Johnson HD25

58rude

Petty Officer 2nd Class
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Nov 3, 2010
Messages
175
Hello everyone. I’ve got a little hd 25, that I need to know if it’s got a tale tale of any kind. I’m figuring since it’s a 1946-1950 it probably just comes out the exhaust. Thanks a lot.
 

racerone

Supreme Mariner
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Dec 28, 2013
Messages
36,033
Most of those had a wee hole drilled in a pipe below the block I think.
 

wrench 3

Commander
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Aug 12, 2012
Messages
2,108
Most of those older engines that I've run into had an exhaust vent above the water line that blows out an exhaust and water mix.
 

F_R

Supreme Mariner
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Jul 7, 2006
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28,195
Those answers go me to thinking. It certainly is true that TD models had that hole in a copper tube, but I'm trying to remember if it applied to the HD models. Either way one or both of the two above answers is correct.
 

58rude

Petty Officer 2nd Class
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Nov 3, 2010
Messages
175
I’ll let you guys know. I’ll use my hand to check the temp, if I don’t see something. Thanks a lot.
 

racerone

Supreme Mariner
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Dec 28, 2013
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36,033
I think those used a " wobbler / rotor " type pump behind the prop.-----An easy item to inspect.
 

58rude

Petty Officer 2nd Class
Joined
Nov 3, 2010
Messages
175
Thanks for the responses guys. I’m having serious issues resetting my password and logging on. I have a new coil coming, it won’t be here till next Monday. I put a new wobble pump in it. I did find a whole in the leg, right under the transom clamp on the side, weird place but it’s the only one I see, there are no exhaust holes on the leg. I’ll let you guys know when it’s back in one piece. Thanks again!!
 

58rude

Petty Officer 2nd Class
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Nov 3, 2010
Messages
175
Can’t figure how to edit post . I meant, hole, not whole.
 

jimmbo

Supreme Mariner
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May 24, 2004
Messages
12,944
HD 25 was made from 1946 thru 1949
2.5 HP
Bore 1 3/8"
Stroke 1 3/8"
max rpm 4000
Spark Plug J8J

A lot of service info is in this manual
http://www.boatinfo.no/lib/johnson/m...hnson.html#/24


My younger brother aquired one of those motors back in 1973. Never could get it to run without overheating. Weird Carburetor on it too
 

58rude

Petty Officer 2nd Class
Joined
Nov 3, 2010
Messages
175
Ok guys, got it running. There are two small holes, halfway down the leg ,that spit water out for the tale tale. Thanks a lot!!
 
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