Jakesnk
I have seen this issue before on various other C-130's. All models here in the states and while deployed. Here are a couple of quick things you can have done or do to help narrow down the troubleshooting parameters.
1). While the aux pump fuel pump is running open the center separation valve and then depress the crossfeed primer button and see what the pressure drops down to. Kill that pump and turn on the opposite side aux pump that you have no issues with and hit the crossfeed primer button and compare these pressure readings. Let us know what the pressure differences are if any.
2). Pull the aux tank sight gage for the aux tank with the questionable pump. Youll see two black hoses coming from the aux pump thats on the door, one large and one small. The large hose is the aux pump discharge hose, make sure this hose at the top where it arcs over to the wall connection is not crimped or bent in a way that restricts more the approx. 40% of the hose diameter. NOTE: Ive seen these hoses restricted enough to cause demand feed issues.
3). If possible see if the pump is made by a company called "ROMEC". The name should be on the silver and red serial plate. Romec pumps have a design issue that occasionaly causes low readings during high demand situations.
Ill stop for now until I hear anything back from you because there are a number of other things that can cause this problem.
Good luck
Moon
