Another Prop Question/advice

[70ss496]

I've asked before and everyone thought I'd pick up a lot in the cooler weather. The boat is a 1990 184DC. It has a 175 Yamaha on it. I don't know anything about the prop except is says 25M on it. I'm assuming it's a Yamaha 25M?? The best RPM I can get is 5,200 and the occasional flicker to 5300(Yamaha digital gauges). This was in 42 degree weather with a water temp of around 54 degrees. Just me in it, and a 1/2 of tank of gas. I don't have a GPS but digital speedo was 64 mph. I know it's probably not accurate but it's all I have for now.

So my question is what should I do for a new prop this winter to get more RPM's. Everyone I've talked to says that motor should turn 5600-5800. Tempest Plus? Stay with Yamaha but smaller? Or another 500 rpm won't make any difference in speed? Looking for advice suggestions on what prop. Thanks for the help! Matt

[pmgoffjr]

That M is a very good prop, no need to replace it.

That hull/motor will respond to a 6" jack plate very well, you'll find some new rpms and a good amount of speed when you install that.

Then...if it's still not pumping out what you want, you can have your prop tweaked to give whatever results you want.

[70ss496]

Thanks Pat, the prop has a couple nicks in the edge of it. Can they check to make sure it's put in spec when they fix that? Also, you recommended the rapid jack, correct? Does anyone make them with the Champ offset? Not really sure what that means?

Matt

[pmgoffjr]

Champ offset...they add a couple of degrees of positive trim at the plate, it's really not necessary with your yamaha, but it's very helpful with a mercury.