XUD wants to run 24/7............

[CitroXim]

Much obliged Jim, please advise condition of the solenoid Jim, so we can arrange something re mail or pickup.

Will do Ed, If I get a chance this evening I'll give it a check and will let you know soonest Where's Marshfield?

I'll be stripping the dead pump as I'm curious to know how and why it died. I'll report on that in due course...

Basically, they usually seize in the distributor head through lack of lubrication due to the veg being too thick to flow in the required areas due to the very fine clearances. This one has not seized in the distributor head as far as I can tell as the lift pump still works, hence my interest in what's died.

It was not SVO or WVO veg that killed this pump; it was bio diesel. The provenence of which I'm not sure. It may have been a dodgy batch of homebrew stuff.

[ed4ferrets]

Thanks Jim, I'm interested in the results too as I also use a small amount of filtered wvo per tankful of dinosiesel.

Marshfield is midway between Bristol and Chippenham on the A420.

[docchevron]

Lovely place it is too!

Bio diesel will kill a Lucas pump. Infact almost anyting will kill a Lucas pump, they are stupidly fragile.

Although people that believe a Bosch pump will run on anything are bloody stupid too. It make take longer to murder a bosch, but it'll still die.

If the lift pump still pumps I suspect you'll find loads of metal filings and swarf in the pump and the remains of a beaing and a well creamed governor...

I stripped a Lucas pump off a TUD from an AX owned by a mate a little while ago.
He'd been running it on Bio for a while. There was absolutley bugger all left of the innards of the pump, it had just imploded. Quite amusing for me, and expensive for him!

[CitroXim]

Ed, I'm so sorry I went and inspected the stop solenoid on the dead pump I have and found it to be gutless, literally The person whose car it came off, on my advice, removed the plunger to effectively disable the stop solenoid as a test and did not replace it so it's no good to man nor beast now. The solenoid bit is OK but I'll bet the problem with yours is the rubber tip on the end of the plunger is duff. So, my fault Ed, in a roundabout way, that I can't supply a replacement solenoid as promised. I really can only apologise, sorry

I popped the lid off the dead pump and had a quick look to see what had happened to it. I found it full of crud and rubbish and smelling very strongly of varnish (of the Ronseal variety). The bearings are wrecked and the fuel metering pin is seized solid in the stop position.

The contamination looks very much like the shite I found inside this Bosch pump I stripped a while back.



That pump cleaned up and survived but the Lucas is a write-off. Shows how much tougher the Bosch is...

I know this Lucas ran on bio and I'm assuming the bio stripped years of crap and varnish deposits off the tank walls, the filter plugged and the owner then ran it without a filter for a while as a "get you home". Else that, the car had been idle for a year or so with bio sitting in the pump and it turned to this nasty stuff through degeneration.

Any thoughts Doc?

[docchevron]

Ed, I cant do owt till Jan 5th given that my dudes have buggered off for xmas break, but I did give a Lucas pump to them for bits that had a solonoid (working) on it. I suspect they still have the remains of said pump, so I'll grab the solonoid, but again, I cant until Jan 5th, unless I break into the workshop, which I suspect would be unpopular....

Any thoughts Doc?

Yep, my immidiate thought is "that is fucked"....!

I suspect your theory that the bio sitting around in the pump killed it will be on the money mate.
Certainly I've not seen anyting like that on pumps I've stripped that have gone bang solely running on the veg / bio shite, but I have seen similar stuff on a 405 that had been running a mixture of SVO / straight veg oil / recycled veg oil etc that had been sat around for 6 months.
When we stripped the injectors down they were clogged solid with browny, tarry shit. Infact I'd have said they'd been smoking 100 L&B a day for 40 years!

It does rather reinforce what I've said for a longntime. There's a reason why diesel cars run on diesel. They're designed for it.
All this running diesel engines on any old shit, with or without a twin tank system, or fuel heaters will enevitably only lead to one outcome. The car will cease working.

I do agree though that the Bosch pump is just better in every conceivable way. You can get away with running it on shit for longer, but in the end the outcome is always the same.

IMHO there is only one engine that will run on anything that will burn for an indefinite amount of time, and thats a 10.45 litre Gardner engine.
That had the sexiest injection pump EVAH. Anything else is ust asking for trouble.

[ed4ferrets]

Any 10.45 litre Gardner engines lying around please Santa.... oh, and an industrial sized shoehorn please

[DavidRutherford]

Most Mercedes-Benz engines have a design which allows them to run on any-old-shit(TM), as the injection pump is lubricated by engine oil, and not the fuel it pumps. Essentially this is the killer (relying on fuel for lubrication) and is the reason most engines die. The engine itself is fine, the pump is less-so.

The engine from the W124 series is particularly well known for being able to inject anything you throw at it.

[docchevron]

any-old-shit(TM),

as the injection pump is lubricated by engine oil, and not the fuel it pumps. Essentially this is the killer (relying on fuel for lubrication) and is the reason most engines die. The engine itself is fine, the pump is less-so.

The engine from the W124 series is particularly well known for being able to inject anything you throw at it.

Ah ha! There's your answer then Ed, get an old Merc diesel engine, same idea as the Gardner pump, but more managable in size and weight!

[CitroXim]

I got to have a look at the Lucas pump that failed on my nephew's 205 today. Two things were achieved; I determined how to disassemble a Lucas pump and what went wrong in the dead pump.

The pump had allegedly failed whilst running on bio-diesel and had died slowy, finally refusing to rev from idle before dying completely.

Lifting the lid showed contamination very similar to the mucky brown stuff as seen in the Bosch pump above. The interior of the pump also smelt as if the decorators had just been in; it smelt of Dulux

The main problem that stopped the pump was that the fuel metering pin (attached to the end of the governor) had seized in the stop position and took a bit of shifting. Apart from being mucky and having slightly noisy bearings, the rest of the pump is OK and will clean up and live to pump diesel again.

I have reason to believe the car stood about for a long time (around a year) and the muck you see is the result of the diesel decomposing to something horrible during that period. The bio-diesel was a red herring.

As is well known, these pumps die very quickly if run on veg. The reason is the distributor rotor shown in the picture below seizes in its sleeve due to lack of lubrication. The clearances are very close and only thin diesel can get in there to lubricate. Thicker veg just cannot penetrate and as a consequence, the rotor heats and welds to the sleeve. You can, if you look carefully, just make out some scuffing on the rotor and this looks like the start of what happens when lubrication runs short. The small device on the right of the picture is the seized metering pin; the cause of all the problems in this pump.




And here is a picture of the pump all in bits on the bench...

[jonathan_dyane]

I'm impressed by your willingness to leap into the dark art of injector pumps, I have a Lucas pump on the shelf with failing bearings which I've been meaning to dismantle and see if I can do anything with for some time. No doubt it will stay there until I urgently need a pump and I will be hurridly trying to build one out of two...

[CitroXim]

I love my diesel pumps Jonathan In fact you might say I'm a bit of a dieselhead really

I also love forensics; If something has gone wrong I need to know exactly why. I need to know exactly how things work too.

Further investigation into the pump pictured above shows there is corrosion present, particularly on things that were originally plated steel, like the governor plate. The plating has significantly discoloured and the bearings are quite rusty, as are the unplated steel bits. Therefore, the contamination is of a different nature to that in the Bosch pump I spoke of earlier. In that one, the contamination cleaned off relatively easily to leave shiny metal, even on unplated steel; in the Lucas, there is real rust Good diesel will never do that as every other pump I've opened that have run on diesel have shone like new inside.

I have to conclude therefore that the bio-diesel was not such a red herring. It might have contained sufficient moisture to leave a considerable amount in the pump or perhaps it was not fully reacted and both meth and caustic soda got in and did the damage.

Makes one think twice about the wisdom of running on anything but diesel.

Bearings are a bit tricky to replace Jonathan. The Lucas is a bit tricky to pull to bits, a little harder than the Bosch, and a special tool is needed to extract the cam ring peg as shown in the picture below. It's generally very tight and hard to get purchase.



It's a circular shape with two flats ground on it and is very tight. You can pull the pump apart without removing the cam ring but you cannot get to the governor or the main bearings..

The picture shows some of the contamination still present in the pump body, especially evident in the region of the governor. That is rust

I'm trying to get hold of the required tool.

[mat_fenwick]

Interesting photos and story Jim! Do you think it's a possibility that (if water had got into the tank) that some of it could hae got past the fuel filter and into the pump, causing the rust?
The reason I thought of that is that our heating oil tank had developed a leak, and the boiler doesn't run quite so well on mayonaise... Had to drain about 60 litres of water from the tank and flush all the lines though.
Caught it in time before any rust started to form though.

[CitroXim]

All diesel (and by extension, heating oil, WVO and biodiesel) has entrained water Mat, and this settles over time at the bottom of the tank. Heating oil tanks normally have a drain cock at the lowest point expressly for draining accumulated water and it needs doing quite often.

The same happens in car diesel tanks and after a few years a good bit will accumulate but sadly nobody provides a drain cock. Any water in a car tank will soon mix in again with the diesel with motion and one of the main jobs of the fuel filter is to catch this entraiend water before it can start munching away at the pump. The older XUD filter designs that that comprise a big canister are far better water-catchers than the pathetic little thing on the thermostat housing used on later XUDs.

I reckon, on the pump in question, that either water got past the filter as it was the later type or, they ran it on bio which scoured the tank of old shite and varnish and plugged the filter as a result. If they removed the filter element as a "get me home" dodge, sufficient water and shite could well have got through to the pump to do all the damage. All conjecture on my part sadly...

It's a good policy to drain your filter housing regularly, replace your filter element regularly and NEVER run without a filter...

Modern diesel is much better than that of old with regard to entrained water and the need is no longer seen to fit a "water in diesel" warning lamp. In fact Citroen deleted them around 1996.

[mikesg]

Hi Ed
It must have been an easterly blow from Marshfield to Chippenham, cos ny TZD has caught the 24/7 non stop "virus" would you believe. It started on Saturday in the local car park with my lady Wife at the wheel. She switched off, removed the key, the engine reduced speed a little and kept running. I jokingly said you mst have used the wrong key dear. She told me not to be stupid. The engine stopped after a short time.
Having charged the battery overnight, started the engine 3 times & had to use the manual stop to shut down each time. So it would appear that the stop valve is up the creek. Btw, I only use diesel fuel.

[BX596]

Must be catching.See my previous post
http://www.bxclub.co.uk/forum/viewtopic.php?t=9489
I've run on 50% SVO for about 3 1/2 years,without any problems,apart from diesel pissing out from the spindle thingy.I'm sure Ken will know the technical term for it,he fixed my leaky pump after all