Another 200tdi lift pump mystery

So I've been having air in the diesel problems. My beloved 1985 110 was running fine but I could only get it to start if I manually bled the system. Replaced the fuel filter, some dodgy looking pipes, overhauled the wiring for the solenoid and still the same. Undid the tube from the lift pump to the filter, turned it over and nothing. Manually pumped, diesel everywhere. Took off the lift pump, shoved the pipe from the tank in some diesel, moved the curved cam lever up and down and it worked fine? Looked at some posts on Landyzone and discovered that the plastic rubbery spacer shouldn't be fitted on a Discovery 200tdi engine. Refitted the lift pump without the spacer and the engine now works fine. HOWEVER, I fitted the engine 8 years ago and it's always worked brilliantly 'til now. How is this possible? Did the fuel injection pump have enough pull to get sufficient diesel or am I missing something? Would love an explanation if anyone's got one.
P.S I am certain there is no electric pump fitted.

Eight years without a lift pump wern't workin because of the spacer ! Short stroke ! if that makes sense ? Now you have FULL stroke so will work BETTER ! for how long i don't know

The injection pump on a 200tdi can compensate for a failed lift pump but not great for your injection pump (or so I've been told). Fuel pump, run off lines and fuel filter are common places for air to get in.

So with the spacer I would get a short stroke, what maybe 50 % pull or something, and the wonder that is the Bosch VE did the rest. Maybe now that it's starting to get old ie 23 years to be precise, the VE just hasn't got the strength any more. However when I turned it over with the pipe disconnected from the lift pump to the filter not a drop came out which suggests it wasn't working at all. Thinking about it now I've never been able to bleed the system automatically (until yesterday that is) it's always needed doing manually and I am sure it never affected the performance until recently. I've had it over 85mph on the flat without a tail wind which I reckon would be about impossible without a fully functioning diesel system. Why would it have the spacer fitted anyway, just the previous owner of the the '93 Discovery donor vehicle fitted it by mistake? So having the spacers shortened the life of the VE but it's still managed 23 years. Tomorrow is the ITV (Spanish MOT) so we'll see how the emissions are but it would be worth every penny of the rebuild. It was running sweet this evening in the freezing cold without a trace of smoke. I love tdi's.

defandi said:

So I've been having air in the diesel problems. My beloved 1985 110 was running fine but I could only get it to start if I manually bled the system. Replaced the fuel filter, some dodgy looking pipes, overhauled the wiring for the solenoid and still the same. Undid the tube from the lift pump to the filter, turned it over and nothing. Manually pumped, diesel everywhere. Took off the lift pump, shoved the pipe from the tank in some diesel, moved the curved cam lever up and down and it worked fine? Looked at some posts on Landyzone and discovered that the plastic rubbery spacer shouldn't be fitted on a Discovery 200tdi engine. Refitted the lift pump without the spacer and the engine now works fine. HOWEVER, I fitted the engine 8 years ago and it's always worked brilliantly 'til now. How is this possible? Did the fuel injection pump have enough pull to get sufficient diesel or am I missing something? Would love an explanation if anyone's got one.
P.S I am certain there is no electric pump fitted.

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The injection pump may have coped for all these years because the fuel system was OK, then an air leak developed and sucking from the injection pump means an air leak in will cause issues possibly even letting a lot of diesel run back to the tank overnight leading to starting issues etc (especially since your lift pump wasn't helping), now your pump is pumping and the injection pump is being fed diesel at a low pressure, so the small hole or leaky union or filter head where air was going in is now under pressure. It may not even leak diesel out, air can pass through a very small hole, that fuel may not pass.

I would at this point do a fuel system revamp if you think your lines look iffy.

Dont forget the VE actually has its own pump built in and can pump a surprising distance and height all on its own, many cars only use the VEs built in pump, I think LR added lift pump for adverse angles etc
Iirc the internal pump maintains a pressure in the VE inj pump of approx 70psi so its no lightweight.