leon

Minimum pressure is 15psi at 2000rpm. Unless something is is stuck in the restrictor fitting or return line, you won't get the pressure without the correct flow.

thank you , recall there is a minimum flow also, on return line if you have that info .

thanks leon

Hi Team,
my old 71 Series Workshop Manual, Troubleshooting Section, tells us that the fuel return line flow rate should be approx. one half of a gallon per minute at 1200 RPM.
If flow is low check:-
1/ fuel strainer.
2/ fuel filter.
3/ individual injector fuel filters.
4/obstruction in the fuel lines--supply and return.

Fuel Transfer pump for wear to gears, housing, etc.
Check if the restrictive fitting is missing or been replaced with an incorrect fitting in the fuel manifold--I guess they are saying that this fitting is on the fuel return side of the system as the chart is not very explanatory--been too long since I worked on these to recall now-- but it would be the obvious place for it to be--I stand to be corrected.
Swollen old hoses can restrict fuel flow too, or even ones with the inner membrane torn during careless fitting, and closed over at a fitting/steel line.

Hope this helps.
Cheers,
Eddie B.

[quote="edb"]Hi Team,
my old 71 Series Workshop Manual, Troubleshooting Section, tells us that the fuel return line flow rate should be approx. one half of a gallon per minute at 1200 RPM.
If flow is low check:-
1/ fuel strainer.
2/ fuel filter.
3/ individual injector fuel filters.
4/obstruction in the fuel lines--supply and return.

Fuel Transfer pump for wear to gears, housing, etc.
Check if the restrictive fitting is missing or been replaced with an incorrect fitting in the fuel manifold--I guess they are saying that this fitting is on the fuel return side of the system as the chart is not very explanatory--been too long since I worked on these to recall now-- but it would be the obvious place for it to be--I stand to be corrected.
Swollen old hoses can restrict fuel flow too, or even ones with the inner membrane torn during careless fitting, and closed over at a fitting/steel line.

Hope this helps.
Cheers,
Eddie B.[/quote]

The return restrictor fitting is normally screwed into the head with the return line coming off of it.

There are no pressure specs on fuel return line, have to know which engine you have for fuel pressure and return fuel spill.
Bob