Flash Output InConsistent Among 3 540ez Flashes

I bought 3 540ez flashes used for my strobist setup. They all work and appear to be in the same condition. However, one of them seems to be not as bright as the other 3.

I tried swapping out batteries and it is the same

"seems to be not as bright"
?
How are you measuring/comparing?
Does the motorized zoom on all of them appear to work properly, and are you comparing them all at the same zoom setting? Are they all in manual mode at the same power setting?

Wow, that's a mighty difference in power. I'm not sure you can even get a 540ez repaired nowadays, so good luck XD

hmmm, by any chance did you get these on craigslist?

xknowonex wrote in post #12636663
They're at all the settings but I just noticed that the zoom motor one on the dimmer one doesn't work and make noise like the other one.

How much does it cost to repair? Or should I just sell it off as is for parts?

Repair would cost more than it's worth.

Experiment more with it, try different power settings, see if you can figure out what zoom setting it's stuck on. It's probably still useful, just not as versatile. But you need to come to an understanding of its limitations.