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Fitting a Walbro 255 in tank pump
As per the norm, if you f*ck it up because you followed my guide, its your problem, not mine!

Why would i want to change my fuel pump for a upgraded one?
Two reasons. Firstly, if you are going for bigger power, you can't get that power out of your engine unless your engine is getting the correct amounts of fuel at the correct pressures. The standard pump is good for 300ish bhp assuming its completely healthy. Mine was working happily on the standard engine but pegged out at 189bhp on the dyno.
Secondly, fuel pumps do give up and funnily enough, this walbro 255 (standard pump is also made by walbro) is actually cheaper than a standard pump!

What do i need?
BFO Flat head screw driver
Smaller flat head
side cutters
Old rags

Step 1
Remove the rear drivers seat base, lift the flap in the carpet and using a flat head, prise the black cap off to reveal the pump. As you can see in the photo, there is a plug, two fuel hoses and a big lock ring. Firstly, we want to release the lock ring which if its never been done before, is a complete bastard. Get your BFO flat head and use it to tap the lock ring around until it frees up and then you can just unscrew it. Now remove the plug and the two fuel lines (push the coloured clip in then pull hose off). One of the hoses will leak petrol which is in the lines so use your old rags to soak this up.


You can now remove the pump. You need to lift it out at a slight angle so as not to catch the level sender float but not too much of a angle as the pump housing will be filled with petrol and will spill all over your carpet and thats a smell you can't get rid of. Carefully remove the pump and pour the petrol into a container and also pump the gauze bag on the bottom to get rid of the fuel in there.

Step 2
You should now have this on your work bench



You will see there is 3 clips around the housing. Using a flat head, release these and pull the top of the housing away but not too hard as there is cables connected. The two small black cables are for the level sender and do not need to go back on in a certain way so remove these and then pull the pump and housing top out of the pump housing


New and old pump

Step 3
Remove the two power cables (taking note of which way around they go) and then simply pull the pump away from the top. Its just held in with a rubber ring.

Offer your new pump up and decide what your going to do. I found that the new pump outlet sits in the rubber ring fine but not as far so you need to support the pump (which i will show you how to expertly do later Wink ).
Fit the sound deadening sleeve to the pump (and like anal, this requires plenty of lube!), remove the rubber ring from the bottom of the old pump and fit to the new one and then fit the pump into the top. Chop the cables down, terminate them (i used normal spade connectors but removed the plastic insulation as i wasn't sure how it would react in petrol) and plug it in then offer it into the pump housing. Providing you have the inner moon shaped gauze inside the pump housing, the rubber seal on the bottom of the new pump should fit perfectly in this. Refit the cables for the sender then clip the top down. You will realise that the pump moves ever so slightly which we don't want so....


Bang a cable tie around it just to make sure its not moving about in the housing.

Refit the gauze bag on the bottom and fit the pump back into the car making sure to get the fuel lines around the right way (mine were colour coded so hard to get it wrong).

Turn the ignition to stage 2 and the pump will prime for a few seconds. May be an idea to do this a few times as the fuel will have run out of some of the lines so will need priming again. Start the car and make sure its idles steady. Yes? Good take it for a drive!
Team Eaton

1999 China Blue 306 GTi6 - Eaton Supercharged - 214.5bhp 181lbft
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A bin bag or other sheet of plastic spread around the hole means you can be a bit less careful with the fuel. In the top of the plastic cap there is a slot, inserting the the screwdriver and pulling away from the centre of the cap will release it without mullering the edges of the cap or the hole in the floor (learnt the hard way lol).
306 HDi Deathtrap - 130bhp / 220lbft

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thinking of upgrading on mine but I don't see why mine cuts out all the time I'm only running 152bhp would it help to upgrade?
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