1974 Johnson 40

[SC64]

I am restoring a 1959 Cherokee Aluminum - weighs all of 300 pounds - maybe. Purchased a 1974 Johnson 40 Twin that was rarely used - I would say it appears to have less than 50 hours on it if that. When it was last operated was unknown - but it looks brand new.

- I did not actually check the compression other than to say trying the rope start qualitatively said compression was good if not great.
- Checked spark - fine
- I did buy a new impeller kit (installed) - and re oiled the lower unit with new seals etc
- I did buy a carb kit but decided to see if it would start.

Motor started right up...idled well...so I put it on the boat and in the water. First run around, starts, idles...but won't go above 1800 -2000 rpm (guessing). All the linkages seem to work well - so I figure the carb needs rebuild. I take the carb off, clean, new float, new gaskets, clean, set low speed idle...not much to these things...put back on....and exact same performance - except the low speed idle went from good to perfect - thing idles very smoothly - and starts at first crank without a choke.

have rebuilt carbs before so pretty sure I am not missing anything (also have shop manual).

The gentlemen I bough it from is a member of the classic outboard society and lives across the country - but we have been trading texts - he believes it is the high speed jet (not getting gas). The high speed jet couldn't be simpler in these carbs and it is clean as is the little brass insert at the bottom of the bowl that feeds the jet.

The motor doesn't sound like it is "bogging" - just gets to 1/3 speed and that is it. The linkages are good and the throttle opens 100 percent.

Timing? - I gotta believe it is something simple....

 

[oldboat1]

Looks like a '57 Buccaneer(?)

 

[F_R]

No Title

Looks more like a '58-59 Buccaneer. No matter, it most likely is running on one cylinder. Unless they have already been replaced, I'll just about guarantee you that the coils are shot (cracked).

 

[jimmbo]

Looking at the pic, that is not a 1974 engine.

 

[SC64]

Looks more like a '58-59 Buccaneer. No matter, it most likely is running on one cylinder. Unless they have already been replaced, I'll just about guarantee you that the coils are shot (cracked).

Thanks - If a coil was shot no spark correct?

 

[F_R]

Actually, those motors from that era all have cracked coils from age and the materials they were made from back then. And the cracked coils might be called the Great Deceiver. They may have spark. And you might even be able to get it to run a bit. But they will cause all sorts of ills such as lack of power, hard starting, refusal to restart when warm, etc. Replacing the coils and cleaning or replacing breaker points while you are in there is a miracle cure.

 

[oldboat1]

Sooo..... working on the motor shown here, or the Johnson in your other post (maybe both?)