Pump impeller gaps - why does everyone set them so tight?

Ngl I had a job on the Mississippi last month where the guy before me had his impeller clearance at 1/16 inch and it was chewing up gravel like a blender. You want at least 3/16 for sandy conditions or you're just destroying your pump. Anybody else find that running a bit looser actually keeps your production steady longer?

2 comments

2 Comments

amyb544d ago

Actually, running a tight clearance around 1/16 inch is the whole point of a well tuned pump. If you're losing volume or pressure, the problem isn't the gap being too tight, it's your suction setup or maybe the wrong impeller for the gravel size. A loose gap might keep junk passing through, but it drops your efficiency dramatically and you start losing head pressure. The guy before you probably had it right for his conditions, and you're just trading steady production for raw wear. There's a reason every pump manual recommends the smallest safe clearance, and it's not because they're trying to sell you replacement parts.

charlie2693d ago

Honestly, I agree with you on that. I ran my pump with a tight gap for years and only had issues when my suction line was sucking air, not from the clearance being too close.