove exessive fuel (deposits)
and do a test, full battery 12,6 V or more with battery loader attached still to your battery, with IID and FBH only without motor running... never shorter runs than 10 minutes, or the glowplug will get dirty / glazed and stopf functioning very soon...
why do i think i know this all? i had a business in FBH for 15 years... Webasto, eberspacher... air and water heaters incl TT-V and EVOBest regards
Harold
Always looking for Pre '55's & Pre war British Motorcycles! knowing or having one for sale? PM please. I visit the UK 6 times a year
Ps. I edit my texts quite often, english is not my native language, so I will edit My “typo’s” etc.
30th Dec 2020 3:16 pm
davecars
Member Since: 04 Feb 2012
Location: Scotland
Posts: 166
Thanks motolab
Please excuse my ignorance but how do you run the FBH without the engine running (in my defence I have only recently acquired a IID and still learning), I have ordered new seals and gasket ( incase I have damaged others when I rebuilt FBH ), is it best to connect to another vehicle that is running to guarantee the battery battery voltage, or would a battery charger suffice.
When I cleaned the FBH last I did not disturb the ceramic discs I only cleaned ( very throughly ) the combustion chamber, should that part have been disassembled ? again thanks to all who helped, I will follow up when I have cleaned and rebuilt FBH again.Discovery 3 SE gone but not forgotten.
Discovery 4 HSE (Mrs S)
Discovery 3 GS project, great, but manual, Gone.
Discovery 4 XS
30th Dec 2020 6:37 pm
davecars
Member Since: 04 Feb 2012
Location: Scotland
Posts: 166
Hi all
I now have a working FBH, removed the unit disassembled, on inspection found seals and gasket ok but fuel resadue inside the chamber, when I originally cleaned the chamber (first time around) I ,used a paraffin cleaner bath, (I wondered if this could have been detrimental), anyway cleaned with carburettor cleaner, left overnight, rebuilt, re-fitted and with a little persuasive help, it started and has continued to work for the last three mornings when well below zero degrees, keeping fingers crossed.Discovery 3 SE gone but not forgotten.
Discovery 4 HSE (Mrs S)
Discovery 3 GS project, great, but manual, Gone.
Discovery 4 XS
8th Jan 2021 2:21 pm
Motolab
Member Since: 18 Oct 2019
Location: Sleen
Posts: 1820
I made a Good bet Best regards
Harold
Always looking for Pre '55's & Pre war British Motorcycles! knowing or having one for sale? PM please. I visit the UK 6 times a year
Ps. I edit my texts quite often, english is not my native language, so I will edit My “typo’s” etc.
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