Printable Version of Topic

Posted by: gunny Nov 5 2012, 08:04 PM

When do you measure the fuel pressure? I get 29 lbs when I turn on the key and 32 lbs when it's running.
1976 2.0 DJet

Posted by: ConeDodger Nov 5 2012, 08:06 PM

I think that's spec... You measure running.

Posted by: Dave_Darling Nov 5 2012, 09:52 PM

Measure running; 29-30 is the spec. At 32 PSI, you'll be a little richer than at spec. If that's working for you, then good enough.

--DD

Posted by: walterolin Nov 5 2012, 11:08 PM

Difference is probably a function of the alternator running. Ignition on, but no alternator, you are drawing on the battery, and any load will drop the voltage a little. With the engine running you are probably getting a robust 13.5 volts into the system.

Posted by: ConeDodger Nov 6 2012, 01:34 AM

QUOTE(walterolin @ Nov 5 2012, 09:08 PM)

Posted by: walterolin Nov 6 2012, 06:59 AM

I was thinking (?) fuel pump is an electrical device, subject to variations in the voltage, but forgot there is a pressure regulator in the line. On the other hand, if the regulator is a really precision device, it shouldn't matter what the pump is doing. Perhaps the fuel flow in the dynamic state causes the small drop.

Back to sleep.

Posted by: gunny Nov 6 2012, 08:21 AM

I guess I will need to reduce to 30 while running.