Replacing a 300TDi lift pump.

[Les Henson]

The easiest way to check if the lift pump is working is to open the bleed screw on the top of the filter housing a few turns and then spin the engine on the starter. If nothing comes out, then the pump is suspect (although the supply pipe could be the culprit as well). Anyway, lets assume the pump has had it, so this is the way to replace it. You will need 2x14mm 'C' spanners, a small hacksaw or file, some grease or RTV sealant, and a 10mm socket on a medium extension bar (3/8" or 1/4" drive are fine, but I don't think 1/2" drive will get at both bolts).

The location of the pump is on the drivers side of the engine - behind the injector pipes and injector pump.

The two 10mm head bolts that hold the pump to the block are pretty tucked away.

Apart from the pump, you will need two olives and a gasket (it might come in the box with the pump, so check)

The pipe fittings are known as a compression fitting - in that a male and female connector screw into each other and compress an olive on the pump pipes, thereby effecting a seal. You need 2 x 14mm 'C' spanners to undo them. Hold the male fitting still and undo the female (the one closest to the pump). Make a note of which pipe goes where - there is an arrow on the top of the pump, which indicates fuel flow, so top pipe comes from the tank, and bottom pipe goes to the fuel filter.

A 10mm socket on either a 3/8" or 1/4" drive medium bar will just fit through the injector pipes as shown.

The left hand bolt is easier.

The pump will then lift away - upwards at an angle. Hopefully the gasket will be stuck to the old pump, but if not - remove it from the block.

The female fittings need to be re-used, so cut or file the through the old olives and recover them.

Put the female fitting on the new pump, then put the olives on (they will be a loose fit at this point)

Stick the new gasket to either the pump or the block - using grease/rtv sealant, etc.

Fit the pump at the same angle as removing the old one - keep it high so that the foot of the pump goes on top of the cam. It's likely that the pump will not sit flush with the block face, as the cam lobe will be in the way and you will be pressing against the pump spring when you bolt it back on.

Bottom pipe first (from the filter). Keep the fitting pushed towards the pump and tighten the two fittings in the same way as for removal. There will be some resistance as the olive is crushed against the pipe, but don't go too far or you will strip the threads. Once the fitting won't move on the pipe, then leave it as it is and wait to see if it leaks and tighten a bit more. Do the same for the top pipe (to the tank)

There's a primer lever on the bottom of the pump - open the bleed valve and then pump the fuel (press downwards) until it comes out of the bleed screw and then tighten it. If there's no resistance on the lever, then flick the starter and try again until the lever will work properly. Once bled, lift the lever up and it should stay there.

Start the engine and look for leaks - carefully tighten the compression fittings until they stop.

Les.

[TheRecklessEngineer]

Excellent as always

Can I add to this that you can remove the two outermost injector lines to make access easier. 17mm spanner fits the injector unions - only takes 5 mins to take them off and makes it easier to both remove the pump and get to the 10mm bolts that hold the pump to the block. You do need to take special care not to let any dirt into any of the open connections.

Don't forget that it will only fire on 2 cyls for a few moments when you start it after removing and refitting these lines.