whats the difference between these two couplers
 

one is from the 454 i took out the other is from the 502 im putting in
not sure what changes I need to make to install the 502 now

thanks again in advance[ATTACH=CONFIG]519977[/ATTACH][ATTACH=CONFIG]519978[/ATTACH]

Looks like the 454 is the long snout and the 502 has the std coupler. Same spline nothing to change.

The coupler on the right is an aluminum coupler .The coupler on the left is Mercury's heavy duty coupler made for heavier boats that idle a lot or troll alot.the quality of the hd coupler far exceeds the aluminum coupler.

There are 2 versions of the short coupler, aluminum and steel. I might be wrong, but I don't think the aluminum one is available any longer. The short one is necessary for driveshaft applications.

the one on the left is a gen II alpha coupler ,,,,
this is the heavy duty bravo coupler http://www.bing.com/images/search?q=...lectedIndex=10

the one on the right is just the standard duty big block coupler..

One is a penis the other a vagina. Your mom not teach you about the birds and the bees??

no she died when i was young a s shole...thanx your comment just brought the worse day of my life...

besides, they are both vaginas. one is just fatter than the other...

So I guess ill need ti swap them to install the 502 in my boat with a bravo?

Fixx if I`m referring to you I`ll quote you otherwise I`m replying to the OP. Internet 101 so calm down there buddy