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Rb20 Wont Start With Big Fuelpump?

slydn32

By slydn32,
in Engines & Forced Induction

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slydn32 Rookie

slydn32

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HI all , im kinda new to this online skyline stuff but hopefully some1 can help :)

ive got an rb20'd r31 skyline and am finding after putting a bigger fuel pump (out of my working gtr) in, it wont start easy untill ive cranked it for atleast a good 5 mins, with the timming a bit retarded to help. :)

once it starts it coughs and splutters (missfires and pops) untill 3000rpm onwards where it revs normal and makes that tough rb20 scream . Also when i actually drive it on the road not just nutral revs, it pulls hard past 3000rpm but same-same below that.

somthing i noticed though was a leak out the feed side of the fuel line just near the top of the fuel tank when at idle but not so much when it revs higher. leaks out onto the floor off the fuel tank :)

im thinking its that fuel line not holding presure or giving it too much presure??, can anyone think of a possible cause??

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jeffworld2 Veteran

jeffworld2

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Posted

if you DONT mean the little reg thing, then there is a split in the hose and the fuel that should be going to the motor is still in the tank/.

i suggest you pull it back out and check. A new bit of submersible efi hose is expensive but if you need it you need it. if you just make it shorter you may effectively lose some tank capacity. make sure you get a good seal with the rubber ring on the lid too.

and dont run the car with the fuel tank open looking at the pump :D

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