lucas to bosch diesel pump problems...

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themildbunch
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lucas to bosch diesel pump problems...

Post by themildbunch » Fri Mar 27, 2015 7:17 pm

Took some time off this week to replace my very leaky Lucas pump on my TD estate.. finished the job but now even fully advanced I have trouble cold starting and lots of white smoke until the engine's warm... after that it runs pretty well and is quite powerful... somethings not right - I thought fully advanced the engine should be really knocking badly..

This is what I did:

I have a Bosch pump from a xantia with Bosch injectors and the correct fuel lines..
I even had the pump and injectors tested locally so these should all be fine.

1. Locked the crank, cam and pump in the correct position
2. I removed very soaked old cambelt and replaced the crank and cam seals while I was there..
3. Removed pump bracket and swapped pump mounting studs to Bosch position
4. Removed Lucas injectors and fitted cleaned Bosch ones with new fireseals and copper washers
5. Fitted Bosch pump with sprocket and locked it with timing pins.
6. Fitted new cambelt, set tension and rotated the engine twice and checked that it was still timed correctly, which it was...

7. Refitted everything else and put pump roughly in the centre of the slots for timing..

Very rough and (white) smoke -
If I advanced it to the max slot it ran at a high idle but still lots of white smoke until warm..
Went on a run and seemed fine but after cooling down - having the same starting issue...]

I don't think I could have got the belt out as the timing pins all lined up correctly -

Are the pump brackets for the XUD all the same?

Feeling very frustrated now!
1988 BX 19 Gti 16v
1991 BX 17 TZD Estate
1991 BX 17 TZD Estate

sdelasal
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Re: lucas to bosch diesel pump problems...

Post by sdelasal » Fri Mar 27, 2015 10:13 pm

I remember once having problems due to the fact that I had timed the pump with the cold start lever in the wrong position - i can't remember the details but in my case the lever altered timing and the mis-timing resulted in excessive smoke. That vehicle had a cold start cable - I know pumps are different but maybe worth checking that you timed the engine with any cold start device in the 'warm position'.

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themildbunch
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Re: lucas to bosch diesel pump problems...

Post by themildbunch » Fri Mar 27, 2015 10:37 pm

Thanks - never thought of that.. One these Bosch VE pumps there is a cold start advance solenoid thing that would have had a cable from the thermostat and gives a little more advance when the engine's cold.. The revs are increase when cold by the usual waxstat cable connected to an arm on the pump...

I think I need to strip it down a little and re check the cambelt is timed correctly - I wonder too if I managed to get the pump sprocket on slightly out? It does have a key but being a taper connection it might be possible to get it wrong and not notice..
1988 BX 19 Gti 16v
1991 BX 17 TZD Estate
1991 BX 17 TZD Estate