Fuel Pump continually priming

AndyJW

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I've just fitted a set of chrome plated quick disconnect. Now when I turn the ignition on the fuel pump continually primes when before it used to shut off after a couple of seconds. Also, the bike won't start. I fitted the disconnects opposite ways round since they fitted in the space better that way, assuming that it didn't matter and that fuel would flow regardless. I am now thinking that it does matter, but don't know which way round to change them - should it be male or female coming from the tank or maybe if one line is the feed from the pump and the other a return then maybe they do need to be different, but opposite to the way I've got them.
Before I explore every permutation of pipes/direction of disconnects, has anyone else had this problem before? I am assuming that this is the problem and I'm not missing something else I could have done wrong.
 
I'm pretty sure I didn't get the two pipes mixed up since I was careful not to do that, but if that's what happens when you do connect them up wrongly, then I guess that's what I must have done - somehow.
 
Did you take the tank off to do the job?Sounds electrical rather than plumbing...multi connector?

I'm probably talking shite (but that is half the fun of this site remember )



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I'm pretty sure it's not electrical since pump is actually running ok, but doesn't stop as it should. Also, it's too much of a co-incidence that I've been altering the fuel lines and now I've got a fuelling problem - I'm thinking that the pump keeps running because the pressure isn't building up sufficiently for the injectors to be able to work. So either I've got the fuel lines mixed up or there is a blockage in the high pressure feed pipe.

So I can eliminate me having mixed the two pipes up, can someone please confirm that the high pressure feed (the front most pipe emerging out of the tank) goes to the lower of the three plastic pipes going into the plastic housing on the right of the bike - the middle one going to the right hand injector. I've checked some pics on the internet and I'm sure this is correct, but want to eliminate it for definite.
 
Just disconnect the lines and stick them in a jamjar and turn on the ignition will soon show you which one is the feed/pressure one.
Certainly sounds like you have them mixed up.
 
Andy, There's nothing you can do to the fuel lines that will make the pump run continuously. The pump is grounded on one lead and +12V is supplied from the fuel pump relay on the other lead.

The fuel pump relay requires that the key is on, and that the Motronic sends its coil a signal to energize the relay.

Remove the fuel pump relay and see if the pump stops, it should. If it does, put the pump relay back in and remove the Motronic relay, again it should stop.

Are you handy with a DVM?
 
Hi Roger,
Just tried what you suggested. Removed fuel pump relay and pump stopped, replaced and then removed motronic relay and again pump stopped. Yes, I am handy with a DVM.
Surely pump is not stopping because it is not getting up to sufficient pressure and that is why bike will not start - I don't understand how this can be an electrical problem, but am open to any ideas at the moment.
 
I would suggest that one of the fittings is not letting fuel through,

Either faulty fitting by mixing the fuel and return pipes,

Not pushing the fittings together far enough, they can be tight,

Or faulty fittings!
 
Hi Roger,
Just tried what you suggested. Removed fuel pump relay and pump stopped, replaced and then removed motronic relay and again pump stopped. Yes, I am handy with a DVM.
Surely pump is not stopping because it is not getting up to sufficient pressure and that is why bike will not start - I don't understand how this can be an electrical problem, but am open to any ideas at the moment.

Below is a link to a schematic. What is happening is that the Motronic is commanding your pump to stay on. There are a few possibilities:

A short in the wire from the Motronic to the pump relay, a failure inside the Motronic, or something wrong with the HES that leads the Motronic to believe that the engine is turning. You could try unplugging the HES connector which is located under the tank on the yoke above the alternator or unplug the Motronic and see if power stays on. If the Motronic is out but the pump runs then you have a short.

http://www.mac-pac.org/wp-content/uploads/2014/09/R1150RT-Electric-Diagram-V3_3.pdf
 
Andy, On a hunch you could try pulling fuse 5 for 10 minutes to reset the Motronic. Don't forget to relearn the throttle at some point.
 
Hi,

I haven't unplugged anything else lately. However I did disconnect and remove the battery overnight to give it a good charge up whilst I had the tank removed - presumably as far as the motronic is concerned this is as good as removing fuse 5. I have not however opened and closed the throttle with the ignition on for the motronic to re-learn whatever it re-learns when you do this - am off outside to try this now.
 
Pulling the battery does reset the Motronic. Since it's so easy to pull fuse 5 I'd try it. The relearn needs to be done but won't affect the pump.
 
One more idea. Maybe the most likely. If your fuel pump relay is sticky it might stay on once energized. Try swapping it with the horn relay.
 
Did you get an audible click when the connectors locked together? If not that is number one suspect. Put a smear of rubber grease on the o-rings so that they slide into place more readily.

I've always thought that there was a pressure switch in the 1150 pump so if it doesn't get up to pressure it doesn't switch off. Not certain on that though.
 


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