3.0 Mercrusier in 1997 17ft Regal

[ndieagle65]

Need new Prop. Stock prob was 3 blade aluminum, went to a four blade aluminum couple years ago for better hole shot pulling a skier. Not happy with top end of four blade or high RPMs (around 4500 or that is about as high as I will take it) at about 30 mph.
Would stainless make difference? I am not sure of dia or pitch of either prop. 3 blade doesnt day and havent looked at 4 blade yet. Any recommendations?

 

[Robbabob]

Re: 3.0 Mercrusier in 1997 17ft Regal

Welcome to the forum!

Before we can even come close to providing a smart answer, we need some essential data from you. You gave some of the information, but this list below is found in a sticky at the top of the prop forum page.

ESSENTIAL DATA REQUIRED
When posting a question about propellers, you cannot get a reasonable answer unless you provide the following information in your post: Items 1-4 are essential for meaningful response to most questions.
1) Performance issue you are trying to correct.
2) Current prop manufacturer, model, aluminum or stainless as a minimum.
3) Current prop diameter and pitch (required).
4) Wide open throttle RPM and speed with an average load (very helpful)
5) Engine/drive make, model, year, and HP
6) Boat make model, year, length and weight

FYI - Properly sized, the 4-blade will always give better hole shot and lack the top end speed. A 3-blade is always your best all-around prop if you are going to stay with a single prop and try to enjoy all aspects of boating. Going with SS is better when your HP is plenty; possible the 3.0L in a 17' Regal would benefit from the SS. If you have concerns about large rocks or fixed stumps coming into contact with the prop, then stay with aluminum.

Fill in the information above and we'll be able to help you out.

Good Luck!

 

[steelespike]

Re: 3.0 Mercrusier in 1997 17ft Regal

Your prop size will be on the barrel or under the prop nut.
Typically a 3.0 in a 17 ft boat would run over 40 mph.Hopefully your lack of speed
is because of a poor prop selection.

 

[ndieagle65]

Re: 3.0 Mercrusier in 1997 17ft Regal

Okay went and looked. Current prop is 14.25x19 4 blade aluminum Solas. Old prop was weird numbers 48 78120 A40 19P 3-blade aluminum. I know I had more top end with three blade. But maybe little better pulling up skier with 4 blade not sure. But 4 blade did seem to raise RPMs a little for same speeds. What about those new 5 blade mercury blades? Or would a stainless 3 blade be better? I know I ocasionally nick my prop on debris and bottom at lake.

 

[steelespike]

Re: 3.0 Mercrusier in 1997 17ft Regal

The props were esentially the same size. That is a Mercury number but I can't decifer it ,someone should be along that can.It is a 19" pitch thats the key number.
Is the 30 mph by a speedo or gps?If it is reasonably accurate your missing a hole lot of speed.
With a 19" the boat should make 40 or more Some boats in that size/hp have been reported to do 40 45 mph and run up to a 23" pitch.Motor is rated for 4,600,at 4500 rpm you should be close to 40. It appears either your tach is wrong or the speedo is wrong. A 19 probably would struggle
a little with water sports especially if your carrying a gang.Usually when going to a 4 blade it is suggested to drop an inch in pitch to maintain rpm.That would depend on the performance with a 3 blade.I can't speak for the 5 blade except as you add blades you add drag.And I think the 5 is intended for a more powerful motor.Its important to move your passengers around to avoid too much in the stern also trim in/down for hole shot.
A stainless could help a little at about 3 times the cost.The bottom line is top end and hole shot don't go together.

 

[honeys money]

Re: 3.0 Mercrusier in 1997 17ft Regal

I pull wake boards, air chairs, and skis, most of the time with 4 or 5 ppl in the boat, I have a 19"X14.5" and a 23"X14.25, the 23 is for my wife and I to just cruise at about 30MPH, but the 19 is for pulling ppl on toys. The 23" will run about 46MPH trimed out at 4600 RPM and the 19 will go about 43 or 45 at 5,000. I know ppl on here don't like wale-tails, but I do, lowered plane speed and hole shot is a lot better with a load, and when trimed up it is out of the water.