1977 75hp Johnson Stinger

[Keith Carlson]

My 77-75hp Stinger model #75ELR77S runs very rough at low speeds. Carbs have beed cleaned and replaced plugs. What needs to be done???

 

[Chinewalker]

Re: 1977 75hp Johnson Stinger

Hi 98Caddy,<br /> Exactly how did you clean the carbs? Were they removed, disassembled, soaked in carb cleaner, blown out with compressed air and then rebuilt with fresh carb kits? Pay special attention to the idle jet orifices for cleanliness. <br /> Is it running on all three cylinders at idle? A blown head gasket can be masked at higher speeds, but become apparent at idle. Any evidence of water on the plugs?<br />- Scott

 

[andys15]

Re: 1977 75hp Johnson Stinger

Had the same engine, same problem. Check the slow speed idle adjustment, I think that's what it's called. There's two needle valves on the carbs. One's for low speed, another for high speed.

 

[Keith Carlson]

Re: 1977 75hp Johnson Stinger

Originally posted by Chinewalker:<br /> Hi 98Caddy,<br /> Exactly how did you clean the carbs? Were they removed, disassembled, soaked in carb cleaner, blown out with compressed air and then rebuilt with fresh carb kits? Pay special attention to the idle jet orifices for cleanliness. <br /> Is it running on all three cylinders at idle? A blown head gasket can be masked at higher speeds, but become apparent at idle. Any evidence of water on the plugs?<br />- Scott

 

[Keith Carlson]

Re: 1977 75hp Johnson Stinger

Hello Scott, Carbs were cleaned as you said. I'll have to check compression, no sign of water though. Thanks

 

[WillyBWright]

Re: 1977 75hp Johnson Stinger

I've replaced a lot of throttle shafts in those over the years. They wear and allow air in thru the bore that holds them making them idle badly and run lean at high speed.

 

[aka_therebel]

Re: 1977 75hp Johnson Stinger

I have the same engine, rough idle, horrible hesitation when advancing throttle, lacks power big time. I can open throttle WO and it can take 2 minutes to get a 15' checkmate on plane. When I shut it down there is gas/oil running out of the motor compartment. I have tried so many things, Im ready to junk it...lol

 

[NelsonPoulin]

Re: 1977 75hp Johnson Stinger

My 77-75hp Stinger model #75ELR77S runs very rough at low speeds. Carbs have beed cleaned and replaced plugs. What needs to be done???

your probleme is sample,,,,changer intak valve in plastic,this valve is in the plate of intake,after a couple of years,,,the plastic is so soft and not work correctly,sometime,is make a bakedraft in carbs at idle ,its your probleme ;o)
sorry for my anglish,i need pratice ;o)