I have a Yamaha 89 70hp outboard. I was out cruising on the water and my engine died on me. It started back up fine, got it back up on plane and 10 seconds later it died again. I was able to run it a little over idle speed to get it back to the launch, but it was running real rough. I had a hard time getting it into gear without it stalling out on me. It was idling at a rough 500 rpm's. I immediately thought fuel problems. So I replaced the diaphrams and gaskets in the fuel pump, hooked it up to the earmuffs and it runs good, but obviously cant put it under a load yet.
I was doing a little more troubleshooting and checked the spark plugs. 2 of them looked good and brown and the other had a thin layer of black carbon all over it. So I fired up the engine again and took the plug wire off from that cylinder and nothing happened. took it off the other 2 and it almost died. I checked the spark for all 3 and they all looked good. I switched coils anyways and it did nothing. I'm thinking that cylinder may not be getting gas so I broke down the carb and gave it a good cleaning. All jets are clear and everything looks very clean. Put it back on and i'm still having the same problems. Does anyone have any suggestions? I dont really know what else it could be at this point. Don't know if this is related to the problem I was experiencing on the water or not, but thats why I included it in this post. Any help would be greatly appreciated. Thank you in advance.
I was doing a little more troubleshooting and checked the spark plugs. 2 of them looked good and brown and the other had a thin layer of black carbon all over it. So I fired up the engine again and took the plug wire off from that cylinder and nothing happened. took it off the other 2 and it almost died. I checked the spark for all 3 and they all looked good. I switched coils anyways and it did nothing. I'm thinking that cylinder may not be getting gas so I broke down the carb and gave it a good cleaning. All jets are clear and everything looks very clean. Put it back on and i'm still having the same problems. Does anyone have any suggestions? I dont really know what else it could be at this point. Don't know if this is related to the problem I was experiencing on the water or not, but thats why I included it in this post. Any help would be greatly appreciated. Thank you in advance.