How dependable are old scool johnsons

[Reeya]

Considering a purchase for a 50 horsepower Johnson outboard.. to put on the back of my 17 ft Palm Beach center console curious if anyone knows the reliability factor of these motors considering it's a 1974 that'has 500 hours of freshwater use and the motor looks very clean and recently had aprofessional tune up... if it is everything that the previous owner is saying would this motor be something I can considered reliable for the next 2 to 4 years... until I have the cash to upgrade to something newer

 

[schematic]

very dependable.....if it has been properly maintained...
water pump?

 

[F_R]

They had some piston ring breakage problems. But hey, anything can break, even new ones.

 

[jimmbo]

74, I consider those engine new, modern, old has to be from the 50s

a 74 still had the large gearcase and used the same props as the V4s, allowing for some pretty snappy acceleration on small boats

 

[Tassie 1]

Could last 5 minutes or it could last 5 years or more,
no one here knows if it's been thrashed or babied,
whether it's been looked after or just cleaned up,

is the block the same color?
No redness around the cylinders ( overheated )

do a compression test at the very least,
how much is he asking?

 

[Keyboardman]

I had a '74 50hp on my old tri hull. Great engine, never let me down in 3 yrs. Carbs were a pain to set just right and mine idled like an old Harley but, never stalled. I sold it for $500 after I swapped it out for a '76 75hp Stinger. I think the old 70's era engines are solid as a rock.

 

[boobie]

I'll take those older motors any day compared to the newer ones. Didn't need a computer to work on them and less "junk".

 

[thatone123]

In general some of the most reliable ever. Many models also the lightest power to weight ratio. Internal parts on some models are industrial type and over engineered for super reliability, especially compared to some new ones. Put the wrong longer plug in a 70's era 20 hp recently. To my surprise it ran great and I found out the plug had no gap as it was smashed up against the bottom of the plug by the piston. Still ran right as rain. Oh. well, so much for proper plug gap...lol

 

[jimmbo]

The very late 70s had a 20hp that used regular plugs, the same displacement 35 used surface gaps, with a regular plug substitute for extended trolling

 

[Faztbullet]

I would look for a higher HP motor as that motor is only 40hp at prop and on a 17ft boat performance will suffer.

 

[jimmbo]

It should be able to push the 17’ about 25 mph

 

[Keyboardman]

My heavy old waterlogged tri hull would do about 20 with the 50 on it.

 

[juno pierrat]

it might be noted: that from 1984 to 1988, 50HP, that components under the flywheel were three pieces, sensor, charge coil and stator , cheaper to replace individual parts, stator assembly's ( all in one piece) for earlier years could be 200 to 300 $