cav pump query

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barry badger
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cav pump query

Post by barry badger » Sat Apr 11, 2015 4:41 pm

I've been fiddling about with the lucas injection pump settings on my tzd.
Although it starts ok and power is good it was a little bit smokey on heavy acceleration ( blue/grey ) and a little noisy at mid revs.
So i've retarded the timing very very slightly, increased the fuelling slightly and shortened the double ended linkage (the one with the white and blue ball joint) by about 3mm. This was all done by trial and error with lots of road testing in between adjustments. The result is, the smoke is much reduced although i'll be able to tell by how much in the dark with the traffic behind me and the engine is smoother and quieter. power seems pretty much the same.
Basically what i want to know is what does the unit on the back of the pump (the one whose linkage i've adjusted) do?
Is it the advance and retard? and if so by shortening the linkage have i advanced or retarded it?
1993 tzd estate, on sorn
1992 tzd estate, slowly being raided for parts
1992 txd estate, "doom blue" on the road
1991 4x4 estate, on the road

pwykes
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Posts: 43
Joined: Mon May 21, 2012 6:35 pm

Re: cav pump query

Post by pwykes » Tue Apr 14, 2015 8:27 am

Have you seen this on ebay i am going to buy it at some point.
Cav DPC Fuel Injection Pump Workshop Manual ( Lucas Cav ) DVD

Cheers phil.

citronut
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Joined: Wed Oct 31, 2007 7:55 am
Location: EAST SUSSEX UK

Re: cav pump query

Post by citronut » Tue Apr 14, 2015 9:31 am

is your wax stat working, if it is stuck in the cold start position ( cable taught ) this will hold the fast idle/cold start lever on and also keep the contacts for the advance/cold start servo in the closed/on postion,

the above will cause over fueling and alters the pump advance, which can cause your symptoms

regards malcolm
curent ride
K reg BX 17TD TZD est
also own
K reg D special

no longer have
H reg CX saffari 2.5 TRI (now gone to Malaysia)
R reg xantia 1.9TD est (gone to meet its maker)