Problem Starting 1986 90 HP Outboard

[PapaGazi]

I'm new to the boating world and just recently acquired an older boat from a gentleman. It is a 1967 Cobia Cuddy Cabin with a 1986 90HP Evinrude. When I picked up the boat, the gentleman got the motor running with no problem. It did idle rough and he suggested doing a carburetor rebuild. When I got the boat to my house, I tried to fire up the motor to run some seafoam treatment, but I cant get the motor to fire up. I got it to start but it stalled out after about 30 seconds. The guy told me I can use Seafoam Spray directly into the carbs to get it to fire up long enough for the treated fuel to be cycled into the motor.. is this a good idea? Will it help get the motor running or do I need to do the rebuild on the carburetor? Like I said, I'm new to boating so dont know too much as far as mechanics are concerned, however I'm trying to learn. Any help would be greatly appreciated.

[boats.net]

You need to remove and rebuild the carburetors. Don't waste your time with additives, if the carbs are gummed up enought to not allow it to run, additives will not help.

[PapaGazi]

Thanks for the info. But now I'm having another problem. I did the carb rebuild and she fired right up, no hesitation at all. I took her out on the water for a trial run to make sure everything was good. Ran beautifully the first day, lots of power, no stutter or anything. The 2nd day, she ran great again until I shut her down and anchored for about an hour. When I tried to fire her back up, she wouldn't fire. Starter, choke, everything engages as it should, she turns over, just wont start. I'm guessing maybe a spark issue? Replace plugs and wires just to be sure everything is new and operating? If so, I know what plugs I need for it, but I couldn't find any info on the wires. Would a basic set from AutoZone work, or are these something you can only find at a marine shop? Again, I appreciate all the help.

[boats.net]

Did you check and verify you are loosing spark. If you are, check your safety switches. The following link is for the factory replacement spark plug wires, you require 4

0582365 OMC SP PLUG LEAD AY $10.47

[hydrex]

If you found a lot of varnish and crud in the carbs, it's likely the fuel hoses on the motor are full of crud. I rebuilt the carbs on my 1982 90 hp and they filled back up with varnish and crud from the fuel lines, even though I have a new tank and new fuel line to the motor. Also , if you have not already, clean and rebuild the fuel pump. If it's like my '82, it has pretty simple carbs, but the least bit of old varnish/crap will plug up the works. Make sure you have the correct plugs as well, mine had the wrong ones, when I bought it. Once I got mine running right, it purrs like a kitten.