1984 50hp Evinrue top plug fouls???

[Silvertip]

It is not likely that motor had its horsepower increased by 50%. If you suspect a bad plug, swap them. I doubt thats the problem. Start with a compression check. If that's ok, do a spark check. It spark is ok, move to the fuel system. Check fuel flow. If pump is ok, Remove carbs, disassemble them, thoroughly clean all passages and blow out with compressed air. Reassemble them with new kits. If the engine has fresh fuel, clean carbs, good spark and good compression it should run.

 

[junkmail@180iq.net]

1984 50hp Evinrue top plug fouls???

I don't know alot about boats, I have inherited one from my farther-inlaw and I need to get it running right to sell it.<br />After about 2-3 minutes of running with fresh gas at 50:1 and new plugs it starts backfiring. The top plug is dry and black and the bottom is clean with a little fuel on it. the motor hasn't been ran in 2 years and it fired right up. It was rebuilt about 4 years ago and taken to (from what I was told) 75hp. I'm not sure were to start. <br /><br />I have been around snowmobiles quit abit and my instincs tells me it's 1 of 3 or 4 things. <br /><br />1. Plug wire (it seem fine)<br />2. Coil<br />3. Gummed carb<br />4. Bad new plug (it happens but not likely)<br /><br />Anyone with experience with these motors that can help me, thank you in advance.