Is my bike being fuelish?

[sunnybrook]

It seems there are 20 pages of threads about "fuel" for the AT, and a lot of them also mention the word "pump".

At the weekend having filled the tank, I did a fairly reliable 50 miles on my bike. I had an unscheduled breakdown on the dual carriageway at 55mph when the engine revs suddenly dropped away to nothing and I was left coasting onto the hard shoulder. Grabbing the throttle didn't make any difference. Once stopped for a minute or two and not seeing anything wrong, the bike fired up ok and I carried on with no further problems.

Today I was all ready to ride to work, bike idling on a bit of choke. For two or three minutes it sounded ok, with an occasional pop from the exhaust ... and then the revs dropped to nothing and the engine shut down. So I attended to the bike, with the starter motor doing its best but I couldn't get the engine to fire for a dozen attempts with and without choke. Eventually the thing got going at a very reluctant 1000rpm or so, but as soon as I looked at the throttle, the engine died. It did that two or three times, by which time I was afraid of flattening the battery (again) and I was sufficiently hot and bothered by then that I heaved the bike back into the garage, threw my armour into the house and cycled to work as usual.

Considering that I put down a healthy bundle of wedge for the machine and I've only managed one day's riding on my bike so far, I'm a bit annoyed. I get the impression that the engine was only firing up on the limited amount of fuel held in the carbs, and there was nothing in the fuel line for it to rev with.

Fuel pump? Fuel filter? Choke cables and plungers and springs? Fuel vaporisation?

Oh yes, and my Scottoiler isn't delivering fluid, so if you can fix that too, that'd be great.

[Radio-active]

Well its not the Choke.....it wouldn't die at speed....it might misfire...and at idle its lumpy......

Its not crud in one carb because it doesn't go down to a 324cc single!...

Its not leads, spark plugs or coil pack for the same reason....

Its probably fuel pump....although I havn't experienced this.....yet!....especially as it happened when the tank got down to a lower level...there are loads of fuel pump related articles on here....someone on here is about to confirm this is probably your problem!!!!
.....and you can buy a new pump from the forum shop....and its probably worth replacing the filter at the same time....

Alternatively its ECU or wiring related...tested by taking a plug out, resting on the head and seeing if there is a strong spark...but I would be really suprised if this was the case...

If the bike is new to you...it could be worth checking the plugs anyway (on both cylinders) to check if the plugs are black and sooty....a sign of a sticking choke...the bike will run fine if its only slightly 'on' but will waste fuel....

The Scottoiler....put it on 'prime'...and squeeze more 'scottoil' oil in....untill it comes out the chain end!....and check the vacuum pipe is attached at the Carb end and attached at the oiler end once you have filled it up....

Hope this helps....

[TanisWolfbane]

Sounds like fuel pump to me, mine went after repeatedly hitting reserve (it doesn't seem to like sucking when there is only air in the fuel line)

It's really easy to test, just unplug the fuel line from the out of the pump if nothing is coming out then plug it back in and unplug the in. If nothing is still coming out unplug the in to the fuel filter.

I.e work your way back from the engine, where ever the fuel stops thats your problem!

For a temporary bodge either bypass the fuel pump and make sure you keep her filled up so gravity can do the work or crack open the fuel pump and use a nail file to separate the burnt contacts.

Another sign that its the fuel pump will be that she is very hot to the touch.

[sunnybrook]

...or crack open the fuel pump and use a nail file to separate the burnt contacts.

Now that's my sort of DIY.

I've not had the bike that long, and it's due a service fairly soon anyway (odo says 14200 miles). I'm thinking about an oil, oil filter and air filter change, so it might be worth changing the fuel filter too while I'm at it.

[francis_geoff]

If you can start the engine, fire it up and feel fuel pump - it will "tick" about every 5 seconds. If not ticking - remove clean points as mentioned and it will probably work. The pumps do not like running dry, and if due to fail will do so within a few days of running out of fuel.
If you run out of fuel and then fill tank, the fuel pump will sound like "big end" knock - a bit scary

[sunnybrook]

If you can start the engine, fire it up and feel fuel pump - it will "tick" about every 5 seconds.

That's the problem - I can't get the engine running for long enough to inspect the pump. Would it be possible to disconnect the starter motor lead and the fuel line into the carbs, then go for ignition and see if the pump squirts fuel into a jug? Or is that incredibly dangerous?

I'm fine bending bits of metal and cutting screw threads and all the mechanical stuff, but my brain turns to swiss cheese when I start trying to follow wiring looms or adjusting petrol/air mixtures.

[TanisWolfbane]

You don't need the engine to work for the fuel pump to work, you just need electricity! Just disconnect the out from the fuel pump and try starting it. It's literally that simple.

[Mutley]

If you're not sure if the pump is working and have tried holding it whilst turning the engine over, look for petrol coming out of the fuel pump.

If you look under the left hand edge of the frame as if you're sat on the bike. From this side, you can see the black pipe running from the right hand side of the petrol pump up and under the frame where it leads to the carbs.

Gently push the pipe away from you & it'll come away from the frame at the connector. Pull the clip off & separate the the fuel line from it's connector. You can then direct the petrol into a jug to measure how much is being pumped out. Should be a minimum of 900cc per minute. Cheapest way is to do it for 5 seconds and multiply X 12

If you've got steady hands, the cleaning of the points in the end of the pump is a good idea. Mine ran for ages after cleaning.

[hans motors]

Hi
If it is found that the fuel pump is at fault we do the German Pierburg fuel pump that is a direct replacement see previous posts http://www.xrv.org.uk/forums/showthread.php?t=9186
We have them on the shelf @ £55.00 each plus vat and carriage (UK mainland only) @ £5.00.
Our internal part number for the pump is PP20001.
Please do not hesitate to contact me on 0121 749 8820, e-mail lloyd@hansmotors.co.uk or see our web site www.hansmotors.co.uk if you need more information.
ps
The original thread goes back to 2005 hence the differnet pricing and carriage free minimums.

[Lord Vader]

Hi
If it is found that the fuel pump is at fault we do the German Pierburg fuel pump that is a direct replacement see previous posts http://www.xrv.org.uk/forums/showthread.php?t=9186
We have them on the shelf @ £55.00 each plus vat and carriage (UK mainland only) @ £5.00.
Our internal part number for the pump is PP20001.
Please do not hesitate to contact me on 0121 749 8820, e-mail lloyd@hansmotors.co.uk or see our web site www.hansmotors.co.uk if you need more information.
ps
The original thread goes back to 2005 hence the differnet pricing and carriage free minimums.

Yep and we sell the Facet Fuel pump on this site for £41 plus £3.75 postage
just have a look here
http://www.ruggedroads.com/shop/cate...am=cid%3D61%26