1971 Evinrude 100hp questions

[dstom]

Thanks to many of you, I have been able to get this oldie running again (after being idle for 10years!).

Anyway, this afternoon, I took the old boy for a spin, and decided to see what she had left in her. At full throttle, the tachometer barely got to 4000 rpm. It actually stayed around the 3800-3900 mark most of the time. (but I had fun anyway).

So the questions are--
1) What should the WOT rpm be on this engine?
2) Which would you recommend doing first-
a)new (or refurnished) prop?
b) rebuild the carbs?
or c) double check the timing?

I mention the prop because I had been using a four blade plastic prop, but it got banged up, so I am using my "get home" prop.

Thanks for any advice!!

PS- the boat is a 16" runabout (Bell Bouy, of the same vintage)

 

[oldcatamount]

Re: 1971 Evinrude 100hp questions

After sitting for 10 years, a carb cleaning would be the first thing I would do. Since the motor is consistant at 3800+, I would say the ignition is ok but, it sounds like a fuel issue to me. Not sure about the prop, but you should research that as it will effect rpm like you said. The max rpm should be 5k (or a lttle over). That's a good motor and worth your efforts.