Evinrude/Johnson snowmobile rotary

Picked this thing up local for too much money. It's really hard to find any of these and even harder to find any info on 'em so I'm gonna try to get it running and document as much as I can. Would be cool to put on a minibike or something since it can apparently make around 35hp

There's not a whole lot to go wrong on these since they're a rotary but there's a secondary butterfly that likes to loosten itself and get sucked into the engine, so a main thing is to take it apart, clean it, and make sure the butterfly is where it's supposed to be and not scraped up alongside the rotor housing

The biggest thing I can recommend is to find the repair manual online, it goes way in depth about everything and tells you step-by-step how to take it apart and clean it, if not lmk and I can throw the pdf I found on google drive or something

Day one

It's missing the carb, power pack, coil, and rectifier, but it at least still has all the wires attached and the stupid rare plug. It's clearly been sitting for a while but it's not in bad condition. A mouse or something had also made its home inside the fan shround at one point too

For the most part the manual walks ya through it pretty well, mostly just unbolting things, only time i had to get creative was with the flywheel nut, where i had to put a pipe wrench on the cvt and hit a crecent wrench on the nut with a hammer to get it off since an impact socket wouldnt reach that far down the shaft

kinda looks cool without all the shrouds on it

looks like the secondary didn't grenade itself, that's good

probably the first time it's been opened since it's been made

The rotor was coated with carbon and has one very small spot on the face with some pitting, but I don't think it will be that big of a deal in the long run seeing how nice of condition it looks overall. Most of the seals came out no problem but I'm gonna let it sit overnight in simple green due to a few being rather stuck in there.

that's definitely never been cleaned, wonder if all the carbon raised compression a little bit

all the key parts look to be very smooth and as they should be

the manual recommended to set it on a table with a hole in it, a couple'a board will do

After I get everything cleand and all the seals sealing as they should I'll put the housing back together, and sometime wayyy in the future I'll have to take the secondary apart and tap a bolt into the hole. After that it's just a matter of getting a few parts

Day two

Got all the seals and springs out of the rotor and am now letting it sit overnight in degreaser after scrubbing a lot of the carbon off'a it. Theres a small chip in a non compression part of the housing but I do not belive that this will cause any problems.

After this I removed the secondary valve and tapped the hole it was in, slapped some gasket sealer on a bolt in there and am currently letting that sit too

I should probably buy a handle for tapping

bad triangles get sent to the simple green chamber

so glad non of these broke, would probably never be able to get replacements

Day three

Cleaned and lubed everything and slapped the whole housing assembly together. Compression kinda feels better but upon torquing the through-bolts I stripped out one of the nuts. I'n not sure if it's just because of the metal being old or if my torque wrench is bad but I'll probably buy some new bolts for this anyways

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