matego

I installed a Walbro lift pump about 2 weeks ago. I did not notice it at first, but during the past week, I noticed a slight whining between 900-1300 rpm coming from the engine. I pulled the belt and ran it to see if it went away, and it didn't. I switched to the stock l/p and it went away. I had the Walbro set to 26 psi at idle, is that the problem? I already ordered a spring and shim kit for my relief valve to try and lower it a bit. Is it normal to hear a slight whine? It is extremely faint and you have to have the window down to hear it. Thanks for the responses!!

Rpainter

I get a whine I finally found it the whine was comming from the bypass itself where is your bypass located??

matego

My bypass is along the frame, mounted near the middle of the back door. I listened around the pump area and all I could hear was the walbro running. Is yours loud at idle, when it is returning the most fuel?