Mallory 4309 Regulator question. - Third Generation F-Body Message Boards

zacharyhorn · 09-23-2009, 02:04 PM

Replacing the stock fuel pump with the Walbro 255 and forgot to check on how the fuel pressure changes up or down. When you spin the nut clockwise does it lower the pressure or raise the pressure. I just don't want to blow any of the seals on the carb before I try the new pump. I should've checked this before hand but just forgot.

Thanks,

Christal_Z28 · 09-23-2009, 02:12 PM

Spin to the left (counter clockwise), drops fuel pressure.

Spin to the right (clockwise), it raises the fuel pressure.

zacharyhorn · 09-23-2009, 02:15 PM

Quote:

Originally Posted by Christal_Z28

Spin to the left (counter clockwise), drops fuel pressure.

Spin to the right (clockwise), it raises the fuel pressure.

Thanks for the quick reply.

1ADan · 09-25-2009, 08:28 AM

If you've got the fuel system cracked open to do the pump, why not toss an inexpensive pressure guage on one of the open port on the FPR? Summit makes a liquid filled guage that's perfect for (permanent) underhood readings.