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Fuel pump woes (again) Mon Feb 20, 2017 2:37 pm
RussK100
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Hello everyone, I'm hoping I can pick your brains as I'm at a bit of a loss.
Last year my fuel pump packed in, I replaced it with a Mapco one and all was going fine. Strangely, it may have continued to run after the killswitch had been engaged on a handful of occasions, which may be relevant here.
Long story short, I ran the tank dry and a few miles down the road after topping it up the bike died. It'd crank, but not run. I suspected the fuel pump might've had it again.
I've got the pump out and on the bench and if you give it 12v it spins. So that's fine.
I've checked the relay and it clicks, so I'm guessing that's fine. There's 12v at fuse 6, so all's well there and when I crank the starter I get 12v (or thereabouts) to the green and white wire on the connector that goes into the tank. So power is making its way to where it should be but the pump definitely doesn't run when connected to its wires in the tank. Should voltage go to any of the other wires on this connector whilst the starter is cranking?
I see from the wiring diagram that the feed and earth to the pump appear to come out of the level sender in the tank, so would I be right to assume that the sender is faulty? Is this a common issue or anything any if you have experienced before, and what am I looking for when troubleshooting it?
Any help would be hugely appreciated, the bike is a 1985 K100 RT.
Cheers!
Last year my fuel pump packed in, I replaced it with a Mapco one and all was going fine. Strangely, it may have continued to run after the killswitch had been engaged on a handful of occasions, which may be relevant here.
Long story short, I ran the tank dry and a few miles down the road after topping it up the bike died. It'd crank, but not run. I suspected the fuel pump might've had it again.
I've got the pump out and on the bench and if you give it 12v it spins. So that's fine.
I've checked the relay and it clicks, so I'm guessing that's fine. There's 12v at fuse 6, so all's well there and when I crank the starter I get 12v (or thereabouts) to the green and white wire on the connector that goes into the tank. So power is making its way to where it should be but the pump definitely doesn't run when connected to its wires in the tank. Should voltage go to any of the other wires on this connector whilst the starter is cranking?
I see from the wiring diagram that the feed and earth to the pump appear to come out of the level sender in the tank, so would I be right to assume that the sender is faulty? Is this a common issue or anything any if you have experienced before, and what am I looking for when troubleshooting it?
Any help would be hugely appreciated, the bike is a 1985 K100 RT.
Cheers!
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Lurking in the garage: 1986 BMW K100RT & 1991 BMW E30 M52 converted 318iS