Fuel pump not priming

floyd · 24-05-2023, 09:02 PM

My s2r 800 isn’t starting and can’t hear the fuel pump priming up, I have power up as far as the connector, beyond that I don’t know without looking inside.
I know a wire break is quite common on the wires going through the resin.
Hoping that’s it’s just a failed fuel pump, any other ideas?
So I’ve never changed a fuel pump so any advice would be appreciated.
Is it just a matter of draining tank and undoing the flange underside of tank and pulling the whole unit out? I guess that from there I can test the wiring?
Any help would be appreciated

Luddite · 24-05-2023, 09:15 PM

Yes, that is all there is to it!

The injector relays have been known to fail but as you say you have power at the connector that rules that out.

Before you start, get yourself a replacement o-ring for the flange itself and also consider changing the fuel filter while you're in there.

The problem with a wiring break here is that it can often be intermittent making checking difficult. It sounds like yours has completed failed though, which should make testing more straightforward.

floyd · 24-05-2023, 09:20 PM

Thanks for the reply, I’ve ordered a o ring and a new pump , yes I’ll order a new filter too
Do I need to fully remove the tank or can I remove its internals with it propped up

Luddite · 24-05-2023, 09:49 PM

If I remember correctly from my S2R, you can leave the tank in situ but I think it's easier, and probably quicker, to take the tank off completely.

Darren69 · 25-05-2023, 12:56 AM

What he said, if not the relay then drain tank annd remove will be a lot easier to work on.

25-05-2023, 05:06 AM

I,’ll second the above!, having worked on mine more than I would like to, drain and remove is the way to go.

adie851 · 31-05-2023, 02:31 PM

Take the tank off the bike ,drain the fuel..give it a good clean out whilst you 're going inside the tank. Replace all the seals if possible...test the pump on the bench with a battery...like others have said ,replace the filter. All good advice. Could be wiring or a dodgy relay....

floyd · 05-06-2023, 06:04 PM

UPDATE .. in the end it was the pump harness that passes through the flange , I dug the resin out to reveal loose wires, was going to resolder but in the end decided to buy a new one..
https://www.ebay.co.uk/itm/234413828...mis&media=COPY
Needed to solder extra earth on this connector, maybe that is unique to the s2r as this is from a 620
On a footnote I had 12 flashes from front right indicator when I shut the bike down, been happening the last few months
No flashing now so guess must have been the ecu telling me there was a issue with the wiring/pump ��

24-05-2023, 09:02 PM	#1
floyd Registered User Join Date: Dec 2011 Location: bury st edmunds Bike: S2r Posts: 114	Fuel pump not priming My s2r 800 isn’t starting and can’t hear the fuel pump priming up, I have power up as far as the connector, beyond that I don’t know without looking inside. I know a wire break is quite common on the wires going through the resin. Hoping that’s it’s just a failed fuel pump, any other ideas? So I’ve never changed a fuel pump so any advice would be appreciated. Is it just a matter of draining tank and undoing the flange underside of tank and pulling the whole unit out? I guess that from there I can test the wiring? Any help would be appreciated

25-05-2023, 12:56 AM	#5
Darren69 Transmaniacon MOC Join Date: Sep 2013 Location: Sutton In Ashfield Bike: Multiple Monsters Posts: 6,091	What he said, if not the relay then drain tank annd remove will be a lot easier to work on. __________________ Roast Beef Monster! Termignoni and Bucci - Italian for pipe and slippers! S4 Fogarty, S4R 07T, 748, Series 1 Mirage

24-05-2023, 09:15 PM	#2
Luddite Registered User Join Date: Aug 2011 Location: Southampton Bike: M1100evo Posts: 2,465	Yes, that is all there is to it! The injector relays have been known to fail but as you say you have power at the connector that rules that out. Before you start, get yourself a replacement o-ring for the flange itself and also consider changing the fuel filter while you're in there. The problem with a wiring break here is that it can often be intermittent making checking difficult. It sounds like yours has completed failed though, which should make testing more straightforward.

24-05-2023, 09:20 PM	#3
floyd Registered User Join Date: Dec 2011 Location: bury st edmunds Bike: S2r Posts: 114	Thanks for the reply, I’ve ordered a o ring and a new pump , yes I’ll order a new filter too Do I need to fully remove the tank or can I remove its internals with it propped up

24-05-2023, 09:49 PM	#4
Luddite Registered User Join Date: Aug 2011 Location: Southampton Bike: M1100evo Posts: 2,465	If I remember correctly from my S2R, you can leave the tank in situ but I think it's easier, and probably quicker, to take the tank off completely.

25-05-2023, 05:06 AM	#6
Moco1961 Guest Posts: n/a	I,’ll second the above!, having worked on mine more than I would like to, drain and remove is the way to go.

31-05-2023, 02:31 PM	#7
adie851 Member Join Date: Jan 2015 Bike: S4r Posts: 104	Take the tank off the bike ,drain the fuel..give it a good clean out whilst you 're going inside the tank. Replace all the seals if possible...test the pump on the bench with a battery...like others have said ,replace the filter. All good advice. Could be wiring or a dodgy relay....

05-06-2023, 06:04 PM	#8
floyd Registered User Join Date: Dec 2011 Location: bury st edmunds Bike: S2r Posts: 114	UPDATE .. in the end it was the pump harness that passes through the flange , I dug the resin out to reveal loose wires, was going to resolder but in the end decided to buy a new one.. https://www.ebay.co.uk/itm/234413828...mis&media=COPY Needed to solder extra earth on this connector, maybe that is unique to the s2r as this is from a 620 On a footnote I had 12 flashes from front right indicator when I shut the bike down, been happening the last few months No flashing now so guess must have been the ecu telling me there was a issue with the wiring/pump ��