Seawater pump pulley wobbles
 

I just replaced my 454 merc Gen ? seawater pump (fuel pump attached) with a supposedly new unit. I noted that the pump pulley has a pronounced "wobble." The shaft seems to be straight, but the pulley is like "cocked off." I think I recall a similar wobble on my old seawater pump, but always figured that some mechanic must have dropped a hammer and bent the thing. The new unit seems much more pronouned. Is this normal? Or was I sold a bad unit. Thanks.

Its probably pressed on crooked.

Previous boat was same way. I was able to clean up the pulley a bit from where it sheared itself on, then press it on just a bit further onto the unsheared bore. Just a 1/8" or so more I think, not enough to put the belt off alignment. Might be able to place a couple washers behind the mounting bracket to move the whole pump out if you have to press the pulley on to far for a straight running belt. Just a thought.

I've seen this several times, pulley can get distorted because it is stamped steel. I put a Gen5 motor in a boat a few years ago and ended up smacking the pulley with a hammer until it ran true. Don't hit too hard just be patient and finess it. BBB

Options: Beat it, Return it, or live with it?
 

I 'm trying to decied if I should return the thing, try to straighten it, or just live with the wobble; the wobble seems bad but the belt does seems to track straight on the idler and crank pulley. I really don't want to pull it off again cause it is a pain and will burn another weekend, can you straighten it by pounding it with a hammer while installed? Can that damage anything else like bending the shaft. Did the Parts guys (Lighthouse Marine Supply) sell me a bad / remanufactured part when I thought I was buying new? Or is this wobble common on new pumps?

Mine had some wobble also and I never had any issues. Just not sure how much off your is without being able to see it.

Return it. Probably will wear out the bearings over time, or cause the belt to jump if running hard or hitting hard seas.