Diesel leak at output end of pump

[Diplomat]

I've got the fuel leak with a difference!

Close inspection after cleaning has revealed that my injector pump is leaking, presumably around a seal, from the part described as the 'Hydraulic Head'.

This is the part of the pump nearest to the rear of the engine. Here is an image of a similar pump linked from a VW forum:
http://bricofoy.free.fr/voiture/pompe/dsc05411.jpg

Located centrally between the four pipes to the injectors is round cover with a bolt through its centre, persumably holding it in place. Fuel weeps from beneath this cover when the engine is runnning and drips from the nearest corner of the housing. Nothing is dripping from the other two covers on either side of the pump.

Needless to say I haven't removed the cover without consulting the forum experts. I dont want a spring to leap out propelling small parts in front of it!

So far I have only loosened the bolt which caused more spillage from its hole. The cover remained fast. Not sure if it just needs a slight tap to free it or if it is threaded.

I guess that there is an 'O' ring under the cover, although it almost looks as though there is a fibre washer where the weep is. If so, does anyone know if it is the same size as the others which are the usual ones which leak?

Has anyone else dealt with a leak in this end of the pump?


Thanks

Frank

[mikexgough]

Parts list for Diesel Pump......Zexel/Bosch numbers

Diesel Pump exploded diagram

Hope it helps......

[roofraisers]

The centre bolt is a fuel bleeding point & should have a washer under it.You shouldn't have any issues removing that one & inspecting that washer & replacing it if necessary.
The larger bolt that the small centre one threads into should also unscrew, BUT I'm not sure what is behind that one.(In the bouncy small spring & other high speed propelling pieces department).I would have thought there will be an O ring of some sort to provide the seal.

I would remove, clean & inspect the small centre bolt & replace & then re-test before delving into the next stage.

Hopefully some one may give a bit more info.

Nigel.

In the time I've been typing this, Mike has put some diagrams up.... well done!

[Diplomat]

Certainly does help, Mike.

That is the first exploded diagram that shows it clearly when magnified. Others I have looked at just blur!

The parts concerned are 130, 130/3 and 130/4 which certainly looks as though it could be a fibre washer rather than an 'O' ring.

The part which I call a 'cover', for lack of a better name. certainly looks like it screws into place, which would explain the flats on it and why it didn't come away with the bolt loosened. In which case there is quite likely a fibre washer instead of an 'O' ring.

I'm just a bit worried about undoing it. Not sure why it needs the bolt in the end though?* Belt and braces perhaps or does it do something more important that I will cock up by undoing it?

All I have to do is ally it wth the parts list.


*Just read your reply, Nigel. Many thanks, that explains. I don't recall a leak at the bolt, but it would be great if all it needed was a new washer there.
Luckily there is a Bosch specialist very locally. With luck I might speak to a knowledgeable person there tomorrow.

Frank

[Diplomat]

Now that the bolt has been identified as a bleed screw, I wonder if I will need to leave it undone until fuel comes out should I have to remove and replace what I now know is called the 'capsule' ?

Frank

[wonkanoby]

as they self bleed after running out i would say no

[rita]

Hi,this might help..

http://www.igmaynard.co.uk/bongo/forum/ ... et#p299810

Cheers..

[Diplomat]

That's very useful,Rita. Thanks. Will ask about a tool when I go to Bosch dealer today.


Frank

[rita]

That's very useful,Rita. Thanks. Will ask about a tool when I go to Bosch dealer today.


Frank

Hi,it would be worth also checking the distributor body seal 51 on the diagram,these have a habit of leaking (especially if cooking oil has been used) you will see drips from the bottom r/h set screw 60 in the diagram.

Cheers

[Diplomat]

Ohhh....

That's exactly where the drips are coming from.

Replacing that seal (51) looks like a 'pump off' job.

This doesn't look like good news!

[rita]

Hi Frank,

How did you get on with your Diesel leak at the pump??

[Diplomat]

Hi Rita.

The pump problem is on the back burner, I've just done the exhaust and finished the nearside front shock today.

It's definitely the back end of the pump where the oil is coming out. May well be from the seal (51) you suggested.

However, there are signs of weeping around the seal under the 'capsule' so am dealing with that when I can get hold of the correct socket. Meanwhile I'm looking at tightening the bleed bolt to see if that tightens the capsule with it.

My mark 3 drip catcher is now in place and touch wood none is going anywhere except into a collection bottle lower down. It's sudeenly a lot cleaner underneath and not frying on the hot engine any more.

If it's got to come off then I need to find someone who knows the pump and how to put it back on correctly. I've read too many stories of not starting again. The local Bosch guy gave me a few suggestions so may go back to him in due course.

What I need is a Bongo Guru in the area but we are not too lucky in that respect. You'd think that statistically there would be more Bongos in London than anywhere else!


Frank