Used Johnson Stinger 75hp opinions?

[Keyboardman]

Hi all, I'm looking at a Johnson 75hp Stinger along with another Johnson 75 and an Evinrude 75 part engine. All years unknown right now. I'm looking for opinions on these engines. Are they any good, reliable, any inherent probs? I can pick up all three for $400. Thanks

 

[Chinewalker]

Grab 'em! The Stinger 75 was a mid-1970s-early 1980s model. I've got a 1980 with the checkered flag hood. Love it! Had it for 20 some years now, rebuilt it when I bought it in the mid 1990s with fresh bores, new pistons, rings, carb kits, water pump, etc. Other than replacing the water pump couple times for periodic maintenance, and having a power pack go on me, it's been trouble free. Oh, and I did have to replace the trim solenoid once as the old one got corrosion in it (transom mounted solenoid box got damp).

The OMC 3-cylinders are solid design, with the 75 hp, 49 cube models being among my favorites. 1978 & up gets you newer style power trim, or the ability to add it if desired. The mid 1980s era 56-cubers had some issues with cooling the block properly, but I believe they got the issues worked out with some updates.

Bottom line, if the complete motor is basically healthy (good compression across the board, no water in the lower unit), then go ahead and put carb kits, hoses, water pump into it and run it!

 

[jimmbo]

The 49.7 cu in 75hp is a good engine, with a couple of things to keep in mind. It is not the best choice for heavy boats as it is weaker in low rpm torque than the 70hp of the same displacement. It was designed for and does very well on light high performance boats. Propping is more critical than on the 70hp as the 75 makes its horsepower at a higher rpm 5500 vs. 5000, and has a narrower WOT range either 5200/5300 - 5800 vs. the 70hp of 4500 - 5500. The long shaft motors had the same gear case and gear ratio as the 70hp, while the short shaft engines had a smaller gear case and and a gear ratio intended for lighter boats. The engine may have marketed to comply with certain racing regulations. Reliability should be like any other OMC Looper, longevity might be a little shorter as the it is putting out more horsepower. 1.5 hp/cubic inch in a consumer motor was pretty much the line for smooth running easy going engines. I think that was the highest hp/cubic inch OMC ever did in a non competition specific engine. I just think they do best on lightweight hulls. Others options may vary.

 

[Keyboardman]

No Title

Thanks for the responses! I'm thinking of putting it on my old 1974 15' tri hull to replace the Johnson 50 that's on it now.

 

[Chinewalker]

As long as the boat isn't waterlogged, it should do well. As Jimmbo pointed out, propping is important. Mine spins abou 5900 with just me in the boat - a 15-ft Starcraft. Does about 41mph.

 

[Keyboardman]

Checked out the engines today. Compression on the best one is 125 in all three cyls. It is a 1976 model. Acceptable numbers??

 

[ezmobee]

Yes!