Should a new fuel pump sound like a food processer?

[crazyplowboy]

I just put a new fuel pump in my truck this evening, and when I turned the switch to see if it was working I heard a sound like a food processer chopping up a pine tree coming from the fuel tank. It makes a grinding sound , but every once in a while the grinding sound will go away and it will be a pleasent hum for a few seconds, then the loudness returns. It seems to have mellowed out a little as it has ran but still makes a grinding sound. have you guys ever heard of this?

 

[m16ty]

Could it be air in the system that hasn't worked it's way out yet?

 

[crazyplowboy]

I'm trying to bleed the air from the system, I did a filter change on new years eve which led me to find out that my pump was dead. Got a new pump put it in and thats where I am now. The pump is flowing fuel pretty well. I took the screw out of the top of the pump access panel and it flowed like crazy. I ran the pump for probibly 1-2 minutes total, but the sound just makes me nervous.

 

[rockman]

Should be a pleasant hum that you can hear when you flip up on the accessory switch. like a larger electric fuel pump.Bill

 

[crazyplowboy]

I just took it out again and looked it over well. The bottom plate that covers the impeller was not seated fully in the recess, so I pressed it in and tightened up the screw. Then I noticed that the hose was too long and was pushing down on the pump outlet causing the pumping section to be pushed away from the motor. I shortened up the hose and thigtened up the 4 screws holding the bottom section to the motor. I tried the motor out of the tank and it worked perfectly (no terrible noise) so I put it back in the tank and it started making noise again.

 

[crazyplowboy]

With the bottom plate off I can move the impeller up and down probibly .100 in. should there be that much play in it? I noticed when I hooked it to power I could see the impeller drop down and hit the bottom plate for a second at start up and shutdown, during this time the pump made the sound. It's about ten degrees here right now so maybe the fuel is thickened up enough that the magnets are not strong enough to spin the impeller allowing it to drop down.

 

[jim-m35a2]

Take it back and get another pump.
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LovelyWendie