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18hp Johnson block inspection

S

shinola

Contributing Member
I'm replacing the spent 57 Evinrude powerhead with a 58 Johnson that I got off of ebay. I'm no expert at what I'm looking at, so I thought I'd post some pictures to see what the experts here think. First, here are the cylinders.
 
And finally a view of the top of the crank of each motor. The Johnson has a "splined" feature that's not on the Evinrude. Any issues with that?
 
The " splined feature " appears to be a broken part of the magneto plate bushing.-----As for the piston & cylinders they look like garbage to me !!
 
Hope you didnt pay much for it..like Racer stated the cylinders are junk. The "splined" piece looks like a bushing that was knurled to take up slop on the 58 armature plate..
 
Just more proof that some " sellers " on Fleabay do not know or care as to what they are selling.-----Everything looks in " good condition " and everything will " likely run " -----That my opinion !
 
Would a compression check be the first step to see which way to go? The cost was low, but I still was hoping to make it work. Any other sources I should look at for good powerheads? They seem very hard to find now. timguy was looking but couldn't find one, and this looked like a "low-cost" possibility.
 
Compression or not, the one piston shows scuffing on the skirt and rings, Can't see the rest without turning it over a bit. Will it run? Maybe. How well? Not like it should. How long? Time will tell.

Agreed, it has thee remains of a broken armature plate. Not a big deal if you have a good one.
 
I am going to be blunt here.-----Start listening to advice here.----Take it apart for inspection first.------You would have to find O / S pistons and rings if needed !!----Then find a shop to do the machine work.----Best to join the local chapter of the ---aomci------You will find members there who will help you and not charge big money for junk !----Or drive 1500 miles as I think I have some good parts motors ( reasonable $ ) to fit that.
 
I clearly got too excited over this one. I'll look for a chapter, I had read a little bit on that club a few weeks back.
 
I found a 58 on craigslist a while back for $100. Like only a few hours on it. They are out there. Keep looking
 
Good luck Tim. I know what you mean about snowmobiles. I'm from Woodruff Wi myself. But now luckley Fl.
 
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Good luck Tim. I know what you mean about snowmobiles. I'm from Woodruff Wi myself. But now luckley Fl.
 
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There must be a snowmobile forum out there, but I have focused interest in just the old Ski Doos. Run em love em...trust em.....with my life.....got lotsa stories, true stories....NW Ontario -50, slush, nobody for miles...no trails, no gas....little hope, but guess what? That 1969 Olympic 12.3.....always got us back to camp. Couldn't GIVE me a new machine.
 
Nothing wrong with the old Cats....I even had the Panther with the Wankel motor. Here is a Johnson Wankel....remember?
 

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Did they ever try a Wankel on an outboard? Really unique/cool exhaust note.....how about a motorcycle. Noisy Harley's are getting obnoxious now....the novelty is wearing off for me.
 
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Sure I have a ---Mac 10----An Italian made ( 1972 ) outboard motor with a SACHS Wankel powerhead.-----Picked it up ( $50 ) years ago just to see how it was put together.----Just a parts motor.----Find examples running on Youtube off course.----Interesting item.----Not a really well built item in my opinion.
 
Holy balls, 7000 rpm? Wonder what it sounds like? I always thought we could go places with the Wankel. Sister in law had one in a car. Tuned it up for her. Not much torque, but could it wind up? Now with CVT's.....constant velocity tranys.....able to keep these motors in their narrower powerbands, maybe the Wankel will see some hope. So simple, add fuel injection....ceramic or carbon fiber composites.
That compact Mazda used quite a bit of oil, but produced over 250 hp.....emissions and fuel economy nailed the coffin.
Apparently a hybrid electric/Wankel marriage is in the works at Mazda.
Sorry for getting off topic, but it's snowing like heck here and nobody's bringing me any boats.
 
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