80's johnson 8hp questions...

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swfl mike

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Recently an 80's johnson 8hp was given to me. Model number j8rccs (anyone know the year?). I was just curious as to what kind of power these things produce. I was told these model years were fast and it is just about as heavy as my merc 15, so I was wondering where it would stand compared to say a 9.9 or a 6 horse. Thanks for any responses
 
Vic.S

Vic.S

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Re: 80's johnson 8hp questions...

Its a 1988 model (CC are the date letters)


Power .... 8 hp, a bit more than 6 hp and a bit less than 9.9. It weighs the same as the 6 hp model of the same age and spec but less than the 9.9.

Approx weights, 'cos not sure about that year, 6 and 8 hp std shaft 25kg, 9.9 std shaft 33 kg

The 9.9 is bigger cubic capacity engine 216cm? compared with 164 cm? for the 6 and 8.

BTW it should be run on 50:1 even if the decals and manual still say 100:1 !
 
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swfl mike

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Re: 80's johnson 8hp questions...

thanks thats great info. The reason I ask is because I have a '72 6hp evinrude that can't even come close to getting my 14ft jon boat on plain. The guy that gave me the 8hp said it got his slightly smaller jon on plain easily.

What I'm askin is, is there a decent power difference between my older 6 and this newer 8, because my six has no power
 
Vic.S

Vic.S

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Re: 80's johnson 8hp questions...

Ah, once you go prior to about 1983/4 you'll find that the power ratings are different.

Older models were rated at the engine, ie power from the crankshaft, but newer models are rated by the power at the prop shaft. Icomia 28/83 is the document that describes the testing/measurement procedures.

So a late 1980s 6 hp is more powerful than a 1970s one, and late 80's 8hp is going to be quite a bit more powerful.

Id guess that your 1970s 6hp would measure up at less that 5 hp if tested in accordance with Icomia 28/83.
 
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