Motor Yr ID help pleas

[fishinspot]

Picked up a good running 20 hp Johnson seahorse with electric start to put on my little aluminum v-hull. The ID plate and freeze plug with numbers are not on the motor any more. Took lower unit off to put new impeller in and based on numbers on water pump housing and propeller numbers I think the engine is a 1972 or 73. I am attaching pictures to see if anyone can help me ID it from those. I'd like to order the original service manual for this so I can clean it up. Really runs good just needs some TLC. Only letting me post one pics. Have to post again for more pics.

Thanks in advance.

 

[fishinspot]

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Pic 2

 

[flyingscott]

Put up a a pic of the lower unit and look on the powerhead for a silver disc witht the model #. The hood looks around an 83/84 model

 

[fishinspot]

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Pic 3

 

[fishinspot]

The silver disc is not there

 

[fishinspot]

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Pic 4

 

[fishinspot]

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Pic

 

[fishinspot]

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Ran out and took some of Lower unit

 

[lindy46]

I don't see external coils, so it's a pre-1973. In 1974 they didn't make a 20hp.

 

[racerone]

20 hp models were marketed in the 1970's in some areas.---Just not the US market.---Good cosmetic job to make a motor appear 10 years newer than it is.

 

[fishinspot]

Like I said I just bought this engine pretty cheap and it runs great. I just need to know what year it is so I can order a service manual and order parts as needed, I.e impeller. My guess was 72/73 so if it is definitely pre73 is there a range of years that parts will fit in these? Should I order a 1972 service manual and that should work for me?

I appreciate the help trying to help me nail down a year.

 

[lindy46]

Looks like '71-'73, but with a later year cover. The air silencer cover looks like a '71-'73.

 

[fishinspot]

Thanks all. I'll see if 71-73 use the same manual and go with that.

 

[F_R]

Powerhead color is ok with that time

 

[fishinspot]

Thank you. I got the new impeller in and now I can't get it to start. Electric start works, I get it to start with fuel poured in carb. Or starting fluid but it immediately dies again. Looks like this will take some work :-(. Ron great when I bought it a couple days go!

 

[racerone]

Is the choke closing and staying closed during cranking ??-------If this is your first motor it may take some time to learn the starting / operation of these fine motors.------The design was in production for almost 20 years.

 

[lindy46]

Fuel delivery problem? Try starting it and pumping the fuel line bulb, and see if it continues to run. If it does, but dies when you stop pumping, you have a fuel pump problem. Have you done any work on the carb?

 

[fishinspot]

I did find the choke staying closed initially. Fixed that and it's still having same issue. I'll try pumping the bulb this morning. I just bought the engine a couple weeks ago. I'm thinking their might be buildup in the carb. Also. Maybe float sticking??

 

[racerone]

Does spark jump a gap of 1/4" or more , yes or no ?

 

[jbcurt00]

Fishing, you can post more then 1 pix per post, 6 or 10, actually