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Replacing S13 fuel pump

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One common problem a lot of silvias have is that the fuel pumps die in them. Fair enough to, the cars are near on 20 years old in some cases. Changing the fuel pump to an aftermarket item should be on the top of the modification list for every silvia owner.




I picked up a Walbro 255L/Hr pump from ebay for $155.75 delivered. This pump should be good for around 500HP, which is enough for most people. Even though a GTR pump will bolt straight in or you can use toher 2nd hand pumps, I recommend getting a new aftermarket one because they're not all that expensive and it will (hopefully) guarantee a longer working life. Ok getting started:




Step One




Disconnect the connector going into the fuel pump in the boot or remove fuse for pump if theres one (i cant remember without goin to have a look). Attempt to start the car until it doesnt want to run anymore (this is nescessary to remove the pressure from the fuel lines). Remove the negative battery terminal.




Remove the fuel lines and take the pump out of the tank. Its goin to get fumy so do it in a well ventilated area. Be careful when removing the pump, the float may get in the way. Dont force anything itll come out.




Step Two




Now the pumps out, remove the standard pump from the bracket. Its pretty straightforward, undo the screws for the electrical connections, remove the zip tie, remove the clips holding the rubber pipe and twist the rubber pipe while pushing the pump up out of the bottom L Bracket.




The Problem now is that the Fuel pickup on the walbro pump is a little higher than the original one, you dont want to run out of fuel before the gauge shows empty so it needs to go where the original pickup was. I measured it to be about 20mm too high. This doesnt have to be an exact/precise measurement however, too low it can wear on the bottom of the intank filter and suck up crap into the pump, too high you'll run outta fuel before the gauge hits empty.




Step Three




If you look carefully you can see that the bottom "L" bracket has been spot welded on. You need to drill these out. Before you do it might be wise to remove the sender unit to keep it out of harms way (one screw, but its slotted for adjustment so might be an idea to mark the location before unscrewing it). Also mark the top of the L shaped bracket so you can Measure 20mm down from that mark.




Its only necessary to drill the thickness of the first material not through the lot (but you can if you want). Then use a flat screwdriver wedge it between the two to crack it apart.




Step 4




Measure the 20mm down for where the new position for the top of the bracket will go. I then spot welded it there (I had a mig welder) but its prob easier (and safer) to drill new holes and rivet it into place (i didnt have a rivet gun).




Desolder the positive lead from the pump holder and solder in the supplied lead. Do the same with the negative lead. They also provide connectors so you could cut the old leads and crimp the new one onto it, but i recommend soldering it for a much better and stronger connection. From here its a matter of following the installation guide that comes with the pump.




Step 5




But i'll explain the Walbro one quickly anyway. Connect the supplied rubber hose onto the pump with the supplied hose clamp. Slide the other hose clamp over the hose and push the hose onto the appropriate metal line on the pump bracket (you can cut it to a shorter length but its only about 1cm longer i didnt bother. Place the pump filter onto the pump and the fuel isolator (rubber insulator thing) over that and place into the "L" bracket. Push the Rubber hose down the metal pipe so the pumps firmly held in the isolator and tighten the top hose clamp. Dont forget to put the sender unit back on. Use a zip tie to provide further support for the pump and its done.




Step 6




Replace the pump into the tank, in reverse to removing it. Connect the pump back up to the fuel lines and power connector. Connect the battery.


I have an aftermarket fuel regulator with a gauge on it that i'll be installing aswell so i can set that to the factory spec pressure (28psi , 2.0 kg/cm^2 at idle for my ca18det)








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is that the process the same as with bosh pumps? Also, what is defined as the best when it comes to fuel pump/ system set up?

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There Really is no best, as many people need different setups for their purpose, nice writeup mate

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