injector pump rebuild ...

i'm having starting problems in that when left overnight she needs to turn over for 15 seconds or more before she'll start. Bit of white smoke, and after firing on one or two she'll runs OK. Starting immediately after a run (going to the shops for example) is OK. Leave he for a weekend and she takes 30 seconds turnin over before she stumbles into life.

I've come to the conclusion the injector pump is somehow losing pressure
, possibly because of an internal seal ??

I've seen seal/rebuild kits - Land Rover Defender, Freelander 1, R/R Classic Seal Kit for Bosch Injector Pump | eBay - anyone have any advise to offer .. ?

Check your leak off pipes are in good condition as they could be letting air in.

Kwakerman said:

Check your leak off pipes are in good condition as they could be letting air in.

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Would I not see fuel everywhere if they were leaking ??

miktdish said:

Would I not see fuel everywhere if they were leaking ??

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not always no

Replace your lift pump first ! They are quite poorly made and have two ball valves ! If fuel runs back to the tank it can take a few cranks to prime up the system !! I've changed lots of these !! Try not to buy a britpart a pump! They are rubbish , better off with an old series Lucas pump wich are rebuild able !!!

ferretboy said:

Replace your lift pump first ! They are quite poorly made and have two ball valves ! If fuel runs back to the tank it can take a few cranks to prime up the system !! I've changed lots of these !! Try not to buy a britpart a pump! They are rubbish , better off with an old series Lucas pump wich are rebuild able !!!

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I try not to buy anything Britpart ..... although it's easy to see why folk do. LR want circa £95 and the Britpart is £9.86. I see there is a Bearmach and a Delphi, the delphi also seems to be the AllMakes PR2 unit.

I'll try a Delphi and let you know

Thanks

If the leak off pumps are loose at the injectors, which they often can be, then overnight (or on a hill!) the fuel will drain back through the system. So check them there, copper washers as well

Generally speaking the Bosch VE injection pump used on tdi engines is very reliable and it would not tend to experience a sudden loss of injection pressure unless the cam plate is broken or all four delivery valves have somehow catastrophically broken up. There is ofcourse a pressure regulator fitted to the pump which can clog with dirt should debris find its way into the fuel / past your fuel filter but it is very unlikely and the engine would usually start after 3-4 turns either way.

The problem in your case sounds much more like air in the fuel caused by leak back. In other words, there may be a hole / fracture in a fuel line in the return side of the fuel system (injectors > injection pump > fuel tank). Split spill rail pipe work is usually the main suspect. If air can find its way into the fuel lines, fuel will inevitably run back to the tank and you will have to prime the system every time you start it, hence the reason why it is taking so long to fire up. Fuel will not necessarily find its way out of the hole where air is getting in.

You can perform a simple check to ensure that your lift pump is working correctly once the engine has fired up. With the engine running and maintaining a steady idle, slacken the 10mm bleed bolt on top of the fuel filter housing. You should find that diesel instantly starts to weep from the bleed screw. Do you see any bubbles in the diesel? If you can remove the bleed screw entirely without any sign of diesel emerging from the hole, your lift pump has likely given up the ghost or you have a severe fuel restriction in the fuel line (clogged filter / clogged pickup pipe / pickup pipe gauss) or potentially even a hole in the pickup pipe allowing air to be drawn into the system before the fuel pump).

Do you see white smoke from the exhaust when the engine is turning over and then for about the first ten seconds or so after the engine has fired up?

Be weary of Delphi lift pumps - they are not a quality item by any means. Unfortunately they have fallen victim to outsourcing and subpar manufacturing just like many other 'respectable' manufacturers, Bosch included. I have had five fail on me within the last two years, two of which ****ed diesel straight into the sump diluting my oil.

-Tom

People! Calm down, lift pumps, fractured pipes, 10 paragraph replies and only one of you gave the best information.

Kwakerman was right on the money - it would also cost the OP about £2-4 to test out this theory and probably about 4 minutes of his time.

Miktdish - to put you in the picture, I went down to my Disco one morning, turned the key, crank crank let go of the key as it's habit it hasn't started. Try again and hold the key until it fires which it did eventually. Drove straight to the motor factors and bought a set of pipes for I think £4 (that's expensive for this pipe too!).

Found one to have cracked where it joins the metal union. Replaced them outside the shop and went about my day as normal. Following day, started as normal first time.

miktdish said:

Would I not see fuel everywhere if they were leaking ??

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As stated elsewhere you can get an air leak without a corresponding fuel leak. Its down to the molecule sizes of air and fuel - just think about Gortex (other breathable fabrics are available, but I can't think of one at the moment!) it lets air in but keeps water out due to the size of the weave. It lets smaller molecules (air) through but not the larger fuel ones.

miktdish said:

Would I not see fuel everywhere if they were leaking ??

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With the leak off system there is not really any pressure, the diesel just trickles back to the tank, that isn't really the problem, the problem is when the system is in vacuum, that is when the engine is off, gravity trying to push the diesel all back to the tank, a perfectly sealed system means nothing but diesel can enter the system, so it stays primed. Let air in at the top and the system can drain.

The return line also ties into the pump, once the negative pressure starts to work on the pump return you end up with diesel syphoning out the pump too and air bubbles going up into the top of the pump. It is amazing how much air can enter the system over night.

Just count yourself lucky you have a Bosch pump, if it was the Lucas it would NOT self prime as it relies on an entirely air free feed of fuel. Even a bubble of air will put a Lucas pumped engine out like a light.

pos said:

Generally speaking the Bosch VE injection pump used on tdi engines is very reliable

The problem in your case sounds much more like air in the fuel caused by leak back. In other words, there may be a hole / fracture in a fuel line in the return side of the fuel system (injectors > injection pump > fuel tank).

Do you see white smoke from the exhaust when the engine is turning over and then for about the first ten seconds or so after the engine has fired up?

-Tom

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Hi - sorry for the late response, i've been away for a few days ...

Yes I do see a some white smoke as you describe and from your (and others) comments i'll be checking the fuel/spill line tomorrow.

Thanks

Kwakerman said:

Check your leak off pipes are in good condition as they could be letting air in.

Click to expand...

Hi

Yup - that was it. new pipes across the top of the engine (between the injectors) and it's fixed.

Thanks for your help....

Kwakerman said:

Check your leak off pipes are in good condition as they could be letting air in.

Click to expand...

Hi

Yup - that was it. New pipes across the top of the engine (between the injectors) and it's fixed.

Thanks for your help....