Fuel pump issue

Moderator: Moderators

Post Reply
asandilands69
Posts: 45
Joined: Sat Jul 08, 2006 5:04 pm
My Bike: ZXR400 SP / R1
Location: portsmouth

Fuel pump issue

Post by asandilands69 » Mon Dec 10, 2018 2:32 pm

Hi everyone, just need to pick your brains please! Picked up a little Christmas project non-running L1 last night. Previous owner reckons he had it running fine after a carb clean, but the. suddenly stopped. After a quick look today I’ve found the fuel pump isn’t running...I’ve tried another pump and another pump relay, making no difference! Any other suggestions?

User avatar
banner001
Track day God
Track day God
Posts: 2328
Joined: Sat Sep 24, 2011 3:27 pm
My Bike: ZXR400 L4
Location: Nuneaton

Re: Fuel pump issue

Post by banner001 » Mon Dec 10, 2018 6:28 pm

First thing is check with a battery that your fuel pump is actually working and pumping fluid.

If it is then remove the fuel pump relay and now connect the red wire that would go to the fuel pump relay to where the black/blue wire is on the fuel pump, then connect the other wire from the fuel pump to ground. Now your fuel pump should run continuously once you set the bike's kill switch to ON.

If these both work then you know that most of your wiring is fine and that the pump is fine, it's then got to be a relay issue, or the wiring related to the relay. Full colour wiring diagram is in the electrical section.
UK ZXR 400 L4
UK ZXR 400 L3 track bike
1989 FZR 1000 EXUP-R streetfighter

asandilands69
Posts: 45
Joined: Sat Jul 08, 2006 5:04 pm
My Bike: ZXR400 SP / R1
Location: portsmouth

Re: Fuel pump issue

Post by asandilands69 » Sat Dec 29, 2018 1:32 am

Sorry for the slow reply Banner, only just seen this. An auto electrical friend of mine popped round to take a look for me, but with little joy. He did quickly confirm that the pump itself was fine, although the relay was not working. He sorted the relay issue by cleaning the contacts, but this still didn’t spring the pump in to life. From the limited view of the wiring diagram I was able to print he was able to confirm that everything seemed to check out fine, with the exception of the right switch gear...which he was unable to properly check due to the wiring diagram being too difficult to read. I haven’t yet ordered another set of switches to try it, but could those switches be causing the problem whilst still allowing the bike to turn over? The only other possible issue we did find was a dodgy stand switch bypass, which for some reason also has a neutral switch green wire joining in with the two stand switch wires...

User avatar
banner001
Track day God
Track day God
Posts: 2328
Joined: Sat Sep 24, 2011 3:27 pm
My Bike: ZXR400 L4
Location: Nuneaton

Re: Fuel pump issue

Post by banner001 » Sat Dec 29, 2018 9:06 am

You should have continuity between:
Red wire on relay to red wires on coils and both red wires on RHS handlebar connector block.

Black wire on relay and black wire on coil.

Yellow/red wire on relay to yellow/red wire at fusebox and to yellow/red wire on starter solenoid.

Black/blue wire from relay goes directly to red wire on fuel pump.

Black wire on fuel pump goes to ground.

Thanks all that's on there, if wiring looks good I would still suspect the relay unless you took one from a known working bike.
UK ZXR 400 L4
UK ZXR 400 L3 track bike
1989 FZR 1000 EXUP-R streetfighter

User avatar
banner001
Track day God
Track day God
Posts: 2328
Joined: Sat Sep 24, 2011 3:27 pm
My Bike: ZXR400 L4
Location: Nuneaton

Re: Fuel pump issue

Post by banner001 » Sat Dec 29, 2018 9:12 am

Also, as your bike is turning over it can't be a starter lockout, or RHS switchgear issue...so it has to be relay or internal wire break.
UK ZXR 400 L4
UK ZXR 400 L3 track bike
1989 FZR 1000 EXUP-R streetfighter

asandilands69
Posts: 45
Joined: Sat Jul 08, 2006 5:04 pm
My Bike: ZXR400 SP / R1
Location: portsmouth

Re: Fuel pump issue

Post by asandilands69 » Sun Jan 06, 2019 7:04 pm

Brilliant, thank you.

Post Reply