Pathetic Fuel Pump?

[jambon]

Looking at my fuel filters, one's full of fuel and the other is almost empty, and I'm thinking this could be why the bikes quite temperamental.
The filter for the petrol tank is full, but the filter from the fuel pump looks very low. The fuel pump is dribbling fuel into the filter at a very slow rate when running.

Is this normal, or should the pump, as I suspect be 'pumping' fuel at a steady rate into the filter?

Thanks in advance

[Ewetea]

Please go to page 2 of this section, and about 8 threads down, you should find a thread that I started regarding the fuel pump on Sat Jan 14. I was also concerned that the filter did not seem to be full, and thought that an "air lock" could cause problems. But it doesn't matter, and in fact must be quite normal. When the starter button is depressed, 12V is applied to the pump, which operates it flat out, to ensure that the carbs are quickly filled (maybe the bike hasn't been used for a couple of weeks and fuel has evaporated). Once the engine is running, the pump only requires occasional voltage to "top up" the carbs. Just use a long screwdriver to listen to the "clicking" of the fuel pump and you should be reassured that everything is OK.

[jambon]

Ewetea, firstly thanks for sparing me a flaming for not seeing your thread, funny as I've looked through all the pages more than once.

Your thread is obviously well informed and there's a few key facts identified which really helps. I'm sure when my starter button is pressed the fuel pump doesn't 'pump', but instead trickles/spits just like after the bike has been started. I can confirm this tomorrow for my own piece of mind, but it might explain why it's reluctant to start. I've got a working fuel pump coming in the post, so will be able to see if that does in fact change anything.

Will see how I get on, and thanks again for pointing out your thread.

[banner001]

could be that your carbs are already fairly full, it cant work against a pressure gradient.

disconnect the fuel line, put that end in a bucket and hit the starter button and see how much comes out then.

[jambon]

Good call banner.

Scenario one: Start bike up and watch/listen to the fuel pump.
- You can hear the pump clicking away when the start button is pressed, but only a trickle of fuel is coming through, certainly not a large amount.

Scenario two: Disconnect the hose from the pump into a bucket to see if a pressure gradient was stopping it.
- Exactly the same with it being only a trickle of fuel coming out.

I'll soon tell when the new pump turns up, but it's good to eliminate the pressure gradient cause.

Thanks guys

[jambon]

New pump installed, and initially I thought it had made a difference. Tried starting this morning and the usual story, it wouldn't start.

Tried the fuel line into a bucket trick with the new pump, and same thing, the pump's pretty weak.
Tested the starter relay with a multimeter like in the manual and couldn't pick up a reading. When the starter is pressed though, I can pick up 11v from the black/blue wire on the loom to the starter relay, which I think is normal from looking at Ewetea's thread.

The bike takes about 2 minutes with the choke/starter to get any sign of life, once it's been started and warmed up it's happy to start on the button but not necessarily stay running for long. I'm reluctant to keep using the choke as it has smoked from the radiator area a couple of times when over used. Once it has warmed up and you give it some throttle, the revs are very sticky and seem to stick/climb on their own.

After not getting a reading from the pump relay I tried my own fuel pump with a bottle, and even then it did struggle. I'm getting a bit clueless as before the winter it didn't have any of these problems and I've replaced changed quite a few things. When I refitted the carbs I also set the pilot screws to what the manual says so it can't be that.

VIDEO BELOW

http://vimeo.com/62166497