I recently found out when purchasing an eBay Gusher coolant pump for my 4020 that the same part number (1P3-L) could be a pump either with a start-up capacitor mounted externally on the casing, or internally wired. Both could also have either a 1.8amp or 2.2amp rating. Shouldn't make a difference, right? They should both work, right? That's what I thought when purchased...no biggie. Mount and make chips.

Well, the pump I purchased used, and rated at 1.8A and with internal startup (along with a costly rebuild to boot) will blow the little Wickman 5A (ELE-1489) fuses at startup. Testing with meters have showed the load on the motor at startup is right on the edge of being 5 amp (4.9A) before calming down when the motor gets up to speed. Apparently, the externally mounted cap is what the machine likes...not the internal (as it apparently takes too long to get the motor spun up...then pops the fuse).

I have verified that this is not a machine issue. Another Gusher I have on another 4020 (external startup cap equipped) works just fine on this same machine.

Now...the 10,000 dollar question...

I'm in deep on this eBay internal startup 1.8A pump. I'd like to use it as it runs utterly fantastic and in great shape. It just starts up with more of a load (and longer duration) than the machine likes. Could I bump up the amp rating of the Wickman fuse in the cabinet to say, a 7 amp and be "OK"? Anyone ever tried that? Or at least has experienced a similarly-faced situation? I'm just not sure how to handle this.

Thanks for the read folks.