EFI fuel plumbing

[bojen]

Could someone explain the tube going across the fuel rail and the return line??? It makes no sense to me??? Is it some kind of overflow bypass or…..??? <?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>

[Carter Powell]

What that little line is that is crossing over from the fuel rail to the return line is a brass tee with a little tiny hole in it thats so small that it will not effect the fuel pressure while the motor is running, but it will allow the fuel pressure to bleed off when the motor is turned off. This will keep a leaky injector from causing you great pain and possible flooding as well. A lot of the early 2.4 motors did not have this little tee and the bypass hose going back to the return line and you had a lot of pressure in the fuel rail even after the motor was shut off. It is just a safety valve that turns off the high pressure after shutting down the motor.

Best wishes, Carter Powell

[bojen]

Tanks for quick reply! I kind of suspected that (but was far from sure). I just got the merc 2,5 here in <?xml:namespace prefix = st1 ns = "urn:schemas-microsoft-comffice:smarttags" /><st1:country-region w:st="on"><st1lace w:st="on">Sweden</st1lace></st1:country-region> and it has been run on a offshore cat argo 24. I got everything but the fuel pumps with the motor. In the process of figuring out what pressures and pumps to use, I saw that weird tube and started to scratch my already overworked head. I did not want <st1:PersonName w:st="on" ProductID="to take the">to take the</st1:PersonName> assembly apart due to the hoses being a little bit dried up. Season is short in <st1:country-region w:st="on"><st1lace w:st="on">Sweden</st1lace></st1:country-region>, and I want to do a few test runs before I get new hoses and so……..<?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o></o>
<o></o>
Once again Thanks!<o></o>
<o></o>
/Bojen <o></o>

[pyro]

You should replace those hoses anyway, just use real EFI hose clamps instead of those slotted strap clamps when you re-assemble.