20" or 25"? How do I know what I need"

[bart98stang]

I just acquired a 1992 Sunbird SPL 194 Cuddy Cabin boat that needs a outboard. It currently has Mercury controls and I have no idea if I need a 20" or 25" shaft engine. Can someone please educate me on which one I need and please explain. Thank you very much in advance.

 

[ondarvr]

Re: 20" or 25"? How do I know what I need"

measure the transom, you will then know.

 

[Texasmark]

Re: 20" or 25"? How do I know what I need"

measure the transom, you will then know.

If I may sir elaborate:

The measurement is from the clamp bracket cut out in the transom vertically to a line extending out from the bottom of the boat....like put a straight edge on the bottom with a couple of feet of it sticking out. On the engine this is the distance from the clamp bracket where it mounts on the boat to the anti vent plate....the plate just above the prop. There will usually be differences in these measurements, but not by 5" and that's your clue. For most applications you want the AV plate at or slightly above the line extended from the bottom; depends on type of setup, boat function, and usage requirements.

Mark