Today I sat out to do some catfishing, and boy did I have a experience....
I had went downstream about 10 miles or so to a little branch off the river to a little 'honey hole' of mine and my motor ran fine. I sat and fished for about 2 hours with no luck, so I decided I'd head downstream a bit further to another favorite spot of mine. I noticed the motor running a little rough but it soon smoothed out. I went down and fished for a few more hours and was getting ready to head back to the boat ramp, when I noticed my boat seemed to be hitting on only once cylinder. I stopped, pulled the hood and swapped in two brand new Champion spark plugs (QL77JC4 gapped at .030). When I started it up, it ran fine for about 2 miles then it seemed to drop a cylinder again. I pulled the lower plug and it was sopping wet with fuel so I swapped in ANOTHER brand new plug and headed off again. It ran fine for about 10 seconds then dropped the cylinder again.
I pulled the plugs and the lower cylinders plug was sopping wet with fuel. The top was a nice brownish color and dry. I pulled the plug wire on the lower cylinder and stuck a screwdriver down into it and started the engine...it had nice blue spark, as did the top cylinder. After troubleshooting this thing for about 1 hr (swapping plug wires, putting ice on the coil to cool it down, etc etc) I decided to limp back upstream to the boat ramp. At this point I had about 3 gallons of fuel. I went about 4 miles upstream and the motor picked up and ran fine for about 8 seconds...then it died... To my avail the fuel tank was DRY. Luckliy I was about a mile from a gas station so I trolled over to the bank and walked up and got 5gals of fuel. I got back in the boat and started it up to the same old junk. I wondered why the engine had picked up when it was running out of fuel so I reached back and unsnapped the fuel line. After about 3 seconds the engine picked up and hauled butt until the carb started running out of fuel. I did this about 10 times then I just started kinking the fuel line to keep the engine at WOT.
1990 Johnson 20hp. Tank is old but is clean on the inside with new fuel lines and primer bulb. I also replaced the engines fuel line and the connector that joins the line to the engine. I rebuilt the carb about 2 years ago and have ran the fuel out everytime I'm done fishing ever since.
Sorry for the book guys, but I tried to disclose as much info as possible. Thank you for any help!
sounds as if you should check your fuel pump as it works off the pulse from the lower cylinder..3 gals. of gas in 4 miles, it has to be pumping it straight into the lower cylinder and out the exhaust ports