Re: Prop for 1977 15hp Evinrude 2 cycle
No idea if it is the original prop. Bought it earlier last year from my mom's neighbor who bought it from someone else about 10 years earlier. Who knows but it definitely could use replacing. Thinking the 4 blade 8" and maybe a stainless 3 blade 10". I've heard that stainless is a waste on smaller motors and conversely that it can be life changing LOL! The Solas SS is only $40-$50 more than aluminum, I'm willing to gamble that much for my WOT run around the reservoir not likely to run in to anything prop.
THANKS FOR ALL YOUR HELP!
Let's 1st get the misinformation straightened out.
New that motor made 120-125psiMax with a good gauge. We sold more than enough to know.
Once the compression drops much below 100, it can be hard starting and not idle low. How's yours'?
You probably have a bad gauge. If the shraeder valve is in the wrong place, you'll get low readings.
If your 1st pull is yielding a quick 65psi, that's good. suspect gauge.
A decarb or 2 is great. Once the ports get carbon on them, you can lose considerable power and of course rings.
From your picture,
your carb throttle plate was not fully open. Now when you pulled out the cam follower by hand, it was opened too much, which begins to close it.
The throttle plate is correctly fully opened, when the roll pin is vertical to the motor. As you are aware, the 2 throttle cam bolts allow, low speed link and sync, and full throttle opening.
Onto the props. Some of the props i have seen for those, are horribly thick and poorly shaped.
If you go with the SS Saturn, we have found a drop in pitch is needed as all the ones we've seen are cupped - even the small ones. And I believe slightly progressive pitched.
I think they are great Props and a bargain at $127 and frankly may do it all for you.
With cup, it can be mounted higher and trimmed out further. Nice thin blades, slight progressive pitch - quick with best top end.
I'm going to say go with the 9" and 23mph light, no fin, trimmed. Don't mark it up - iboats will accept an
AS NEW - return.
Just an fyi - the
150/200rpm per inch change in pitch is useless when dealing with small pitch sizes, because the percentage of pitch changes so drastically, the change can easily be 5-800rpm change.
For the shallows, you can run the motor trimmed down (mounted high) - maybe add the fin...
Longer trips trim out no fin, still motor mounted high.
For others in your situation, please post back with results...no debt of gratitude, rather debt of closing out your post.LOL
