Webasto wont start

[Lesd]

Our Webasto thermo top C ran out of fuel and since I refilled the tank it wont start up.

This has happened in the past occasionally and it usually sorts itself out if I restart it a few times but this time its being not playing ball !

 

I start it remotely from the timer panel and can hear it going through its start up phase, the fan runs, then slows a little and then slowly speeds up, I hear the fuel pump ticking and that speeds up too as it should but after a minute or two the fuel pump stops, the fan purges again and the whole process starts again, after the second attempt it stops dead.

 

I've tried to reset by pulling the fuse, no luck (Im not sure its locked out as it is trying to start after the test phase) There is white smoke coming from the exhaust when the fan speeds up but the odd thing is when I remove the fuel pipe I get some white smoke coming out of the fuel inlet, I also see a small amount of white smoke coming from the unit near the exhaust outlet but I can see exactly where its coming from. I dont think the exhaust of blocked as there is plenty of smoke coming out when its trying to start.

 

Im getting fuel dripping from the delivery pip per tick, batteries are topped up and I've tried starting the unit with the main engine running to make sure voltage isnt the issue.

 

Can anyone suggest any more basic checks I can make ? I dont want to strip the whole thing down if there are easier things to try first.

 

Thanks

Les

[bottle]

White smoke....unburnt fuel.

 

Heater plug? (I guess the Webasto has one)

 

 

This is total guesswork.

[STUBAG]

White smoke....unburnt fuel.

 

Heater plug? (I guess the Webasto has one)

 

 

This is total guesswork.

Almost certain to be coked up and in need of a quick strip-and clean. Can you find the thread on here by Chris W who very clearly showed how to do the job? If you are unable to do it yourself, there should be someone nearby who can help. It really is not too tricky, and when you've done it once, you'll never have cause to complain that Webastos are the "spawn of the Devil".

[OldGoat]

Our Webasto thermo top C ran out of fuel and since I refilled the tank it wont start up.

This has happened in the past occasionally and it usually sorts itself out if I restart it a few times but this time its being not playing ball !

 

I start it remotely from the timer panel and can hear it going through its start up phase, the fan runs, then slows a little and then slowly speeds up, I hear the fuel pump ticking and that speeds up too as it should but after a minute or two the fuel pump stops, the fan purges again and the whole process starts again, after the second attempt it stops dead.

 

I've tried to reset by pulling the fuse, no luck (Im not sure its locked out as it is trying to start after the test phase) There is white smoke coming from the exhaust when the fan speeds up but the odd thing is when I remove the fuel pipe I get some white smoke coming out of the fuel inlet, I also see a small amount of white smoke coming from the unit near the exhaust outlet but I can see exactly where its coming from. I dont think the exhaust of blocked as there is plenty of smoke coming out when its trying to start.

 

Im getting fuel dripping from the delivery pip per tick, batteries are topped up and I've tried starting the unit with the main engine running to make sure voltage isnt the issue.

 

Can anyone suggest any more basic checks I can make ? I dont want to strip the whole thing down if there are easier things to try first.

 

Thanks

Les

 

 

Shouldn't it be more of a spurt than a dribble? After all these units are pressure jet types. The pump delivers a small amount of fuel per tick - but it's at some pressure. I'm assuming (probably quite wrong) that you've used the 'basto releatively recently? If so then perhaps coking up is not so likely - unless of course it was struggling to fire even at that time. It took several times for my mikuni to start after I had disconnected its feed. You're supposed to wat for several minutes between startup attempts and power off as well.

[Timleech]

Shouldn't it be more of a spurt than a dribble? After all these units are pressure jet types. The pump delivers a small amount of fuel per tick - but it's at some pressure. I'm assuming (probably quite wrong) that you've used the 'basto releatively recently? If so then perhaps coking up is not so likely - unless of course it was struggling to fire even at that time. It took several times for my mikuni to start after I had disconnected its feed. You're supposed to wat for several minutes between startup attempts and power off as well.

 

I would definitely check the fuel filter.

I believe the Webastos have a separate filter, (some) Ebers have a tiny filter within the pump which can produce similar symptoms if choked.

 

Tim

[Guest]

Batteries OK?

 

If not try firing up with the engine running or while on shore power.

 

Not of course anything to do with the fuel supply but worth a shot as they are voltage fussy at start-up.

[STUBAG]

Batteries OK?

 

If not try firing up with the engine running or while on shore power.

 

Not of course anything to do with the fuel supply but worth a shot as they are voltage fussy at start-up.

See post #1

[nb Innisfree]

You say it ran out of fuel, is the new fuel the same? High sulphur fuel could be the cause.

Edited December 27, 2012 by nb Innisfree

[Lesd]

Thanks for the replies so far, just to add some info around the ideas you've raised;

 

1. I've only ever ran the unit on white diesel, we have a seperate tank for this heater, its 5 years old and never been a problem other than the odd hiccup after refuelling.

 

2. Im not aware of any filter in the fuel line, there's just the small webasto pump near the fuel tank.

 

3. Voltage is good and have tried restartin g with engine running.

 

4. I've held a big bag upwind of the exhaust when starting as it been windy and im told it wont like wind blowing up the exhaust.

 

5. I have Chris W's guide but dont want to strip it if there are simpler things to check first (cruiser stern install, bad rain currently not a great time for the first ever strip down by a novice!!)

 

6. Thinking about the fuel delivery, I guess it's more than drip but hardly a spurt lol

 

Ref the glow plug; if it was dead wouldn't the start up test not spot that and immediately shut the unit down ? I read somewhere it should measure somewhere between 0,25 and 0.75 Ohms (or there abouts), is there a simple way of measuring that without stripping it all down as per CW's process ?

 

Les

[Guest]

See post #1

 

No harm in trying though - it takes just seconds to do.

 

Plus we have no idea what the OP meant by 'topped up' in the absence of an accurate voltage reading it means nothing.

[STUBAG]

No harm in trying though - it takes just seconds to do.

 

Plus we have no idea what the OP meant by 'topped up' in the absence of an accurate voltage reading it means nothing.

Fairy Nuff....but the symptoms are, IMO, typical of a "clagged-up" burner/glow-pin. In fact I would bet a free service on it.Would like to know the outcome.

[Lesd]

For clarity, the batteries were at 12.65v this morning when I was attempting the tests, I also tried it twice with the engine running with the alternators delivering 14.4v. No luck with either.

 

Does anyone know how to access the glow plus to test it ? Can it be done without stripping the unit down ?

 

Les

[smileypete]

Sounds like a fuel or fuel delivery problem (blockage, contamination, air lock etc), though poss. it could do with a service too if that hasn't been done for a long while.

 

This thread might help:

 

http://www.canalworld.net/forums/index.php?showtopic=34507

 

Might be a small filter inside the pump fittings, ideally should be a decent size external one by the tank, maybe a separator too.

 

cheers, Pete.

~smpt~

[Stormbringer]

The glowpin plug is under the central black cover on the top of the heater.

If you remove the two always accessible plugs, and then the cover the glowpin plug is the one with the thick wires

(think its the centre most but can't be sure atm).

The only potential snag is the cover has a 'latch' both front and at the back of the cover,

However I have managed to remove mine without removing the heater. Just took a bit of jiggling and

I found swearing helped.too !!

The glowpin resistance should be about 0.3 ohms IIRC but ill check the manual and let you know.

I know all this as I have spent most of Christmas 'getting to know' my webasto intimately..lol.

Still not got mine running yet.

Hth Andy

[Timleech]

Sounds like a fuel or fuel delivery problem (blockage, contamination, air lock etc), though poss. it could do with a service too if that hasn't been done for a long while.

 

This thread might help:

 

http://www.canalworld.net/forums/index.php?showtopic=34507

 

Might be a small filter inside the pump fittings, ideally should be a decent size external one by the tank, maybe a separator too.

 

cheers, Pete.

~smpt~

 

It seems that current Webasto pumps don't include a gauze screen, or if they do it's inaccessible to the user.

Some (older?) pumps have ends which unscrew to reveal the screen, much like the Eberspacher pumps.

 

Tim

[Stormbringer]

Agree .. it does sound like a fuel problem. mine is (think burner inlet tube is blocked! )

Seems to perform a similar sequence as the op's

 

I have been finding bits of rubber stuck in all the fuel line connectors - suspect one of them is breaking down.

 

Andy

[MtB]

I start it remotely from the timer panel and can hear it going through its start up phase, the fan runs, then slows a little and then slowly speeds up, I hear the fuel pump ticking and that speeds up too as it should but after a minute or two the fuel pump stops, the fan purges again and the whole process starts again, after the second attempt it stops dead.

 

Mine does exactly this too when the batteriers are even a tiny bit low. I reckon you have a poor electrical connection that is preventing full battery voltage arriving at the webasto.

 

MtB

[Stormbringer]

Just stripped mine and fuel pipe into burner is blocked,as I thought....

For reference my pump was ticking much quieter than normal,

So much so that I had to feel it to see if it was running. Disconnected from the heater

the pump was noisier, pumping fuel happily into a container. I made up a lead with a microswitch

on it to fire the pump manually.

The pipe doesnt look like the

easiest thing to.clean either..any tips anyone ?

 

Interesting MtB . Thanks... I haven't checked the voltage.

Do you know what it needs to.see when under load by any chance ? Or do I just check

incoming voltage against battery voltage ?

Cheers

Andy.

[Justme]

Remember to check the voltage at the unit whilst it is actually starting up & using the glow plugs.

[Stormbringer]

 

 

Interesting MtB . Thanks... I haven't checked the voltage.

Do you know what it needs to.see when under load by any chance ? Or do I just check

incoming voltage against battery voltage ?

Cheers

Andy.

 

Ok..found the answer to that question so posted for others for future reference..

From the manual..

A low voltage level of 9.8 +/- 0.3 v (measured at the wiring harness input)

over a period of 20 seconds will cause an error lockout with a run down of 120 seconds.

 

HTH

Andy

[Stormbringer]

 

Ref the glow plug; if it was dead wouldn't the start up test not spot that and immediately shut the unit down ? I read somewhere it should measure somewhere between 0,25 and 0.75 Ohms (or there abouts), is there a simple way of measuring that without stripping it all down as per CW's process ?

 

Les

 

Hi Les

Ok..from the manual again,

Resistance at 24 deg C ...0.245 to 0.325 ohms with a test current of less than 5mA

 

Hope that helps mate..

Andy

[Lesd]

Thanks for all the comments, looks like I need to strip it down a bit to test voltage, glow plug resistance etc and then clean out all the burner etc... I've just read Chris W's 'manual' on how to do that so its a job for next week (need to buy some of the gasket sealant, torkx driver etc)

 

Andy, thanks for all the specific info you've dug out, hope you get your going ok.

 

Les

[Stormbringer]

Thanks for all the comments, looks like I need to strip it down a bit to test voltage, glow plug resistance etc and then clean out all the burner etc... I've just read Chris W's 'manual' on how to do that so its a job for next week (need to buy some of the gasket sealant, torkx driver etc)

 

Andy, thanks for all the specific info you've dug out, hope you get your going ok.

 

Les

 

Les, glad I could help

The strip and clean is fairly straight forwamrd and Chris W's instructions are brilliant.

But, be warned, the glowpin appears to be quite fragile!

Don't ask me how i know this......

Not sure what I did but the resistance has gone from 0.3 to 0.5 during my last rebuild...

On a brighter note I did get the fuel inlet line clear, just need a new glowpin now.

 

I suspect kings lock boatyard will be my nearest supplier, unless anybody knows anywhere better in Cheshire ?

 

Cheers

Andy

[lynalldisocvery]

Im not sure on the diesel thermotop, but when i wanted a pin for my petrol one it only came with the burner cartridge

 

 

Lynall

[Stormbringer]

Im not sure on the diesel thermotop, but when i wanted a pin for my petrol one it only came with the burner cartridge

 

 

Lynall

 

 

Thanks Lynall, I fear that you are correct . I have only found complete burners during my search.

Looks like I wasted a few hours unlocking the burner fuel tube then

Cheers for the heads up though..

 

Andy