1955 25HP Big Twin Sanity Check....

Solomon_Man

Petty Officer 2nd Class
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Sep 16, 2009
Messages
110
All,
I have a 1955 Evinrude 25HP Big Twin (serial begins 25018) and it currently does not have a tiller nor a electric start.

I have recently located the lower unit for this outboard as it was not existing when I received my late fathers outboards and a few boxes of misc parts for these 1950's outboards. This old outboard was by far the worse of the kept outboards but is the last I have to deal with. The other kept outboards(3) have now all new new impellors, carb kits, and complete ignition systems (points,coils, wires,plugs) and are mounted on my boats/family member boats.

I am wondering can I add a electric start and a tiller to this old Big Twin. I have read the Duck Works page about the tiller swap so I have a strong belief its a possibility but can I add the electric starter?

I have a 3 starters and 2 starter mounting plates but before I go digging into this little project I need a sanity check is this a possibility and is there any "gotchas" that I may run into.

Thanks,
Chris
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,195
Re: 1955 25HP Big Twin Sanity Check....

You also need a flywheel
 

Solomon_Man

Petty Officer 2nd Class
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Sep 16, 2009
Messages
110
Re: 1955 25HP Big Twin Sanity Check....

You also need a flywheel

Please elaborate on the flywheel....Not sure whats on it currently as I have not looked at it in about year...Probably does not have "teeth"....Going to work on it this weekend after building another outboard stand.

I may have an extra flywheel that may match as I have a complete Powerhead (starter/carb/pull start etc.). Just the power head assembly. I am unsure of the year but I believe I have the title for the motor. It was all part of my dad's estate closing that everything that has a title would. Since Ohio requires it (even to dispose, we were told), I almost positive I have the title back at the home office.

Is there any specific years I need to look for...maybe I will get lucky and I have the starter/flywheel already and just leaves me finding a decent tiller.

Thanks for the reply,
Chris
 

Chinewalker

Fleet Admiral
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Aug 19, 2001
Messages
8,902
Re: 1955 25HP Big Twin Sanity Check....

It'll be a toothed flywheel from a 1960 & prior Big Twin style motor. Check the hub for cracks between the threaded holes...
 

Solomon_Man

Petty Officer 2nd Class
Joined
Sep 16, 2009
Messages
110
Re: 1955 25HP Big Twin Sanity Check....

It'll be a toothed flywheel from a 1960 & prior Big Twin style motor. Check the hub for cracks between the threaded holes...

Sounds like I may be in luck then. I am positive that all the outboards titles were in the 1950's (latest year I believe was the 35hp (1958) which is on my little 14ft Lonestar Monterey now). This donor has teeth and a starter/mount.

I believe the powerhead parts unit was from 35-40hp outboard. Not sure if Johnson(Sea horse/?) or Evinrude (Big Twin/Lark). Does the Johnson or Evinrude make a difference?

I will pull the serial from the Welch plug tonight when I get back to home base....probably take a good look to see if they may match visually...Also I will look at the title to see the year and get confirmation.

Thanks,
Chris
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,195
Re: 1955 25HP Big Twin Sanity Check....

Johnson and Evinrude are totally interchangeable except for the hood and hood mounts. BTW, speaking of that, the starter bracket is one of the hood mounts, and Johnson is kind of "special". It will work on the Evinrude, but not the other way around. That makes the Johnson bracket somewhat more valuable due to it's rarity.
 

Solomon_Man

Petty Officer 2nd Class
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Sep 16, 2009
Messages
110
Re: 1955 25HP Big Twin Sanity Check....

All,
The outboard serial number begins with 35530.

So I believe its a 1962 Evinrude 40HP Lark?

Will the flywheel and starter bolt up?

Thanks,
Chris
 

Chinewalker

Fleet Admiral
Joined
Aug 19, 2001
Messages
8,902
Re: 1955 25HP Big Twin Sanity Check....

The donor motor is the 40hp Lark? If that's the case, the starter may work, but the mounting bracket won't have the cowling support bits. And, the flywheel will NOT work as they changed the crankshaft taper in 1961 after they started busting cranks with the 40hp models...
 

F_R

Supreme Mariner
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Messages
28,195
Re: 1955 25HP Big Twin Sanity Check....

Starter bracket won't have the silencer support extension either. The 1962 and 1955 are VERY different motors.

BTW, what is the complete serial number of that 1955? I may have some other news for you.
 

Solomon_Man

Petty Officer 2nd Class
Joined
Sep 16, 2009
Messages
110
Re: 1955 25HP Big Twin Sanity Check....

Starter bracket won't have the silencer support extension either. The 1962 and 1955 are VERY different motors.

BTW, what is the complete serial number of that 1955? I may have some other news for you.

Serial 25018 06109
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,195
Re: 1955 25HP Big Twin Sanity Check....

The news is good. There were some motors built that year that had problems with the crankshaft seal. Yous is OK.
 
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