Hey guys,
I have a 1988 2 stroke Johnson 40hp engine, runs like a top. Recommended rpm is 4500 to 5500. It currently runs at 5440 rpm (properly trimmed) with a 10.125 x 13 Turning Point prop. This pushes my 1988 Traveler aluminum boat @ 31 mph. I am happy with this configuration. I also have a Solas 12.5 x 15 that came with the boat, but have no data on this prop. I changed it before I put the tach on... but based on current info, this would drop rpm drastically.
Now, because the rpm rating is a 1000 rpm area, is it better for the engine to bring the rpm closer to 5000, which falls in the middle of the rated rpm, or does it really matter... just as long as it stays in the rated area? This boat is fairly new to me and I am wanting to get it right.
Thanks for any info /advice.
foots
I have a 1988 2 stroke Johnson 40hp engine, runs like a top. Recommended rpm is 4500 to 5500. It currently runs at 5440 rpm (properly trimmed) with a 10.125 x 13 Turning Point prop. This pushes my 1988 Traveler aluminum boat @ 31 mph. I am happy with this configuration. I also have a Solas 12.5 x 15 that came with the boat, but have no data on this prop. I changed it before I put the tach on... but based on current info, this would drop rpm drastically.
Now, because the rpm rating is a 1000 rpm area, is it better for the engine to bring the rpm closer to 5000, which falls in the middle of the rated rpm, or does it really matter... just as long as it stays in the rated area? This boat is fairly new to me and I am wanting to get it right.
Thanks for any info /advice.
foots