Both fuel pumps loud after replacement

[paulmess]

Hello,

I have an 86 with 99,500 miles. The inline pump was buzzing very loudly so I went ahead and replaced both pumps and the fuel filter. Now both new pumps are buzzing very loudly!

I feel as if there is a blockage, the fuel lines look good (no bends or obvious damage). The gas tank is full.

What are some of the possible issues and what should I check first? The vehicle runs strong, doesn't hesitate or anything, but the pumps are both loud enough that I'm certain something is wrong.

Thank you for the help

[jlevie]

Were these OE or non-OE parts? That can matter.

You could have an obstruction in either the supply or return lines, a bad filter, a bad FPR, or rust sediment in the tank. If the pumps are loud when the car is started and stationary, sediment in the tank isn't the issue. But if quiet when first started and gets loud while driving the tank could be the problem.

[paulmess]

Were these OE or non-OE parts? That can matter.

You could have an obstruction in either the supply or return lines, a bad filter, a bad FPR, or rust sediment in the tank. If the pumps are loud when the car is started and stationary, sediment in the tank isn't the issue. But if quiet when first started and gets loud while driving the tank could be the problem.

It's loud even when first started and stationary.

New thought, could the fuel dampers near the inline pump get clogged? It seems as if the inline pump has a little shake to it like it's struggling to push through the damper.

[jlevie]

The damper is a possibility. Iy can be deleted.

Were these OE or non-OE parts? That can matter.