Walbro GSS342 (High Pressure 255lph) fuel pump Install
Why Needed?: If you want more than 65HP in nitrous, or do a major supercharger/turbo upgrade.
Price: It can be picked up for $85 shipped, look around on the net (i.e. eBay) for performance shops and e-mail them directly with an offer.
Performance Potential: This pump will handle all of your upgrade needs pushing well over 100psi-enough for well over 400BHP.
Fitment Issues: This unit is the pump ONLY and will require the use of the stock pump housing and filter. It is nearly* a direct plug-in replacement for our stock pump.
*The pump has some small plastic spacer tabs on the top and bottom that need to be grinded off to fit inside our stock housing correctly. (Anyone with 2 minutes and a grinder can achieve this.)
You will also need get a new gas tank o-ring seal from your local Nissan dealer ($9).
PRELIMINARY STUFF :
WORK IN A WELL VENTILATED AREA!
?Remove the FUEL PUMP FUSE from the fuse box underneath the dash.
?Start the engine to use up the remaining fuel under pressure in the fuel line. Wait for engine to stall.
?Re-start a couple times to make sure you have gotten as much fuel out as possible.
?Open fuel door and take off gas cap to release air pressure in fuel tank.
?Disconnect the GROUND CABLE from car battery.
?Reinstall fuel pump fuse back into fuse box.
OEM FUEL PUMP REMOVAL :
?Remove REAR SEAT CUSHION by pulling both RELEASE RINGS underneath.
?Remove the THREE 8mm (or Phillips screw head) bolts holding on the TOP COVER.
?Disconnect the 1 ELECTRICAL HARNESSES from the top.
?The top of the fuel tank is very DIRTY. To minimize the possibility of contaminating the fuel tank, CLEAN using brake cleaner. Wipe off excess and allow to dry.
?Disconnect both HOSE CLAMPS securing the 2 fuel lines leading to fuel tank. The fuel line on the right hand side (driver) will be the one with the fuel coming out. So have some rags handy as some fuel will come out of that hose.
?Remove the SIX 8mm BOLTS holding on the securing ring. Remove the RING and set aside.
?Slowly fuel pump assembly, with extra care of the arm of the fuel sending unit.
BE VERY CAREFUL NOT TO DROP ANYTHING IN THE FUEL TANK (LIKE THE O-RING)
?Using a flat-head screwdriver to remove the fuel level sender. You will be able to see the fuel pump assembly underneath. Using a flat-head screwdriver, carefully, pry off the 3 LOCKING PORTIONS of the "basket" to FREE THE TOP HALF. This part requires some time and finesse. As you are lifting the top half off you will be able to unplug the electrical plug on top of the fuel pump
?Carefully turn the FUEL PUMP AND PICKUP assembly counterclockwise about 90o and lift to remove. Note the position of the hose and pickup for later reassembly.
RE-INSTALLATION OF FUEL PUMP :
?COMPARE the OEM and Walbro fuel pump.
?Carefully grind off the tabs that are on the top of the Walbro to allow the clip to fit. (this is very easy and should not take you more than 20 min at the worst)
?Carefully remove the pickup assembly RETAINER. Remove the pickup assemble. If pickup SCREEN is dirty, clean it. REINSTALL the pickup assembly onto the Walbro in the same position. Make sure the pickup is firmly attached to fuel pump!
?Carefully replace new Walbro/pickup assembly back into lower "basket" assembly. The lower portion of fuel pump needs to be positioned first, then you can push down slightly to get top portion to FIT SNUGLY.
Make sure to line up the bottom fuel line when pushing down. If it is not positioned correctly, the WHITE BRACKET COVER TOP will not snap back in correctly. Do not force. You may have to grind some more on the tabs of the pump.
?Replace the top of the fuel pump assembly. Make sure that the tabs snap back in place.
?Replace the fuel level sender until it snaps back in place.
?Replace old gas tank O-Ring with new O-Ring.
?Reposition sender assembly over gas tank by rotating it correctly over mounting.
?Slowly lower seat assembly over gas tank and O-Ring. There should be no resistance or fuel hose may be kinked underneath. Refasten/torque the SIX 8mm BOLTS to specifications over the RING bracket.
?Reconnect the 2 hoses and HOSE CLAMPS to assembly top. If you mistakenly swap these, the engine will not start. They should line up the proper fuel line as one is shorter than the other.
?Reconnect the 2 ELECTRICAL HARNESSES.
?Refasten the TOP COVER.
?Reconnect ground on car battery.
?Start car and check for any fuel leaks. If you have any you will know immediately. (you may want to drive a round a little with the windows open to air it out)
?Replace REAR SEAT.