Leg swap Early/late merc 50...do they fit?

[Nos4r2]

I've got 2 merc 50's in my garage, and due to getting a new boat I now need a short shaft... Unfortunately on the short shaft I've got the powerhead is seized solid. It's a 1973 500 Thunderbolt. The other merc 50 I have is one of the late blue band 50's or possibly a brown band (it's been sprayed before I bought it-it's the 4cyl with 4 separate coils) and it's in absolutely a1 mechainical order but a longshaft.<br />My question IS...<br />Will the shortshaft leg fit straight on?

 

[Nos4r2]

Re: Leg swap Early/late merc 50...do they fit?

btw both legs are in a1 condition, he s/shaft had just been serviced before layup but some cretin nicked a sparkplug and left the engine open for 8 months.

 

[Chinewalker]

Re: Leg swap Early/late merc 50...do they fit?

As a complete unit, from the belly pan on down, yes, you should be able to swap them, .ie swapping the powerhead from the runner into the shell of the non-runner. Base bolt pattern is the same as are linkages.... Might be some small modifications necessary along the way, but it should work....<br />- Scott

 

[Nos4r2]

Re: Leg swap Early/late merc 50...do they fit?

That's the best bit of news I've heard all day-Thanks!anyone got any idea how hard it is to fit a charging system to a late blueband powerhead? I'm not even sure if it's got one at the moment, so any hints on how to tell would be appreciated too...

 

[Chinewalker]

Re: Leg swap Early/late merc 50...do they fit?

All electric starting 50hp Mercs of the "black" era came with a charging system of some sort. Easiest way to tell is to look for two yellow wires coming from under the flywheel. They'll lead to small, squarish box with three poles on it - a rectifier. If you have that, you've got a charging system....<br />- Scott