Can’t Figure out Prop ….

[DAMMREEL]

Hi all, first post. I have a 2001 Stingray 180LS with a Mercruiser 3.0 w an Alpha Gen 2. Average of 4 passenger equaling 550lbs. Rec and fishing use only, no towing / skiing. Looking to upgrade what looks to be the original prop. I checked all around the prop and can’t decipher what I have and only see some of the number where the nut is in place. Looking for either the same size or to improve getting in plane a little quicker but maintain as close to efficiency as possible.

I appreciate all feedback, thank you.

 

[Scott Danforth]

You need to know what you have and what RPM you currently get at WOT and fully trimmed.

Pull the prop and get the numbers

 

[Scott06]

View attachment 391366View attachment 391367

Hi all, first post. I have a 2001 Stingray 180LS with a Mercruiser 3.0 w an Alpha Gen 2. Average of 4 passenger equaling 550lbs. Rec and fishing use only, no towing / skiing. Looking to upgrade what looks to be the original prop. I checked all around the prop and can’t decipher what I have and only see some of the number where the nut is in place. Looking for either the same size or to improve getting in plane a little quicker but maintain as close to efficiency as possible.

I appreciate all feedback, thank you.

Cant read the numbers from here. You need to pull it off and wire brush the numbers- are there any numbers on the side of prop? Looks like it hasn't been off in a while? if so might be good to grease the splines and check the annode behind the prop.

As Scott outlines need to know your current WOT rpm. To get better holeshot you will want to go down in pitch and maybe get a 4 blade (with even lower pitch). Ideally need to know what pitch is on there now.

Your set up - 18 ft with a 3.0 is about as efficient as a boat gets. I used to run 4 blades on mine for same reason you mention, also found I got better stern lift and lower planning speed.

 

[airshot]

Some props are stamped on the sides of the hub and others are stamped on the end of the hub, top or bottom. Something like 15x13P. Have ran across a couple that just had a midel number stamped on them and you had to reference a chart. Most of the time the dia and pitch is what is stamped.

 

[DAMMREEL]

Well I was fortunate enough to find the booklet of the stingray line in 2001. Under performance, I found the OEM prop number used (D). So happy to find it. 14” X 23”. So if I want to go 4 blade, I would go 14” X 21”? Maintaining the efficiency but getting a better whole shot and quicker plane?

 

[Scott Danforth]

Well I was fortunate enough to find the booklet of the stingray line in 2001. Under performance, I found the OEM prop number used (D). So happy to find it. 14” X 23”. So if I want to go 4 blade, I would go 14” X 21”?

No way a 3.0 is spinning a 23p prop. or a 21p prop

 

[Scott06]

Well I was fortunate enough to find the booklet of the stingray line in 2001. Under performance, I found the OEM prop number used (D). So happy to find it. 14” X 23”. So if I want to go 4 blade, I would go 14” X 21”? Maintaining the efficiency but getting a better whole shot and quicker plane?View attachment 391476

Check what is on there now not the catalog, 23 doesn’t seem correct As my 3.0 was sluggish with a 19”…and we keep asking current wot rpm. This is key to deciding next prop. Do not try a different prop without establishing current wot rpm.

 

[airshot]

Before spending any hard earned money on a prop, go thru that engine and make sure she is running 100% !!
Saw many folks go thru prop trials only to find they had an engine issue...First thing I would check is compression...the 3.0 is noted for warping the head in the center. Not a hard fix, but will lower performance a lot !!

 

[Texasmark]

Well I was fortunate enough to find the booklet of the stingray line in 2001. Under performance, I found the OEM prop number used (D). So happy to find it. 14” X 23”. So if I want to go 4 blade, I would go 14” X 21”? Maintaining the efficiency but getting a better whole shot and quicker plane?View attachment 391476

Well I don't know what is on there but I agree with his thinking on dropping pitch when adding the 4th blade.

 

[airshot]

In my experience, we dropped up to 2" pitch when going to a 4 blade prop...

 

[Scott Danforth]

looking at the pic, looking at the corroded numbers.....looks like the numbers shown are 48-832828 which would be a 17P per the chart. which is what a 3.0 can spin. going to a 4-blade, I would drop down to a 15P.

 

[Scott06]

looking at the pic, looking at the corroded numbers.....looks like the numbers shown are 48-832828 which would be a 17P per the chart. which is what a 3.0 can spin. going to a 4-blade, I would drop down to a 15P.

On my sea ray 170/3.0 I used to run michigan vortex 4 blades- 16” for skiing, 18” for everything else. both really worked nice for the price.

 

[JimS123]

My 190 Stingray with the 3.0 turned a 21" cupped SS prop and that would provide the spec max rpm at WOT.

 

[QBhoy]

No way a 3.0 is spinning a 23p prop. or a 21p prop

I’d normally agree there. But I actually happen to know. Or did know a 18ft stingray that had a 3.0 and turned a 23” laser 2 and before that a 23” black max ally. Ran well into the 40’s gps. 99% sure it was a 2.1 alpha or there abouts she had. Very slick and fast hull, some of them. Very lightly built too perhaps. Probably a rare instance of an example, but certainly there are plenty of generic light 17/18ft bowrider with 3.0 running 21”‘a quite commonly around here. Heavier built or a little larger examples with 19” often

 

[airshot]

My neighbor has a 21' Sylvan aluminum hull with a 140 hp 3.0 and turns a 21" pitch prop at about 42 mph at 4400 plus rpm. Not sure a 3.0 could handle a 23" pitch.

 

[Faztbullet]

I got a customer with lil SeaRay 18ft with 3.0 that turns 24 Turbo all day long.

 

[QBhoy]

I got a customer with lil SeaRay 18ft with 3.0 that turns 24 Turbo all day long.

Good to read I’m not the only witness to something close. That 18ft stingray ran the 23” very well.

 

[airshot]

I got a customer with lil SeaRay 18ft with 3.0 that turns 24 Turbo all day long.

Doesn't mean it is running proper RPM for the motor. We have a number of guys over proped at the local marina to get the most speed but not healthy for there motors

 

[mr 88]

All these comparisons without knowing what gear ratios might be in the outdrive are useless. Who knows if the OPs was swapped out or if his boat is waterlogged with 80 psi for compression numbers . As mentioned OP needs his RPMs # with appropriate load before anyone should be making recommendations based on his current props performance

 

[YellowT]

A bit late, and perhaps not helpful, but...

The OP's propeller has a Rubex "reusable" hub installed - probably a #102 kit. (The engine application, stamped number and lockdown hardware behind the prop nut are consistent.) If so, it's likely that this is a replacement prop.

The propeller is painted, so it may be an aluminum Rubex 3 or similar type.