'72 Evinrude 100HP Carb Cleaning for tomorrow

[txboatman]

I have a 1972 Evinrude, and when I originally had it cleaned up and running last summer, I had the top speed up to about 35Mph, then slowly it has been getting worse and now to 20Mph. I cant even pull a tube anymore, so I figured I would clean the carbs today before a big day out tomorrow. Now I am unsure, what to do. Maybe, a bad float or gunk buildup in the carb? If I have to buy a float, where could I get one today? What do I cleanse the Carbs with and how? Any help would be appreciated. Thanks!

 

[tashasdaddy]

Re: '72 Evinrude 100HP Carb Cleaning for tomorrow

Ethanol and fuel lines
replace all fuel line with Alcohol resistant lines. Ethanol deteriorates, the rubber lines, then they start to sluff off on the inside, going directly to the carbs. Settling to the bottom of the bowl. Contaminating the carbs high speed jets. clean a rebuild carbs, flushing fuel line before connecting to carbs.


read the topics in the TOP SECRET FILE, 2nd thread in this forum.

 

[txboatman]

Re: '72 Evinrude 100HP Carb Cleaning for tomorrow

Does it sound like a carb problem? Since 10mph decrease over the last yr? How do I tell if the float is bad?

 

[tashasdaddy]

Re: '72 Evinrude 100HP Carb Cleaning for tomorrow

possibly, but i would check spark and compression first, using a $10 spark tester from auto parts store, set it as 1/2 inch gap, spark should jump that with a bright blue spark. using a screw in compression tester, you compression should be 100 psi or above, but the main thing is that the readings are with in 10 % of each other. this will tell you the health of you motor, before sinking parts into it.

 

[Boss Hawg]

Re: '72 Evinrude 100HP Carb Cleaning for tomorrow

Awwww- another last minute plea for help

"so I figured I would clean the carbs today before a big day out tomorrow"
Why not overhaul the carbs (cleaning dont usually cut it) say-- a week before the big outting You know your going to have to do it - Git-R-Dun

 

[txboatman]

Re: '72 Evinrude 100HP Carb Cleaning for tomorrow

I went and got new plugs. The compression was within 7% last time it was tested a few months ago... I will check again. What should the plugs gap be set at?