77' 25HP Powerhead compataibilty

[slader99]

I have a 77' 25hp johnson seahorse shortshaft. The powerhead is great on it but I needed a longshaft for my transom. Does anyone know off hand which years and size johnson would be compatable? (ie. 70-79' 20-35HP?)

(I am looking at a similar year 20HP long shaft to steal the bottom drive from, but don't want to purchase it if it wouldn't work.)

Thanks,

Colin

 

[tashasdaddy]

Re: 77' 25HP Powerhead compataibilty

compare here: http://shop2.evinrude.com/ext/index.aspx?s1=bf6ad09c53cead335fcfd8a6471c0f7f

 

[slader99]

Re: 77' 25HP Powerhead compataibilty

thanks for the link, that will prove very helpful.

I noticed on the site that Johnson 20HP was only listed pre '73 and post '85, is that correct? The 20HP I am looking at doen't have a serial/model number and the owner has no idea of the year but the cover design looks similar to my 77' 25HP.

Heres a pic of the mystery 20HP longshaft, would anyone be able to guess the year by the logo/powerhead style?

Thanks,

Colin

 

[TN-25]

Re: 77' 25HP Powerhead compataibilty

The 25 was completely re-engineered for 1977, gaining a larger displacement block and a new lower unit (finally replacing the 1955-1976 style). I believe the block was based on the then new 35 which was introduced for 1976.

1977 was the year that Johnson switched back to painting their motors white (the first time since 1966).

I am not sure just how long Johnson used that lower unit (35/30 used through prop-hub exhaust while the 25/20 did not) but it might have lasted beyond the 1990s (I'm not really sure).

Johnson produced the original 20 & Evinrude the 18 through 1973 then dropped them.

In Canada they brought back the 20 as both a Johnson or Evinrude for 1975. They had a built in 45 watt AC outlet with a rubber plug to conceal it. I also remember them new in the showroom, and recall seeing some lateral fins on the lower unit where the prop shaft & gears were housed. This was exclusive the 20s in Canada as far as I know (in the '75 Canadian brochure they don't show or mention that feature). The Eskimos loved those things and regularly used them to power large freighter canoes. I know they continued the 20 horse version on the next generation in 1977 and carried them through 1981 or 82 (in Canada only).