Fuel Filter replacement on a Mk2 2.5TD (4D56)

Fuel Filter replacement on a Mk2 2.5TD (4D56)

There are four bolts of about 10mm securing the Inter-cooler frame, 2 at the front near the radiator, two right at the back, remove all 4 and unplug the two cables at the rear on the right hand side, ease the Inter-cooler frame up and release the other two cables also at the rear. Now you are in a position to move the Inter-cooler out of the way, fold it over toward the left so that it ends up upside down.

Now you can see the Fuel filter fixed to the bulkhead at the back, if you run your hand down to the bottom you will be able to feel a wire coming out, trace this up the side of the filter and you will feel a connector fixed to the bulkhead, with a bit of fiddling you will be able to unplug the wires here, remember where it was was because it is difficult to see and you willl need to plug it back in later

Now, I use an oil filter chain wrench to remove the filter, it may be prudent to drain it first by placing something underneath and undoing the plastic wing nut drain off point on the bottom. Otherwise just go for it but be prepared for some spillage of Diesel. Having slackened it with a chain wrench, undo it the rest of the way by hand and remove from the engine bay.

Using a large adjustable spanner or gas pliers or similar undo the large white plastic lump fitted to the bottom of the unit with the wires sticking out. This plastic lump is your water separator/sensor/drain point. Clean it thoroughly as it tends to collect all the *beep* here.

Smear the rubber "O" rings at either end of the new filter with clean Diesel, fit the water separator/sensor unit, (do not over-tighten). Then fit the filter back onto the car, (again do not over-tighten).

On the top of the filter header unit bolted to the bulkhead, you will find what looks like a white plastic blanking cap, this is your priming pump, unscrew it, and pump it to fill the filter housing, (mine tends toi spit Diesel as I pump it).

Put the Inter-cooler back into place and replace the 4 bolts, then

Start it up

If the engine cuts out don't worry start it again, and if you need to turn it over on the key for a while is not the end of the world, this is just clearing any remaining air out.