Old Johnson engine

[capt.phil]

I have an old Johnson outboard I'm trying to find info on. Any help would be appreciated....on the top of the motor are the words Johnson Motor Co. Waukegan, Ill, with the model number J-25 and the serial number 131648. Thanks for any help...Phil

 

[wbeaton]

Re: Old Johnson engine

J-25 is a 1.5 hp built by Johnson between 1925-32. Your serial number would be a 1930.

 

[tmcalavy]

Re: Old Johnson engine

Wayne is correct again. Your J-25 uses a Champion M5J or D9J plug, gapped at .030, point gap is .020 and fuel mix is 1/2 pint oil per gallon of gas. If it doesn't have spark, clean and reset the points...with any luck it'll spark again. If not, the coil may be toast...if so, be patient while you try many avenues trying to find a new coil. Be careful running it in a barrel, as the water pump relies on forward motion of the boat to prime/supply the vacuum/siphon water pump. Don't run it too long stationary or it will over heat. Good luck with it. Can you post a photo?

 

[JB]

Re: Old Johnson engine

My book calls for Champion C7 plug. Are the M5J and D9J replacements for that?

 

[tmcalavy]

Re: Old Johnson engine

The 5MJ was the original issue plug for the J-25, later replaced by the D9J. I show the C7 as being the same as the D16, but my cross-reference list is probably not so current.