How To: Replace Fuel Pump with performance Pump

[Bowders1]

Seen a few guides on replacing fuel pump but typically they are just a complete swirl pot swap.

 

The MK1 Octy VRS or other petrol variants have a "In Tank" fuel pump . i.e it sits inside the fuel tank rather than externally 

 

The Pump itself sit's inside a housing . (also known as a Swirl Pot ).

 

This housing hold's the Fuel Level sender on it.

 

The Housing / swirl pot is used to both feed the fuel pump and collect fuel returned from the engine,  It s used to prevent fuel surge as you normally get with a big tank which interrupts the engines fuel supply under extreme cornering. It is kinda like a mini fuel tank in the Main fuel tank.

 

This guide shows how to replace just the Pump with a aftermarket performance pump.

 

Although they are meant to be a direct replacement, they do need some extra effort to install

 

Here is the Pump I purchased a Sytec intank pump. They are rated at 5bar (std 3bar)

 

 

Make sure you have a load of rags to soak up fuel, as some will leak out when pump is removed

To be on the safe side, remove fuse for fuel pump (Fuse 28) or Let car stand overnight so no pressure is in system.

I also recommend you do not do this with a full fuel tank as car is on a slope you will loose fuel and also makes job a lot harder coz you will have a full d if you are Housing full to brim with fuel.

- If you have driven defo pull Fuse 28 , start  engine and let it die
- Disconnect Battery negative terminal
- Lift up rear seat (Bench Seat)
- Lift up carpet covering under bench seat
- You will see a triangular/circular metal black plate with 3 screws

 

- Put rags around the seat area where the Pump will be pulled out to soak up any dripping fuel

- Undo all three screws and remove plate
- Remove 4 pin connector and fuel hoses x 2, they are clipped in, press in the tab at base of hoses's and fuel hose  will pull off of pump.

- Remove / unscrew black Union Nut (Its that Huge black ring thing with grooves holding pump housing in place ), i was able to use a large flat screwdriver and tap the sections using hammer to carefully start to ring to turn. Then finish undoing with hands

-  Carefully Lift the fuel pump housing (swirl pot) and also slightly tilt it to allow removal of float (fuel level device)
-  now you should be able to get the whole thing out, let it drain of fuel by slowly then fully  lifting out of Fuel Tank.
 

- Pump / housing removed (can see the black rubber seal that seal the pump in tank)

 

 

 - hole where pump used to be….This is why I stated don't have a full fuel tank....

 

- This is the actual Sytec pump alongside the original pump. As you can see they are a direct match

 

-  To replace Pump you will have to separate the Fuel pump housing

 

- First separate the Float asm / back plate from Housing x 4 torx screws

 

 

Removing these screws and then use a flat screwdriver to lever up the cap from the lugs and then you will be able to separate the top / back section from base and pump will still be attached.

 

Take note of the rubber seal that is in the bottom base of housing(or maybe still attached to bottom of pump, and also the top seal that you will see when separate pump from top of housing. You should get these 2 seals with the new pump.

 

 

 

- Unplug the 2 wires from top of pump.

 

 

-  Now you will need to remove the old connecting fuel hose from pump and housing connections. These are just a push fit, but they are tight for obvious reasons and have been on pump since produced so good luck in removing them.

I would say be prepared to replace this as these are pita  and chances are you will end up damaging

 

-  Here is the spare fuel hose I purchased (210mm as that is the only smallest size I found) Std size is 170mm. 

 

 

Typically you can't buy this from dealers as you will have to buy complete fuel pump asm/housing. So get from same place as Sytec pump or look on ebay. 

 

Alternatively you can purchase "in tank" black rubber fuel hose and just cut to length. Ensure it is "in tank" and not external fuel hose else the hose will melt.......(needs to be 7mm dia)

 

I have used the black hose before on these pumps(Walbro on left LCR on right)

 

 

 

Also they are one time use jubilee clips so you will need to have spare jubilee clips or some cable ties(i used jubilee for safety)

 

- press out pump from remaining  housing (only held in by the top rubber seal)

 

 

- Hose removed from pump

 

 

- After fuel hose removed now get new pump and install it in reverse . Use the 2 new pump rubber seals. word of advise these will make pump stiff to push fully down into bottom base. use a little oil to help seal pop in.

 

VERY important. The pump must sit fully home. and the bottom pump must mate up with the plastic lower section on pump housing. If not you will find the car hard to start due to the fuel not remaining in the swirl pot as it will seep back into tank through the small gap between pump and bottom housing.

 

This bit....

 

 

If you car is hard to start that is your problem (unless pump faulty)

 

- hose's connected

 

 

- finished asm.

 

 

- When installing back in car ensure the black housing seal is fully located between pump and and not caught. Also again tilt pup slightly to get float sender into tank,

 

IMPORTANT - make sure you line up the arrow on pump housing to back of tank / seat.

 

 

Hope this helps

[kentphil1]

Good write up, top stuff as usual.

 

Is the Sytec any louder in use at all?.

[TTJD]

Very good tutorial on pump change 

I am wondering why did you change from  a 3 bar to a 5 bar , what was the advantage - did you notice any difference in performance 

Cheers