Hello, I have a problem with the f3 from 97. I start the engine, the pump sends fuel to the carburetor, I leave it at idle and it runs out of fuel, and the pump only starts after I start the motorcycle again. Do you have any ideas?

[img]data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABQAAAAUCAQAAAA ngNWGAAABDUlEQVR4AYXRgUZDYRjH4TegFTKgpEqiFJgoWAoME QGBgBboChaaAKxLKAhAhQqAdAmpBIQolkCFqp2nITvNKXuA7+/Hhzey5OWjE4Nq3rzY1f9/NGHPB549492+8Ww060iCS2XdctZdI3GsECmb+HJoIX6x6EgDm+ lURTH+YB7V9nAqE5WNme4YKuOiY6iMe6PaQxUUIuTbswgFVNJw A8sO3Bn6yR6bWZMSNtJwDtuWfHpQxaPx9C9zadil7jrCigbq6U XceNIVKTWUIqypm2ytJdTiNyNeXclF6GttOVfeDEc7qzjR23r3 OMFqZKng1kw0mXGLrfibHTScOZWgGv9TdC6ROFeMTgwYiIxvJz MRWQbeGZUAAAAASUVORK5CYII=[/img]

 

I don’t understand. The pump runs out of fuel? That would be no fuel to the pump. The pump stops pumping fuel that would be the fuel pump. Caltric sells a fuel pump for $19 and works great.

 

That is correct behavior. Pump only runs until float-bowls are filled, then stops. Pump relay is triggered by ignition-pulses from ignitor. So it only runs pump when engine is spinning.

Test and measure trigger wire between ignitor and pump relay to ensure it’s not broken.

 

what color is that wire? black and yellow ?

 

Here’s how fuel pump relay is wired:

blk/wht = battery power +13v full-time when key ON
blu/yel = grounding pulses from ICM (shared with ignition coil 2-3)
blk/blu = power pulses to fuel-pump

The grounding pulses from ICM would measure full-power most of time. With short pulses to ground to trigger ignition-coil and fuel-pump relay. Looks like this on oscilloscope.



Can also use solenoid-light to check for pulses. And on fuel-pump relay output to pump as well.

 

So i need to track blu/yel = grounding pulses from ICM (shared with ignition coil 2-3)

 

i check all wire from relay and it s all ok...

 

Yeah, start with that wire from ICM.
Make sure it reaches coil
Along way it splits off to fuel-pump relay.

Measure its resistance end-to-end between ICM and pump relay to make sure it’s not broken.

Verify pulse signal at fuel pump trigger input and output. Pulse signal to pump may be large enough to pick up with LED test-light. Use solenoid test-light to be sure.