replaced fuel pump and no pressure

[Elutheros]

87 Bronco II, with new tank, intank pump, filters, and I just replaced the high pressure pump after some poor running issues and tester showed just 20 PSI. Now, I just installed the new main pump and can't get any fuel pressure at the injector rail. Pumps both run when key is turned on and when cranking. Fuel line to the new pump has fuel in it (tank is full). No kinked lines and I did not change anything else. removed filter and blew low pressure air through both ends---no blockage. Thought I might have stupidly put the pump in backwards, but every diagram I can find shows the electrical connectors facing towwards the front of the vehicle and that's how I've got it mounted.

I'm concerned I will damage the new pump if I keep cycling it and it has no fuel in it. It did get warm after multiple on/off attempts to get it started.

What am I missing?

[BLUTHUNDER1]

Check your fuel pressure regulator

[BRUTUS_T_HOG]

The frame rail mounted pump is what builds the high pressure to the fuel rail, the in tank pump is just to supply the main pump from the tank. I would be looking into the frame rail pump having failed. Are you getting full battery voltage to both pumps and have good ground at both pumps?

[Elutheros]

FPR is new also. As I said, I just installed the new rail mounted pump and it runs but is not producing pressure at the injector rail. Before I replaced the pump, I checked the voltage and it was good.

[dave2575]

Check the fuel pump inertia switch.

[BRUTUS_T_HOG]

Well if the pump runs and you have no pressure and no blockage. Defective pump

[yodaman1151]

I had my hpp in backwards and it did the same thing.

[Elutheros]

Replaced the FP relay and still no pressure from the new pump, so I got frustrated and put the old pump back in just to see if I could get what I had before--started right up. In the middle of the swap, I had the fuel line hanging over a bucket to catch the fuel siphoning from the tank (the very full tank). After that bucket sat for a while, I had a distinct separation of the fuel from what I guess was water??? Wierd, since all the replacement of parts took place in a short period of time and the tank being brand new didn't have time to accumulate that much moisture.

Anyway, it runs with the old pump--and it is running well. Go figure. I don't have the pressure guage handy to check the fuel pressure, but I'm just happy it is driveable.
Must have received a bad pump from Rock Auto.

[freedom5]

Originally Posted by Elutheros

Replaced the FP relay and still no pressure from the new pump, so I got frustrated and put the old pump back in just to see if I could get what I had before--started right up. In the middle of the swap, I had the fuel line hanging over a bucket to catch the fuel siphoning from the tank (the very full tank). After that bucket sat for a while, I had a distinct separation of the fuel from what I guess was water??? Wierd, since all the replacement of parts took place in a short period of time and the tank being brand new didn't have time to accumulate that much moisture.

Anyway, it runs with the old pump--and it is running well. Go figure. I don't have the pressure guage handy to check the fuel pressure, but I'm just happy it is driveable.
Must have received a bad pump from Rock Auto.

Glad you got it running again. Faulty parts seem to be pretty common these days. A lot of them come from Mexico. I went through two Master cylinders before I got one that seems to be OK. As for the possible water - you could have got some bad gas when you filled the new tank - especially if you have had some recent heavy rains in your area. Dump a couple of cans of Gasoline anti-icing fluid in the tank. It will mix with the water and let it burn through. 100 proof alcohol will do the same.