Check your o-rings on the DAVCO
Happens all the time, an o-ring will fall out or get pinched and the truck will lose prime in no time. Thats why when I change one and it starts to stutter, I flat-foot it for a few seconds. If it quits, its just the filter being touchy. If it doesnt, an o-ring is gone or messed up
Learned that from experience
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