Swap 79 100hp power head into 94 115hp jetboat?

[fnracing]

Looking for a replacement powerhead for the 115hp Evinrude/OMC turbojet. Other then the obvious connections, does anyone definitively whether the PTO side of the cranks for the above engines are the same diameter/length? They both use the same gasket to bolt into their respective lower units leading me to believe that they have the same bolt pattern.
Thanks for your advice..

 

[racerone]

The 79 has the same bolt pattern.-----Spline count is the same between the 2 motors as well.-----There were some changes on outboards to do with crankshaft / driveshaft length and fit in the early 1990's.-----I know what you have and are trying to do !----Worth a try I would say.----Where in Ontario are you ?-----I may be able to help you first hand.----Best option is to rebuild the existing powerhead , but that is only my opinion.---Many would argue that.

 

[fnracing]

Located just out side of Midland. Have a barely running 115 that I inherited with the boat along with 3 bins of additional motor parts. I can buy the 100hp for $500 or spend up to $500 on rebuild. LOL. What to do, what to do...

 

[racerone]

You are about 2 hrs away.-----I recommend you rebuild the existing motor.---

Mod EDIT: PMs only fellas

 

[fnracing]

Ya that's what I'm thinking

Mod EDIT: PMs only fellas

Cheers

 

[racerone]

Is the 79 powerhead guaranteed good ??----Have you done a compression test on the 79 powerhead ?----Swapping a 79 onto a 94 may not be a good idea.----Lot of work to find out that it still will not perform.

Mod EDIT: PMs only

 

[jbcurt00]

..........

Mod EDIT: PMs only

Check your PMs racerone

 

[jimmbo]

There will quite a power drop as the 79 100hp is crank rated and the 94 115 would have been a prop rated engine powerhead.

I vote with racerone to rebuild the current powerhead, unless the block is not rebuildable