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Discussion Starter #1
Ok I installed my new FASS 150 lift pump in the LLY and put in a sinister diesel sump kit at the same time. I followed the directions on both as well as a couple videos I watched. Everything went together nice and I let it sit over night with a full tank to ensure no leaks.

Started it up and it all sounded good, slight hum like a normal fuel pump up close but nothing I would cal loud. Drove it about 50 miles that day then it sat for two days. Went to start it up and it’s making a nasty grinding type sound which, from what I can read is a cavitation type sound. If I loosen the water filter screw while running the sound goes away then after awhile it will come back. All the lines are tight, I primed the fuel filter by loosening it, running it till gas came out then tightening up the filter, I even cracked the bleeder valve and completely covered myself and engine bay with gas haha. Still making this noise.



Here’s two videos I made



 

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Sorry I hate threads with now updates. I thought I got this but looks like I didn’t.
I ended up pulling the sump back off and found this rubber cap of some sort No idea what it is for or how it got there but my only explanation is this was being pulled into the sump and blocking the outlet which feeds the lift pump. This would cause the lift pump to work harder and struggle to get fuel.
Put it all back over her and everything is all good for a few hundred miles now.
FD6D385B-5F69-4D33-B48F-9F25E2EC007A.jpeg A50A672E-12C2-47F0-A786-660D5BDED473.jpeg
 

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Thanks for the update similar things have happened before.
 
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