28hp super sea horse compatibility

CaptainGoodboy

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May 31, 2023
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I have an rx-10 Johnson 28hp from the 60s I was wondering if parts are interchangeable from later 28hp models from the 70s?

Thanks everyone
 

racerone

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Dec 28, 2013
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No they are not.---Totally different motor.-----Well , ---maybe a few nuts and bolts.-----What parts are you looking for ?-----What is your motor doing / not doing.-----Your location ?----Lots of used parts available.-----Marketed as a 28 in 62 / 63 / 64.----Then with minor changes as a 33 HP from 1965 to 1970.
 

CaptainGoodboy

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No they are not.---Totally different motor.-----Well , ---maybe a few nuts and bolts.-----What parts are you looking for ?-----What is your motor doing / not doing.-----Your location ?----Lots of used parts available.-----Marketed as a 28 in 62 / 63 / 64.----Then with minor changes as a 33 HP from 1965 to 1970.
I found a good parts motor for cheap. He doesn't know what model motor it is offhand(stored at a different location). Its a 28hp super sea horse, he thought it was from the 70s. I'm not sure if they made the 28hp in the 70s. But if its a 28hp from around that time, are most of the parts interchangeable? From the pictures it looks identical.
 

racerone

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Simple hard fact for you.----They marketed a 28 HP in 1962 / 1963 / 1964.------No other 28 HP models are compatible !!
 

CaptainGoodboy

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Simple hard fact for you.----They marketed a 28 HP in 1962 / 1963 / 1964.------No other 28 HP models are compatible !!
I lucked out and its the same motor. Are you fairly familiar with these motors? It's running rough and not much power on the top end. I was think a carb clean, coil packs, points, and plug wires. Anything you suggest?
 

racerone

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Fairly familiar ??----I started working at a Johnson dealer in 1968 !----It was an everyday motor at that time.----Today I have a bunch of that type of motor for parts.----Know them inside out !
 

CaptainGoodboy

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Fairly familiar ??----I started working at a Johnson dealer in 1968 !----It was an everyday motor at that time.----Today I have a bunch of that type of motor for parts.----Know them inside out !
Hey that's really cool! Do you have any suggestions on brands or companies to get replacement parts for these older Johnsons. Also I'm trying to pick up some fuel line and I'm not at my shop. Do you recall common fuel line sizes for those engines. I think its 5/16 to the pump and 1/4 to the carb?
 

tphoyt

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Jun 10, 2010
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1,221
Lots of places to find parts with a little effort looking. Might even try here on I Boats.
As always oem is best and Sierra is the next best thing for me.
 
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