Fuel Pump Runs Continuously When Ignition is on.

[FlatBow]

Hi, I have dragged my '98 R1100RT 75th Anniversary edition out into the daylight after a 12 year slumber in my garage.

 

The battery had died, it lasted a few years on a battery trickle charger but I guess that's not unreasonable.

 

I wheeled the bike to a local mechanic with a view to getting it running so that I can get it road legal again.

 

He's replaced the battery, cleaned out the tank and after a bit of fettling has got the old girl back up and running. Sounds awesome with the Remus exhaust.

 

I've just been to visit him and noticed something - when the ignition is on the fuel pump runs continuously - I'm sure I remember it only running for a second or so and if the start button isn't pressed the pump stops.

 

Am I mistaken or is there something not right? Is there a fuel pressure switch that cuts the pump or something similar?

 

Thanks for any insight you can give.

 

.

[Michaelr11]

Can't say why, but you are correct.  When you key the ignition ON, the Motronic (ECU) should run the pump for only a second or two and then it should shut off.

[dirtrider]

22 minutes ago, FlatBow said:

Hi, I have dragged my '98 R1100RT 75th Anniversary edition out into the daylight after a 12 year slumber in my garage.

 

The battery had died, it lasted a few years on a battery trickle charger but I guess that's not unreasonable.

 

I wheeled the bike to a local mechanic with a view to getting it running so that I can get it road legal again.

 

He's replaced the battery, cleaned out the tank and after a bit of fettling has got the old girl back up and running. Sounds awesome with the Remus exhaust.

 

I've just been to visit him and noticed something - when the ignition is on the fuel pump runs continuously - I'm sure I remember it only running for a second or so and if the start button isn't pressed the pump stops.

 

Am I mistaken or is there something not right? Is there a fuel pressure switch that cuts the pump or something similar?

 

Thanks for any insight you can give.

 

.

Evening  FlatBow

 

Are you sure it is the fuel pump running? If it actually is then it should not do that as it should only run for a couple of seconds at key-on, then turn off until the engine is actually cranking.

 

I have a seen a couple 1100 bikes run the pump for longer or erratically & that is usually caused by the HES acting up.    

 

If the HES wiring pigtail wires are cross talking (due to cracked insulation or being wet) then the Motronic could see that as a running engine signal & continue running the fuel pump. 

 

It's a pain but you might unplug your HES (Hall Effect Sensor) then see if the pump goes back to only running for a couple of seconds at key-on. If it goes back to normal then you need a new HES (or your HES rewired) as it is about to fail & leave you stranded. 

 

You might also talk to you mechanic that worked on it & ask if he by-passed the Motronic controlled fuel pump circuit  with a direct ignition-switch-on 12v power to the pump. I have also seen this done, usually by someone that doesn't understand the electronic fuel pump control circuitry, so they just wire it to run the pump all the time with the key-on. 

[FlatBow]

Gents/Ladies,

 

Just an update:

 

Firstly thanks @Michaelr11 and @dirtrider for your replies.

 

The issue of the pump continuing to run has changed to an intermittent issue.

 

I've only ridden it about 10 miles with a few stops and restarts and the pump behaves itself (stops after a couple of seconds on ignition on) about 50% of the time, otherwise it just continues to run. I decided to leave it as perhaps it just needs some use.

 

I took the bike for it's MOT and it sailed through with an advisory about the brakes dragging slightly - not bad having been standing since 2009.

 

I'll be contacting the DVLA to put the original reg plate back on it (New car coming that I fancy having my private plate on) and then putting the bike up for sale.

 

 

[dirtrider]

3 hours ago, FlatBow said:

Gents/Ladies,

 

Just an update:

 

Firstly thanks @Michaelr11 and @dirtrider for your replies.

 

The issue of the pump continuing to run has changed to an intermittent issue.

 

I've only ridden it about 10 miles with a few stops and restarts and the pump behaves itself (stops after a couple of seconds on ignition on) about 50% of the time, otherwise it just continues to run. I decided to leave it as perhaps it just needs some use.

 

I took the bike for it's MOT and it sailed through with an advisory about the brakes dragging slightly - not bad having been standing since 2009.

 

I'll be contacting the DVLA to put the original reg plate back on it (New car coming that I fancy having my private plate on) and then putting the bike up for sale.

 

 

Morning  FlatBow

 

As long as the pump doesn't stay running after the key is turned off then not a big deal if is runs all the time as the pump runs all the time the engine is running.

 

There is a safety factor in that the pump should quit after a crash but most I have seen the engine usually stays running even with the motorcycle on it's side so even that part isn't that important.