Maverik Posted November 15, 2011 Share Posted November 15, 2011 Ok, the history is here :- http://forums.lr4x4.com/index.php?showtopic=72215&hl=&fromsearch=1 Summary, 2nd hand webasto burner installation not working. I've tried everything I can think of to fault find this problem and I can't work it out, I'm at my wits end. Does anyone know an expert I can ring/contact with regard to these burners? I don't know what else to do... A rather defeated Mav Quote Link to comment Share on other sites More sharing options...
poohbear Posted November 15, 2011 Share Posted November 15, 2011 Hi Mav, Would have thought it unlikely for two units to fail in the same way in one installation. If it's electrical - is the supply cable upto the job, if it's not large enough the volt drop across it may be causing your problems, likewise if your ground is no good. Otherwise my money is on fuel delivery, or lack of it. Have you checked the pump will deliver enough fuel given the height of the heater above the fuel tank, any blockages/kinks in the lines? It could be that when the engine runs it will pressurise the system enough to give you 2 minutes of burn. In any case - don't give up! The solution is probably very simple and not far away! Dave. Quote Link to comment Share on other sites More sharing options...
reb78 Posted November 15, 2011 Share Posted November 15, 2011 Its not locked out or something like that is it?? I know that the eberspachers give you ten (or is it five) tries to start and if unsuccessful they lock you out - something to do with the fact that it pumps fuel through at each start up attempt, so eventually locks out to stop it blowing up??) They might need re-setting by a service agent. Just a thought. If it seems to burn at all, then i guess it cant be the above - are you getting any flame at all? Quote Link to comment Share on other sites More sharing options...
Maverik Posted November 15, 2011 Author Share Posted November 15, 2011 Hey Reb, you can re-set the lock out just by disconnecting the power for 10 seconds I think it is, but good call. I don't think there is a flame no, tested the glow pin this evening and thats fine, glows white hot. Dave's got me thinking the only time it has actually worked was when I had the duff one way valve that didn't work, hence I managed to get the thing working when the engine was on, I put a new one way valve in and if I recal I don't think I've had it running properly since... I'll have to try and fire it up again and see what the fuel is doing, but I don;t think its that as the thing blows out huge amounts of vapourised diesel when it evidently doesn't light, which suggests to me the fuel is ok. Its like the glow pin goes out too early or something. I wonder if that one was valve is screwing with the fuel supply to the pump, hmm will have to check the fuel lines to make sure there isn;t any obstructions, its certainly not sucking air. but I really can;t see it being a fuel feed problem... So i did get a flame with the first unit, but then it stopped working, but then replaced with new unit, which I haven't got lit at all... Quote Link to comment Share on other sites More sharing options...
digger 2 Posted November 15, 2011 Share Posted November 15, 2011 have you looked on the rover 75 & zt owners forum there's a guy called keith seems to know a lot about these heaters. found a lot of usefull info on there when fitting mine. also have you tried running it in a separte fuel supply ie a pipe in to a gallon can of diesel then straight to the pump might be worth a try. Quote Link to comment Share on other sites More sharing options...
Maverik Posted November 15, 2011 Author Share Posted November 15, 2011 Cheers digger, will drop him a line. Going back over what I've done it, the only thing i had changed/thought i had fixed was the fuel, there is flow but maybe it is restricted somewhere, i'll pull off the pump supply and feed it of a jerry can and see what happens.... after I've put the burner back in... I'm not proud to say it but I've got it down to 40 minuets to totally remove and strip a thermotop c from my truck... this better be worth it if it ever starts working! Quote Link to comment Share on other sites More sharing options...
reb78 Posted November 15, 2011 Share Posted November 15, 2011 this better be worth it if it ever starts working! Oh, it will be! My eberspacher is great! Perhaps try putting the 'dodgy' valve back in, or missing it out completely. What you said above suggests it could be the replacement valve perhaps. Didnt know that about re-setting the lock-out. I dont think its that easy for the eberspachers? Quote Link to comment Share on other sites More sharing options...
poohbear Posted November 16, 2011 Share Posted November 16, 2011 'hard reset' - on my Webasto is pull fuse 1, but that is with original Webasto loom which has three fuses. I think fuse one is just for the 'brain' as it is only 1A. I reckon running from a jerry can is your next test. Failing that have you thought about a bench test - if you can set up a test rig you can check individual components in the comfort of your garage/workshop/kitchen. Bit of a ball ache mind you! Quote Link to comment Share on other sites More sharing options...
Maverik Posted November 16, 2011 Author Share Posted November 16, 2011 'hard reset' - on my Webasto is pull fuse 1, but that is with original Webasto loom which has three fuses. I think fuse one is just for the 'brain' as it is only 1A. I reckon running from a jerry can is your next test. Failing that have you thought about a bench test - if you can set up a test rig you can check individual components in the comfort of your garage/workshop/kitchen. Bit of a ball ache mind you! I did some testing yesterday in which I dissasembled the unit then went and plugged it all in (in bits) and started it up, I know the individual parts start working like glow pin fan, water pump etc. As regards a bench test, that is a pain as it would mean pulling the loom out which is a last resort for me really... but yes I'm not far off!!!... I'll be having another look at it this evening. Quote Link to comment Share on other sites More sharing options...
MattH Posted November 16, 2011 Share Posted November 16, 2011 What is the internal diameter of the fuel supply pipe? When I installed my webasto I "borrowed" some pipe from work that I thought would do the trick. It primed up eventually but never seemed to get to full burn. I replaced the whole run of pipe with some other pipe and hey presto. On my webasto I have an LED in the cab that is linked to the pump so I can see the rate it is pumping at, your two minutes fits in with the maximum rate of pumping ie it has gone through the preheat and is going into full power, generally points to fuel starvation. It will pump out diesel fume when it shuts down, its unburnt fuel that is making its way through. mine does the same when you turn off the engine during a full power burn cycle. On mine (Disco2) the pump is at the rear with a dip tube into the tank and no return. Cant remember the diameters of the pipes I used but can have a measure tonight if required. Would agree that easiest check would be pull the pump and using some short pipes run it from a jerry can or other container to prove it does actually work on full burn. hope that helps Quote Link to comment Share on other sites More sharing options...
poohbear Posted November 16, 2011 Share Posted November 16, 2011 Webasto installation manual specifys 2mm ID fuel line. Dave. Quote Link to comment Share on other sites More sharing options...
FridgeFreezer Posted November 16, 2011 Share Posted November 16, 2011 Fuel line ID is not that critical, air leaks / dodgy 1-way valves will be. I'd be tempted to remove it, put it on the bench and attach the bare minimum to make it run, and start from there. No point shoving it onto a vehicle, with various wiring, plumbing and fitting issues to worry about. Quote Link to comment Share on other sites More sharing options...
Maverik Posted November 16, 2011 Author Share Posted November 16, 2011 Ok, made some progress of sorts... took the fuel line off above the 1 way valve put it in a tank and fired it up, worked fine, ran for 20 min on its own all great... Ok, my burner and electric work. I bought 2 one way valves so I got the other one put it on the end and started it up. - worked just fine.... Put new 1 way valve in system started it up - worked fine except the valve was leaking fuel... "nipped" it up... and the thing popped as the threads on the rubbish alu body gave way and then the fuel really gushed out...! Conclusions: somehow it doesn;t like takeing fuel from the main lift pump feed, or a dodgy one way valve... As I've already cut the main fuel feed I want to try and pursue this feed method, does anyone know of a good quality, preferably branded fuel one non return valve??? Failing this, I'll have to look into a spill return line source which means tampering with the tank which I would like to avoid if possible... thanks for you help guys if anything it got me thinking again. Mav Quote Link to comment Share on other sites More sharing options...
poohbear Posted November 16, 2011 Share Posted November 16, 2011 My first NRV was a cheapy off e-bay, I think I damaged this by having a play with it (I blew through it to see what happened and think I popped it!). When I installed this and primed the fuel lines I could see the fuel draining back through the filter. The second valve was purchased from a diesel specialist - cost over twice as much, and you guessed it, looked identical to the e-bay cheap special. Fitted it (without messing around with it first this time!) and the system has worked perfectly since. I've also split the vehicle fuel feed just above where is comes up off the chassis rail and before it reaches the lift pump - I've gone: 8mm equal tee in fuel line to NRV then to fuel filter in 8mm comes out of the filter in 5mm and joins into the 2mm Webasto plastic line to the heater. Dave. Edit: Just re-read the manual - when using a dosing (I believe also called a metering pump) it has specific instructions for how it must be mounted. also taken from manual: Fuel Installation for Thermo Top S Fuel Supply In the case of carburettor or injection engines equipped with return lines, the heater's fuel system is to be integrated in the return line as shown in fig7. I'll try and scan the manual in tomorrow at work and get it on line. Quote Link to comment Share on other sites More sharing options...
Maverik Posted November 16, 2011 Author Share Posted November 16, 2011 My first NRV was a cheapy off e-bay, I think I damaged this by having a play with it (I blew through it to see what happened and think I popped it!). When I installed this and primed the fuel lines I could see the fuel draining back through the filter. The second valve was purchased from a diesel specialist - cost over twice as much, and you guessed it, looked identical to the e-bay cheap special. Fitted it (without messing around with it first this time!) and the system has worked perfectly since. I've also split the vehicle fuel feed just above where is comes up off the chassis rail and before it reaches the lift pump - I've gone: 8mm equal tee in fuel line to NRV then to fuel filter in 8mm comes out of the filter in 5mm and joins into the 2mm Webasto plastic line to the heater. Dave. Dave, Do you have a contact etc. for where you got the "working" valve from, I can;t belive there is nothing of any quality out there. Quote Link to comment Share on other sites More sharing options...
poohbear Posted November 16, 2011 Share Posted November 16, 2011 Bought over the counter here: Northampton Diesel And Electrical Services Ltd 25-29 Gambrel Road Westgate Industrial Estate, Northampton NN5 5DG Tel: 01604 755321 Have you read my edit above re. fuel metering pump - I'll try and get the manual uploaded tomorrow. Dave. Quote Link to comment Share on other sites More sharing options...
Maverik Posted November 17, 2011 Author Share Posted November 17, 2011 Cheers Dave. After sleeping on the issue, i remembered I found something else out last night. As i wanted to bleed the water system, I started the engine up when I had got the fuel pipe disconnected from the non return, being an innocent engineer I assumed that tapping into the fuel line before the lift pump, all that line would "see" was a suction. Well when I started the engine up fuel started to cascade out the non return valve... net effect, fuel was not been sucked down the line i was expecting it to be sucked down... so now i'm thinking, why do i need non return valve... A wee duagram to illustrate what i just said. Quote Link to comment Share on other sites More sharing options...
reb78 Posted November 17, 2011 Share Posted November 17, 2011 I wonder if tapping into the fuel lines is a problem (others do it, so i guess it shouldnt be). You can get pickups that fit into the filler pipe just before the tank. One of these would save the need to tap into the engine fuel supply lines. I looked last night but couldnt find a link though. I'll have another search later. Alternativley, my 110 tank has a spare port at the front that i think is for a breather (not needed) - if yours had something similar, you could put a pickup in there and seal it using a combination of hoses. Quote Link to comment Share on other sites More sharing options...
poohbear Posted November 17, 2011 Share Posted November 17, 2011 I noticed a similar thing - I can see the fuel level 'pulsing' in the filter bowl in time with the lift pump. In my case the thermotop has a flow and return connection, without the nrv I could see the fuel flowing back out of the lines when the engine and heater were off - so in my particular instance it stops the fuel draining back to the tank overnight. Interestingly, from recollection, the installation manual doesn't mention non return valves. D. Quote Link to comment Share on other sites More sharing options...
simonb Posted November 17, 2011 Share Posted November 17, 2011 On my 300Tdi, I took the fuel supply for the pump by T-ing into the fuel return pipe from the engine right next to the tank. Where have you got the Wabasto fuel pump? These pumps don't have much suck but lots of blow so you are better off having the pump mounted low down and close to the fuel tank. Pic of my set up. No non return valves used and fuel has never run back out of the Wabasto. Quote Link to comment Share on other sites More sharing options...
digger 2 Posted November 17, 2011 Share Posted November 17, 2011 on my 300 tdi i removed the tank sender unit drilled a small hole to fit a length of brake down then used a male and female with flares and a nut to make a fuel pick up pipe. not quite as long as the engine one so heater will run out first . it was cheap and fairly easy and it worked ok Quote Link to comment Share on other sites More sharing options...
poohbear Posted November 17, 2011 Share Posted November 17, 2011 Hi Mav, If I'm not being too dim the installation manual for Thermotop and Thermotop S should be attached. I would concur that the pump prefers to 'blow' rather than 'suck'. Dave. Dang it - file is to big to attach to post, I can PM it if your interested? Quote Link to comment Share on other sites More sharing options...
Maverik Posted November 17, 2011 Author Share Posted November 17, 2011 Hi Mav, If I'm not being too dim the installation manual for Thermotop and Thermotop S should be attached. I would concur that the pump prefers to 'blow' rather than 'suck'. Dave. Dang it - file is to big to attach to post, I can PM it if your interested? Hmm, I like the idea of the drilling out the sender option. Cheers Dave for the offer, I've got the installation, parts and service manuals already. I'll have to double check but I belive my pump is installed to the specification, so it should work. going to try mine without a non return and see what happens. Quote Link to comment Share on other sites More sharing options...
Guest Posted November 17, 2011 Share Posted November 17, 2011 Mav, A mate of mine has one of these, he has a coupling just before the fuel tank in the filler pipe, as mentioned above. if it's in the normal fuel circuit how do you get it to work in pre-heat mode? I was looking at this the other day as I think I have just found a Thermotop so will be going down this route very soon. Jason. Quote Link to comment Share on other sites More sharing options...
Maverik Posted November 18, 2011 Author Share Posted November 18, 2011 Right chaps... it works!!!! taken the non return valve out totally and fired it up, worked just fine. Switched it off, started up the truck, drove it around for 15 minuets, got back put the webasto on and hey presto worked again, a few air bubbles passed down the fuel line, but nothing to worry about, due to it being an "evaporater" type burner (i finally read the manual cover to cover) the gause type burner feed acts as a wee resovoir type thing so as long as you get the regular volume it can sustain itself. I wont be fully convinced its worked until its past this last test... which is leaving it for a couple of days, to see if any of the lines drain down. I can't see this being a problem as the fuel pump acts as a fuel cut off too, so when shut down it shouldn't leak etc. so as long as all the other joints are air tight, there is no reason the lines should drain down. I feel I've already proved that the engine doesn't suck the lines clear, so we'll see on Sunday night as to whether she starts on the button or wether they'll be any cranking going on... Big thank to Dave for giving me a push back on track to sorting it out... I was close to ripping the thing out and throwing it into the field! Quote Link to comment Share on other sites More sharing options...
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