Powerhead Match

Can I replace a 1993 evinrude 90hp powerhead with a 140hp powerhead

Re: Powerhead Match

i doubt it, with out changing a lot of stuff, exhaust adapters have different #s. etc. go to brp-evinrude, literature, engine diagrams. compare the parts.

Re: Powerhead Match

What year 140?

Re: Powerhead Match

If the 140 is a crossflow, yes. It's a direct swap. If the 140 is a looper, the simplest thing would be to put the 90 gearcase on the 140. That's about all that will swap.

Re: Powerhead Match

Thanks for the replies. Maybe I should ask my question another way. If I were to replace a 1993 90Hp powerhead what year model 140hp powerheads would swap out

Re: Powerhead Match

Any 140 crossflow will fit. (140 crossflows started in 1977) As will any other V4 crossflow from 1978 & newer.

Is the 140 you're looking at a crossflow or a looper?

Re: Powerhead Match

Dhadley I am a little stupid about crossflow and looper I do like to do as much of my own work as I can so i am trying to learn about things My old Outboard is a 1993 90hp evinrude so is it a crossflow or looper my guess it is a crossflow, or how do I tell which it is. I really haven't located a 140HP powerhead Yet I have been looking around for possible replacements for old one and thought I would replace it with as much hp as possible. I have noticed that there is a bubbleback crossflow and a (flatback I think this is right) crossflow what is the difference in these two. Thanks for any advice or help you can give

Re: Powerhead Match

Yes, yours is a crossflow. A looper is physically much bigger and has no plates bolted on the side or back of the block. Your crossflow has by-pass covers bolted to the side (each cover has 6 bolts) and the exhaust plates bolt on at the back of the block.

Any crossflow in those years mentioned above will bolt on without any mods. The "bubble back" exhaust is simply a tuned exhaust. Well, that's the theory anyway.

Anyhow, to make things simple look at your 90 block where the front half meets the block. Basically the crank center line. At the bottom there is a cast in mount with a rubber in it. A bolt goes thru that rubber into the lower pan.

When you're looking at possible "donor" motors look for that cast on mount. Earlier V4 crossflows have that mount bolted to the front half with 2, 1/4 x 20 bolts. Just to simplify let's stay away from them. Some will fit, some won't but the ones with the bolted on lower mount have a small center main crank and the wrong mounting bosses for your power pack.

Look at how your pack is bolted on (top of block, port side toward the rear). Make a note of those bosses. To really simplify things the donor block needs to have the same bosses so the pack will bolt on easily without fabricating anything.

Is there something wrong with your 90 now?

Re: Powerhead Match

The 140 crossflow was discontinued around 1984 about the same time when hp ratings went from crankshaft to propshaft ratings. The 140 (crossflow) survived and became the 110 and finally the 115. If you want minimal conversion problems, look for a 93-95 115 hp crossflow. They have the bubble back exhaust and the larger carbs just like the 140's. Propshaft rated, it will perform nearly as well as the old 140's.

Re: Powerhead Match

Along with the powerhead, find an appropriate hood or change your decals accordingly. Always appropriately represent the horsepower of your motor. Never do such modifications to cheat statutory limits. Never do such modifications to cheat boat capacity. Knowledge of such modifications usually dies with the modifier, or is quickly lost in the chain of ownership. Make certain that you do not inadvertantly contribute to that motor getting into an overpowering situation. It could come back to bite you years after you forgot you even had the thing due to another's imprudence. Without proper identification, figure that no reputable dealer will touch it if you need service, or that if they think it's a 90 they'll be using 90 parts and specs.