I posted a thread yesterday about some issues I was having with my "new" 84 70hp Johnson. Basically, under WOT it would die out when more than 2 people were in the boat and I also had a fuel leak when the engine was tilted upwards.
Last night I took the air cover off to inspect the carbs and was amazed and dumbfounded at what I found:
I guess someone did some work on the carb at some point and forgot to put the 2 front screws back for the "top carb". Where the gasket is located between the air chamber and bottom "reservoir" on the carb, there is supposed to be 4 screws for each of the 3 "individual carbs"(terminology?), the top one only had 2 so when the motor was titlted, gas would leak out at a very constant pace where the gaskets is. I could actually squeeze the carb back together with my bare hands and see the gap closing where there was no screws, insane.
Needless to say I immediately picked up the correct replacement screws and put them on. I then put everything back together and titlted the motor, no more leak!
I thought the leak and dying under WOT might be 2 seperate issues but seems to be the same, which makes me very happy. It was getting late when I finished up so I didn't get the chance to drop in the water and try it out yet. I'll be doing so later tonight...
In the meantime, how much affect do you think this had on performance? It seemed fine when I was by myself but I couldn't really compare to anything so it's hard to say. I only took it out twice since I bought it and only really noticed it was struggling the last day when we had 5 people in the boat. I also went through 1/2 tank in 30mins so I imagine that gas was shooting out of the top carb like crazy.
Could this have damaged the carb at all?(High flow jet?) Everything seemed fine visually, it was clean and the valves were lined up ok. The engine also starts right up and idles smoothly. I guess my question is: To someone not too familiar, could it seem to be running ok on just 2 1/2 cylinders? I'm not sure how much performance could be lost with an issue like mine.
Thank you
Last night I took the air cover off to inspect the carbs and was amazed and dumbfounded at what I found:
I guess someone did some work on the carb at some point and forgot to put the 2 front screws back for the "top carb". Where the gasket is located between the air chamber and bottom "reservoir" on the carb, there is supposed to be 4 screws for each of the 3 "individual carbs"(terminology?), the top one only had 2 so when the motor was titlted, gas would leak out at a very constant pace where the gaskets is. I could actually squeeze the carb back together with my bare hands and see the gap closing where there was no screws, insane.
Needless to say I immediately picked up the correct replacement screws and put them on. I then put everything back together and titlted the motor, no more leak!
I thought the leak and dying under WOT might be 2 seperate issues but seems to be the same, which makes me very happy. It was getting late when I finished up so I didn't get the chance to drop in the water and try it out yet. I'll be doing so later tonight...
In the meantime, how much affect do you think this had on performance? It seemed fine when I was by myself but I couldn't really compare to anything so it's hard to say. I only took it out twice since I bought it and only really noticed it was struggling the last day when we had 5 people in the boat. I also went through 1/2 tank in 30mins so I imagine that gas was shooting out of the top carb like crazy.
Could this have damaged the carb at all?(High flow jet?) Everything seemed fine visually, it was clean and the valves were lined up ok. The engine also starts right up and idles smoothly. I guess my question is: To someone not too familiar, could it seem to be running ok on just 2 1/2 cylinders? I'm not sure how much performance could be lost with an issue like mine.
Thank you
