Bosch diesel pump

[lucida100]

Help!!!!!
I have a 2001 1.9 tdi, Boxer based, motorhome with 29000mls that we parked up last November, at that time running perfectly.
We came to use it 3 weeks ago only to find it smoking badly with a mis-fire on nos. 1 & 4. After checking glo plugs & replacing fuel filter we decided to fit new nozzle kits to the injectors, this cured no. 1 cylinder but not no 4. The fuel supply pressure to no.4 seems to be down (no leaks tho'), the injector is working fine.
After speaking to our local unhelpful diesel specialist, he suggested a fuel pump (Bosch) overhall at around £500 providing we took the pump to them. I think it is unlikely at 29000 but there you are.
Cash is a problem at the moment so I have looked at the possibility of fitting a second hand pump only to find that even tho' the pumps look the same the part nos. are all different. I am unable to find one with the same number as mine (0460494430 XUD212). Has anyone any idea how these pumps differ? Is it pressure, I am baffled.
Any help would be appreciated.

Lucida 100

[spider]

This is probably something for Jim really I guess.

As a stab in the dark so to speak, if its a 1.9 it should be an XUD or a DW8 in which case the nearest 306 / 406 / 206 as appropriate will provide a pump, although there are differences in the ages of these pumps as to their suitability. Don't go looking just yet, we need to determine a few things as the pumps on these (DW8 especially) need to be the correct type.

The "problem" I have reading your topic is you say 2001, so its got to be DW8 however they are going to be underpowered to fit into a large vehicle, the XUD stopped being fitted around 98/99 so I can only assume its a HDi unit, I doubt they fitted a DW8 to the Boxer . I'm not sure which HDi units they fitted either...

I think if you can clarify the engine type it will help loads or possibly a few pictures of the engine bay may help so we know what unit is actually fitted.

[CitroJim]

I think if you can clarify the engine type it will help loads or possibly a few pictures of the engine bay may help so we know what unit is actually fitted.

That will help enormously. However, having a Bosch chances are it's an XUD.

Fundamentally, the design of the pump means there's nothing internal that can really cause a misfire on one cylinder. The pumping element is common and all that is unique to any cylinder is the delivery valve which is accessible without dismantling the pump. It can be found on the end of the distributor head and is in fact what the delivery pipe screws onto.

It is possible, after a long lay-up and especially if it's been running on veg. that the delivery valve may be a bit gummed up. It can be removed but be careful as there's a big spring and a two-piece plunger behind it along with a copper washer. Put a clean rag under the pump body to catch any errant bits!

I'd also be suspecting the injector itself. Not too hard to swap them over as a test...

I don't believe you'll find the pump itself at fault.