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mercrazy
09-16-2008, 09:17 AM
on my 260, when i turn the key off, the pressure drops quickly to about 12 lbs. and then slowly drops to 0 in about 15 minutes. is this normal? my engine is flooded on a warm start. could this indicate a leaking injector? the enrichment wire is disconnected. i've checked all electronics and vacuum fittings.
JASON ALLEN
09-16-2008, 09:35 AM
That is normal for the pressure to bleed down.
STV_Keith
09-16-2008, 10:19 AM
There is a bleed orifice between the fuel rail and the return line. It's a small hole and allows for the pressure to bleed off once the pump stops. The orifice is very small, so doesn't effect anything when running and constant pressure is present.

When I turn the key off on my rig, the fuel pressure drops at basically the same rate down to around 10psi, then slower to 0. Sounds like yours is about right. Probably takes 5-7 seconds to go from 40-10psi?
mercrazy
09-16-2008, 10:40 AM
thanks guys. i've fought this problem all summer and i'm running out of ideas.
bill mason
09-17-2008, 06:31 AM
like the man said "there is a small brass fitting that goes between the bottom fuel line from the regulator and the return hose. Take it off and try to blow thru it. Betcha anything it is plugged up. Been there done that way to many times and it will cause the engine to flood. Just soak it in Sea Foam for 15 minutes and blow compressed air through it. Walla it is open and she will start so much better. My tow cents
malexie
09-25-2008, 11:14 AM
There is a bleed orifice between the fuel rail and the return line. It's a small hole and allows for the pressure to bleed off once the pump stops. The orifice is very small, so doesn't effect anything when running and constant pressure is present.



How small of a hole is the orifice?
Jay Smith
09-25-2008, 12:35 PM
about .010" ish Oh and Forget drilling it unless you have a set of Micro Mini drill bits, I have a set that you have to have a magnifing glass to seewhat end is the drill and I use a special set of pin vises. Use the soak and air method if you drill the hole too big the bleed rate will rob the fuel rail and the motor will run lean....

Been there and done it !
Jay