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Could I have misaligned Diesel Pump internals?

Posted: 06 Sep 2016, 15:22
by Dantes
Had leaking seals on my JX 1.6TD pump, so I replaced all the other seals at the time all in situ. Having issues now priming the system now and wondering if I might have mucked something up in the pumping order (at the high pressure distribution end)? have tried to bleed & prime, but maybe insufficiently.

When at Top Dead Centre on the flywheel mark, which nozzle is next to 'inject'? piston 1, right?

Is it normal that when I add diesel to the pump via the fuel in-line, that the diesel line empties (into the pump) if not connected to the diesel filter?

Lastly, I have a constant 5cm bubble in the diesel fuel line (sits in the middle of the line in at rest), no matter how I try to get rid of it, it returns like a bad penny. Is this 'normal'?

Thanks in advance. Ta.

Re: Could I have misaligned Diesel Pump internals?

Posted: 06 Sep 2016, 16:21
by dave friday
What seals did you replace? did you remove the cam belt or alter the cam belt setting? when I refitted my pump I filled the pump up [until I couldn't get any more Diesel in]

Re: Could I have misaligned Diesel Pump internals?

Posted: 06 Sep 2016, 16:29
by Dantes
Cheers Dave for the reply. No, the one thing I wanted to avoid was playing with the belts (will do that job when I know everything is ticketyboo).

Replaced the seal between the low to high pressure elements of the pump, and those at the distribution end (and the annoying one under the pump for the 'choke' cold start). Its been about 3 months since I did it, so now with it not starting I'm wondering if there is an exact sequence within the chamber that I may have rotated without thinking to mess up the order relating to the piston intake.

Everything seemed in order when I rebuilt it, just niggling doubts that my inexperience with diesels is showing through. Its either that or my patience is not what it once was, and this priming malarkey has me nervous.

Re: Could I have misaligned Diesel Pump internals?

Posted: 06 Sep 2016, 17:03
by dave friday
did it run after you replaced the seals?

Re: Could I have misaligned Diesel Pump internals?

Posted: 06 Sep 2016, 17:48
by Oldiebut goodie
I have a copy of a web page on rebuilding a ve pump, if you want a copy to peruse pm me your email address. It may help with seeing if you did it correctly or not. Just checked his webpage and it has returned http://gnarlodious.com/vanagon/Bosch_Pump/-Rebuild (it went awol once)

Re: Could I have misaligned Diesel Pump internals?

Posted: 06 Sep 2016, 18:18
by multisi
Pump needs to be spun quickly to get it going,i tried cranking for ages then a mechanic helped me by spraying brake cleaner into intake while i turned the key.I had that same bubble in the tube before we got it spinning properly.

Re: Could I have misaligned Diesel Pump internals?

Posted: 06 Sep 2016, 19:16
by Dantes
As ever Oldiebutgoodie you are a star :D ; You should change your name to OldFaithful as you are so reliable on this site. I'd buy you a real ale if I wasn't in Catalonia. Someday maybe.

From the link I may well have positioned the rebuild with the plunger shaft 180 degrees off (part5 of the link).

Is there any way of being sure as I keep thinking I'm only a recharged battery short of it firing up?

The old girl could do with some professional service, but I love working through the problem (but also miss driving her).
Thanks, any suggestions welcome. And thanks Multisi, though I've never heard of using brake cleaner in the fuel line (guess its just a little solvent action).

Re: Could I have misaligned Diesel Pump internals?

Posted: 06 Sep 2016, 21:51
by Timburrows
When flywheel is at TDC then number 3 piston should have just had fuel injected in and wiling be on the power stroke if I remember correctly