Another intermittent fuel problem

[ColinJH]

I have a 2.5 Turbo Diesel, and like another of the members am experiencing problems with the van when it gets very hot - idling in traffic for example, when after a while the engine starts to run very lumpily after which its generally cuts out. After a short while it is possible to restart but with difficulty and normally with a lot of protestation from the engine - loads of vibration and shuddering which then clears. The cooling system has been fully checked by my local garage and coolant replaced - all fans have been checked and are working satisfactorily, but this problem keeps re-occuring either at the end of a long run, or as I already said when in traffic (not ideal!). My local garage has also now bypassed the fuel tank to ensure that its not a matter of any contamination in the fuel tank / lines, but this has not improved anything - the fuel filter has now been replaced twice, but again no real improvement. I am now being advised to visit a diesel specialis as the problem is suspected to be either injector or fuel pump related, but before doing so I thought it worth checking whether anyone has had experience of this problem also and whether there are any other ideas. Thanks

[321Away]

remove the fuel feed pipe and fit a piece of clear pipe which you can hold up in the air (gravity feed)fill it with diesel and fire up the carlet it run for a few seconds so you can see the fuel level in the pipe begin to drop, then turn the car off, if the fuel in the pipe shoots back up or fills with bubbles, your fuel pump seal is leaking. Alternatively replace the return pipe with a piece of clear and with the car running then switched off, look for bubbles.
Julian

[Northern Bongolow]

have you checked/cleaned out the bonjo filter in the inlet line in the pump.

[GOMEZ]

There is a post from the knowledgable owner of the bongo garage ex kelty/now kirkaldy who explains that the harsh winter we just encountered has resulted in a sharp increase in fuel pump failures in a lot of jap import cars, not just bongos.He has seen this first hand, the diesel specialist he uses has confirmed this and the diesel specialist I used to get mine fixed also stated that this is the case.I might be wrong, but there seems to be a reluctance among posters to recommend taking bongo's to diesel specialists for a full diagnosis on faults.By all means try the obvious (fuel caps, filters etc) but once you've exhausted these and the problem is still there, surely it's time for an expert to take over? It is costly, but flaffin about with outer seal replacements when you've no idea how the pump is seems like false economy to me.And just for clarity, i don't own/work for a diesel injection specialist company, i've just experienced the pain of having the stalling problem and going round and round in circles trying to fix it. I would recommend getting the pump looked at properly as soon as the simple fixes haven't worked

[The Great Pretender]

It is always worth checking the banjo filter, or throwing the bloody thing out..........IMHO...........
It can add to the strain on the seal that 321Away's post relates to.
I think that seal is possibly the culprit too.
You need to understand that the front part of the IP is a suction pump drawing fuel from the tank. If when hot the seal sucks in air and gradually less fuel as the temp rises until cutting out. It could also be air drawn in from before the IP.
A cheap solution to negative pressure problems is to fit a low pressure pump in the fuel feed to the IP. £25 to £30 should provide a solution or at least conformation of where the problem is.

[TonyBee]

Something like this?
http://www.thornycroftparts.co.uk/Elect ... 22922.aspx

I see someone with a bongo has fitted one and reviewed it.
I have just ordered one even though I currently have no fuel problems.

Tony

[missfixit70]

Be very aware of the cautionary note from Julian at the end of this thread
http://www.igmaynard.co.uk/bongo/forum/ ... mp#p496771

If your front seal has gone in your fuel pump, putting an electric pump in line will force diesel past he seal and into your sump!! so make sure you keep a close eye on sump levels.

Try replacing the fuel return pipe with a clear pipe and check to see if you have bubbles in the fuel, if so its your front seal.
Julian

[The Great Pretender]

Be very aware of the cautionary note from Julian at the end of this thread
http://www.igmaynard.co.uk/bongo/forum/ ... mp#p496771

If your front seal has gone in your fuel pump, putting an electric pump in line will force diesel past he seal and into your sump!! so make sure you keep a close eye on sump levels.

Try replacing the fuel return pipe with a clear pipe and check to see if you have bubbles in the fuel, if so its your front seal.
Julian

Hiya Kirsty.
The front seal is for the shaft that the timing sprocket fits onto so if any diesel was to leak past it would end up behind the timing cover wouldn't it?

[mikeonb4c]

Be very aware of the cautionary note from Julian at the end of this thread
http://www.igmaynard.co.uk/bongo/forum/ ... mp#p496771

If your front seal has gone in your fuel pump, putting an electric pump in line will force diesel past he seal and into your sump!! so make sure you keep a close eye on sump levels.

Try replacing the fuel return pipe with a clear pipe and check to see if you have bubbles in the fuel, if so its your front seal.
Julian

Hiya Kirsty.
The front seal is for the shaft that the timing sprocket fits onto so if any diesel was to leak past it would end up behind the timing cover wouldn't it?

Intriguing - guess we'll have to ask the source (Julian)?

[321Away]

If the seal has gone and the system is pressurised with an electric pump it forces the fuel out of the front of the pump and then runs back and down and under the cone part of the pump,and you may seem some in the timing cover but most of it ends up in the sump, where the drive gear (woodruff key) locates,as it passes through the gear and out the front of the block to lower cambelt pulley.

If a pump has a leaking seal, when you pull it,you'll see the residue of the leak, always a good indicator and a fast way to spot the problem.

Julian

[ColinJH]

All, thank you for your support and suggestions, this really has been helpful to me. I have decided that I must now refer the vehicle to a diesel specialist as all standard tests have been completed and have proven inconclusive. I will update this post when the cause of the problem has been diagnosed and fixed in order that anyone experiencing similar problems will have a reference. Again my thanks for the suggestions, it is really great to belong to such a helpful community.
Best regards,
Colin

[The Great Pretender]

If the seal has gone and the system is pressurised with an electric pump it forces the fuel out of the front of the pump and then runs back and down and under the cone part of the pump,and you may seem some in the timing cover but most of it ends up in the sump, where the drive gear (woodruff key) locates,as it passes through the gear and out the front of the block to lower cambelt pulley.

If a pump has a leaking seal, when you pull it,you'll see the residue of the leak, always a good indicator and a fast way to spot the problem.

Julian

Hi Julian, I'm struggling to understand your post.
Is this something you have had happen?
Are you saying the keyway on the crankshaft passes through the oil seal?
If liquid can enter the sump surely pressurised oil vapour can find its way back and contaminate the cam belt?

The only woodruff key I can find is this one on the IP but I haven't stripped a Bongo engine yet.......