Yamaha R6 Forum: YZF-R6 Forums banner
1 - 4 of 4 Posts

· Registered
40 Posts
Discussion Starter · #1 ·
05 R6

Hey guys... When you guys take off the fuel tank does all the gas leak out when you take out the main fuel line or does the gas stay in from the pressure of the pump?

I have an 05 r6 that I rebuilt. After I put everything back together I noticed that the bike starts for a half second and then dies. Tried giving it gas and starting, still the same issue. If i turn the ignition off an on a few time to prime the engine I have better luck but the engine still dies after a second. So I assume the engine is not getting enough fuel? I wanted to take the fuel tank off to inspect the fuel pump so when I unconnected the main fuel line gas starting coming out in a stream.

From what I recall when you unhook the line the suction from the fuel pump keeps the fuel inside? I haven't taken the tank off too many times so i don't remember if this has happened before or the pump is just crapping out. Just for fun I filled the tank up, attached a tube to where the main line goes into and dumped the fuel to a container. I turned the ignition on to see if the fuel pump activates and sure enough fuel sprays out. I read in the manual that the fuel pump needs to put out high PSI for the throttle body to work correctly. Maybe I'm not getting enough pressure which is why it's not starting? I ordered a used fuel pump from ebay but wanted to ask if anyone else has had this issue.

· "The Dude abides .. "
4,695 Posts
fuel should not pour out if the ignition is off. Per the manual, doing what you were doing is a method for testing the pump (hooking a hose to the pump and turning on ignition). Fuel should shoot out in a stream for a few seconds. 47psi is spec for a 2006+ fuel pump, and suspect it's the same/close for a 2nd gen bike.

having a spare pump isn't a bad idea. Usually when fuel is pouring out, you had the pump apart and didn't seat the thick o-ring in the nozels that join the 2 plastic halves together. Even a few psi low will cause a bike to run like crap, or not run at all. For every 1 psi drop in fuel pressure, you are getting less fuel flow through the injectors. This is also why it's critical all the injectors flow very close to same amounts of fuel..
1 - 4 of 4 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.