I just switched to a marine kinetic cam and lifters setup. I have what I believe to be a distributor from a carbed HP 500. Not sure what's needed to verify that. So the gear that cam came with, I tried to install with a new bushing I ordered online, which was part number 1290931. When I started to install gear and pin the distributor got really tight and won't spin at all. The pin is half in. Can I run the distributor without that washer "bushing"?

I take it the cam needs a melonized dist gear???
That is a shim and they make they in different thicknesses. You want .010-.020 of end play.
You also need to check dist gear alignment with the cam gear to make sure of correct contact or you'll wear out the dist and/or cam gear.

Apparently it's not melonized, it's just parkerized.
So, pull the shim and check the end play?

The hole in your new distributor gear may not have been machined in the correct location. I'll have to dig up the info later, but I remember having to drill a new hole in the gear.

many of the ones I was sent were not drilled correctly. I stopped using cams from them for several other reasons.

That would be awesome thank you

If you would could you PM me reasons why? If not I understand, do you happen to know an alternative gear to use?

Install the gear w/o any shim and then measure how much end play it has.

zero end play.

Try a non Chinese gear. if distributor was fine with old gear and no shims with new gear equal zero, throw that gear away
jmo