Johnson 20CR78C

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May 7, 2018
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22
Greetings all, I purchased this 20 hp Johnson partially worked on. I am trying to find a factory service manual for it to get it running properly. The issue I am having is confirming the year of the outboard but the tag appears to id it as a 1978. Is this correct? I can't seem to find any parts listing on-line either for this year. It won't take much I think to get it going, I will have to reinstall the flywheel and recoil. But before that, I want to be sure of the point setting and timing. It has been converted to electric start and the choke knob has been removed to make room for the cables going to the starter motor. Any help would be greatly appreciated.
 

F_R

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Jul 7, 2006
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Was your motor built in Canada? I think CR means Canada Derated. OR....it might be a Commercial motor, Or both. That MIGHT be why it has points. Anyhoo, it is a 1978. Perhaps our Canadian members can shed more light on this.
 

racerone

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Dec 28, 2013
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There are no points in that motor !!----Time to post some pictures including the cowling if original.---You use the 25 HP to find your parts.-----Your location ?
 
Joined
May 7, 2018
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Hello again, thank you for the quick response! I am in Canada and the cowling has 20 on it. Racerone you are correct, there are no points. It looks like a type 2 cd ignition system in it. I was given a Seloc repair book for Johnson/Evinrude but I don't trust it and that is why I wish to purchase a factory manual. I try to look up 20hp for 1978 and there is no such listing anywhere. I will try the 25hp suggested and see where I get. I will take some pics and you will see what I'm trying to deal with. Thanks so much, Rick.
 

racerone

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I might have a paper copy of a 20 HP --1978----If in Ontario I might be able to help with spare parts for that.----Your location ?
 

racerone

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The decals suggest an 81 model.-----Someone added the electric start with electric primer.----Shelburne is less that 2 hrs from me.----I do not like the spray bomb paint work.
 
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May 7, 2018
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I bought an 18 hp and this 20 for $100. I got the 18 going with just a bit of work. Now this one is on the work bench. If you look at the last pic, the silver rod under the pick-up mounting plate I think is missing a part. In turning the throttle handle and looking in the carb bore, I am not getting a full throttle opening. Also, on the fuel solenoid, what is the correct position of the red lever to run the engine? I will have to figure out where that loose wire loop goes as well.
 

racerone

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The red lever is shown 180 degrees out of position for normal running.
 
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May 7, 2018
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The fellow I purchased the outboard from is a retired mechanic. We have coffee in the morning at our local cafe'. The guys and me often rib him about his repair ethic and wonder if he is ever going to finish the bent shaft repair of his snowblower he has been working on for the past couple of years! So when I purchased the two outboards, I expected a challenge and I am not too fond of the paint job either. In getting the engines, I had to pull out a bunch of stuff from his shed including a snowblower with two flat tires. He gave me a container with all the bits and spare parts from him working on this Johnson.
 

racerone

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Dec 28, 2013
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Post compression numbers for that motor.----Yes every town used to have someone who could help with simple repairs.----Those characters are disappearing.
 

racerone

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What is the model # on the transom bracket.-----That may not mean much as this motor has seen some work.
 
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May 7, 2018
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The guy I bought it from put new pistons and rings in it. I wound it over with the plugs out and it seems like there was alot of pressure coming out of the spark plug holes. My compression tester is acting up so I couldn't get a full reading. It went to 85 on the first stroke on both cylinders but I couldn't get the gauge to work right.
 

racerone

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Why did he forget the adjustment piece on that thin throttle rod ?
 
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May 7, 2018
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He gave me a brass piece that looked like it belonged to that rod, but I misplaced it and will have to make one. I tried the electric start last night to give you some compression readings, but it wouldn't work off the key so I used booster cables and went direct to the starter motor. The best reading with a squirt of oil in each cylinder was 75 psi. The starter motor had a hard time turning because of the compression with the gauge on.
 

racerone

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Dec 28, 2013
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If the starter had a hard time turning it is due to a bad battery.----Or bad starter.-----Pulling it over with rope will get the compression readings.
 
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