---

Last fall I found my needle in a hay stack! I finally found a 40hp Yamaha 2 stroke short shaft. This weekend I am going to start the install and just inquiring if there is anything I need to watch out for? This will be going on my 1971 13' Sport. You can see pics in my info. There are no bolt holes in the transom yet. Any help would be appreciated. Also I have researched and the whaler mfg resources say to put the cavitation plate just below the hull. Is that correct? What do you think? Motor also came with hydrofoil. Should I take it off and see how the boat acts without it?

Thanks
Ed

---

Ed,

If' it's power t/t and at the correct height, I wouldn't think you'd need the hydrofoil. I have an early 70's Sourpuss (for sale) that runs great, and when trimmed properly, feels like you pick up 5 mph. That's with a 4 blade prop....

---

AV plate below the hull line is old school. Modern practice is to install so that when planing, you can just see the AV plate at the water's surface. This usually means the AV plate sits about 1 inch above the hull line. With this configuration you likely won't need the foil.

---

Drilling holes is the critical step. You do NOT want to use lag screws in the bottom two holes, rather use the slots.

There is a diagram showing the right layout. Measure 3x, drill 1x. Read all the contents
http://www.whalercentral.com/articles...icle_id=82

You don't need a foil or a 4 bladed prop.

With a decent stainless prop, mounted high, you can expect 32-34mph running solo and light.

---

I can't help on the mounting but that is the same setup I have on my 1985 13. Boat moves even when I have my entire family in it.


(fixed typo in year)