Offshoreonly.com - Am I propped wrong??

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Quote:

Originally Posted by astar77350 (Post 3200774)

Sorry for my ignorance but when you say cup, what are you referring too?

The blades are concave, like a bowl, some props have more cup than others.

Gotcha, that makes sense now, well I will keep u guys updated on my trials.

Quote:

Originally Posted by astar77350 (Post 3200388)

The brand is a mercury marine laser II. The number on the side is 48-16546 21p. Not sure of the diameter maybe these numbers will help.

As Rchevelle stated that is a smaller diameter prop. Look for a 21 Mirage Plus or similar.

Difference between Mirage and Mirage Plus????

Quote:

Originally Posted by Powerquest_Baby!! (Post 3196290)

Im guessing a 21P Mirage Plus too. Your operating range is 4600 to 5000 RPM with a mag motor. You will probably gain about 600 RPM with the 21P which should put you around 4700 and in your powerband.

--Right now your damaging your engine by running it at such a low RPM vs what it was designed to perform at. I would change props as soon as possible.

Very new to this boating stuff. How am I hurting the engine by running at lower RPM? I would think lower RPM is easier on the motor ...not harder. Enlighten me ...please.

Also ....what temp should this motor be running at? Right now it running at 140 /150 ...which I think is cool but my mechanic said leave it alone. Good or bad?