1150 fuel line change

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OK - so hoping that this doesn't turn into an epic like Fanums....

I'm pretty sure I'm doing something idiotic but thought I'd let you all have a good laugh before I figure it all out.

The story so far:

I recently had the internal pipe in the tank fail due to ballooning and eventual bursting so this was changed.

While removing the tank I noticed that a couple of my Quick Disconnects were old and worn so I decided to swap these for new ones.

So far so good.

I then noticed that the fuel line itself was looking a bit cracked so decided to treat myself to new fuel line. I have my fuel filter fitted externally so there's a fair bit of pipe on the outside of the bike.

Knowing my limitations I took each bit of fuel line off individually, cut a new bit and replaced it.

I then fired the bike up and it wasn't very happy coughed and spluttered and ran badly and cut out.

Hmm... maybe I'd overdone 'running the tank low' and had actually run out of fuel.

Put fuel in and now there is no coughing or spluttering or actual firing :(

I think the original firing must have been from remnant fuel in the filter and I must have done something wrong.

Sure enough there is no fuel pumping through the filter even when the bike is turning over although it does seem to get pressurised with air.

So I start to doubt myself.

Maybe I got the feed and return pipes the wrong way round :nenau so I swapped these over and no change :spitfire

I do have fuel coming from the tank but beyond that I think I must have got my pipes in a muddle :( :(

It has to be me being stupid - right? There's no way it's HES (changed about two months ago) or any other part failing is there?

All mockery and constructive suggestions welcomed :D

Thanks
 
Recheck your work

Bottom / forward hose is the pressure feed and should contain your filter
Top / aft hose Is the return.
Check your throttle cables seated correctly at TB.
Did you disconnect injector plug to give yourself room to work.
Is your fuel pump priming.
Use your old QR's to check for fuel from return circuit. If none try the pressure feed line.
 
Pull an injector, turn it over and if you have squirty fuel from the injector, your plumbing is OK.

Then you can start looking elsewhere :thumb2

PS the loop (180 degree) of tube inside the tank where the fuel filter used to sit inline can get kinked if you don't give it enough room to bend properly......you can slip a spring around it if you need to, or just add a few inches of length to that pipe so it bows rather than bends tightly.
 
<--- watching with interest as i've to swop to a different tank on the 'Special K'* soon and i'll have to swop tank internals over.
Maybe i can avoid wotever f*ck up you've made. :p

*yes - i know it's a completely different Bike.:pullface
 
Special Uncle Fil.......another thought for you......the fuel pump sock can collapse in on itself......it ought to have a steel coil in it to keep it 'inflated' but it's worth checking that it's not fubared and collapsed so there's not enough fuel under suction conditions, IYSWIM

:kissy2
 
PS the loop (180 degree) of tube inside the tank where the fuel filter used to sit inline can get kinked if you don't give it enough room to bend properly

Special Uncle Fil.......another thought for you......the fuel pump sock can collapse in on itself.....

Yeah but - internals of tank were working fine. Haven't touched them so 'should' still be OK.

Will double check which pipe I've connected to what.

I also have bodged (by someone else) electrical connectors - worth checking those?
 
Recheck your work

Bottom / forward hose is the pressure feed and should contain your filter
Top / aft hose Is the return.
Check your throttle cables seated correctly at TB.
Did you disconnect injector plug to give yourself room to work.
Is your fuel pump priming.
Use your old QR's to check for fuel from return circuit. If none try the pressure feed line.

OK so this is all good stuff and what I need to know :thumb2

So when you talk about 'top' and 'bottom' hose you mean the hard plastic pipes by the engine rather than the ones on the tank/fuel pump itself?

Throttle cables are one thing I do know to check so those are OK

No I didn't (intentionally) do anything to the injectors - worth taking them out and putting them back in just so I know they are OK? Do they just pull out or is there something more to it?

How do I check fuel pump priming? It makes a noise when ignition is turned on
 
As you look at the bike from the right, the top pipe also goes to the rear connection on the fuel tank plate. (fuel return)

The bottom pipe goes to the forward connection on the fuel tank plate (fuel pressure feed).

The priming is the pump running briefly when you switch on the ignition, if the motronic is enabled.
 
No I didn't (intentionally) do anything to the injectors - worth taking them out and putting them back in just so I know they are OK? Do they just pull out or is there something more to it?

If didn't disturb the injectors then it's unlikely your problem lies there. They are easy to get out undo the screw and they just pull out of the TB. They have an O ring at the bottom and the top. If you feel you need to remove the injector completely undo the clip to remove the injector from the fuel pipe.

When the pump primes, it provides a head of fuel pressure in the injector rail. Any over pressure fuel is returned to the tank. So if you disconnect the return line and connect up your Old QR you should get a burst of fuel come out each time the pump primes. If your getting no fuel. Then you could try the same at the fuel pressure QR. when the pump primes you should get a healthy squirt of fuel at about 40 psi. If nothing, then it could be you tank internals.

I wouldn't rule out the possibility that you may have a blockage in the hoses you replaced due to a foreign body. It's always a good idea to look or blow through a hose before it's fitted, lots of people don't.
 
OK so thanks to Ian I now know that my pipes are all connected correctly and that they aren't blocked as they've all been removed and checked.

Unfortunately I ran out of time this morning to check how far the fuel is getting but it definitely doesn't reach the (external) fuel filter which does definitely fill with pressurised air.

This is making me think tank internals must have somehow moved and the pump is sucking in air rather than fuel. The pump definitely makes its usual noise when ignition is turned on.
 
If you have replaced your QR's, are they the type with check valves in. I'm thinking you may have mixed check valve with non check valve and the valve is not opening allowing the fuel to flow. Particularly on the return line which could explain why you think the system is pressurised with air. This shouldn't happen, but not all QR's are the same. If you sourced them as a set (male & female) and replaced them as such they should be OK.

Try loosening one of your hose clips to see if you can get the fuel to flow. If tank has fuel in it then I can't see why you pump would pump air. It's submerged.

My guess if you malfunctioning QR on the return line.
 
Fuel

Make sure the q/r things are seated correctly and not still shut as they would be when released.
 
OK so it's fixed! :D

I had checked all external pipes were clear and QDs were all OK but wasn't getting any fuel from the feed line so this pointed to something internal.

Checked all internal pipes which were clear so it looked like the pump wasn't working.

Tested the pump which was working fine :nenau

Put internals back into tank and tested again - this time I had fuel coming out of feed when pump priming :nenau

Reconnected everything and all works fine.

Problem 'fixed' but I don't know what it was or why it now works. All connections were as they should have been and all pipes were clear and I had done nothing to the internals which had been working fine.

Go figure - but at least I can ride again.

Lesson learned - ..er.. none :D

Thanks to all who offered advice and reassurance as to what went where :thumb2
 


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