1999 Sea Ray 180BR - 4 blade performance?

[Dogsluvtrux]

After an 8 year hiatus from the water mostly due to children, I bought a "new" boat last week. After lurking here and soaking up a lot of knowledge, I ordered a new 19p Solas 4 blade prop to replace the 23p 3 blade that was on the boat.

Went to the lake today and ran the boat with the old prop and it was a bit of a dog....a little under 7 secs to plane, 43 mph at 4100 rpm (all based on boat's speedo and tach). Sea Ray specs say it should have been a 21p prop on the boat from factory and I dropped to 19p because I went to a 4 blade vs 3. Got home from the lake, and FedEx had delivered my new prop! Grabbed a beer and put it on the boat. It's an hour back to the lake, so won't go tonight, tomorrow we have thunder storms in the area.....my question is this, what can I expect out of the new prop? I'm fine losing top end, 40 mph is ridiculous on Clinton Lake, I just want it to jump on plane better....

 

[dcarver]

Re: 1999 Sea Ray 180BR - 4 blade performance?

Going from a 23p to a 19 4 blade will be a huge decrease in the time it takes you to plane. I went from a 19p 3 blade to a 17p 4blade and it was night and day. I have an 18ft bow rider with the 4.3 merc. so I'm guessing our boats are similar. You will definitely love it. I hit 40 with the 17p 4 blade. Let me know what you get with the 19p. Also from what I'm gathering, the 4 blade spins faster because of more blades so supposedly you can go up in pitch. So a 21p 4 blade would be similar to a 19p 3 blade as far as overall performance

 

[SkiDad]

Re: 1999 Sea Ray 180BR - 4 blade performance?

I'm going to say about 4800 rpm and 39-40 mph and about 3.5 seconds to plane - just my guess

 

[Dogsluvtrux]

Re: 1999 Sea Ray 180BR - 4 blade performance?

Going from a 23p to a 19 4 blade will be a huge decrease in the time it takes you to plane. I went from a 19p 3 blade to a 17p 4blade and it was night and day. I have an 18ft bow rider with the 4.3 merc. so I'm guessing our boats are similar. You will definitely love it. I hit 40 with the 17p 4 blade. Let me know what you get with the 19p. Also from what I'm gathering, the 4 blade spins faster because of more blades so supposedly you can go up in pitch. So a 21p 4 blade would be similar to a 19p 3 blade as far as overall performance

I thought it went the other way....A 21p was on the boat from the factory so I dropped to a 19p four blade......did I get the wrong prop?

 

[jestor68]

Re: 1999 Sea Ray 180BR - 4 blade performance?

Based on your rpm with the 23", the 4 blade 19" prop should rip out of the hole and get about 4800 rpm.

It should make a good prop for water sports.

 

[dcarver]

Re: 1999 Sea Ray 180BR - 4 blade performance?

Doing a little more investigating, 4 blade may be a tad slower so a drop in 1 degree of pitch is required for the same performance as a 3 blade. So 19p 4 blade should be the one

 

[Starcraft5834]

Re: 1999 Sea Ray 180BR - 4 blade performance?

The 4 blade you selected will will notice a huge increase in hole shot, you will get on plain in about 1/2 the time..maintain plain at slower speed, increase fuel effeciency, water sports a breeze, slow speed steering improves greatly, the advantages of a 4 blade over a 3 blade are about 6-1... if your ok with losing 1-2 mhp top end (which most people are), you will love it!!!

 

[Dogsluvtrux]

Re: 1999 Sea Ray 180BR - 4 blade performance?

Excellent! Just what I wanted to hear....got a call today the swim platform is being built tomorrow, new prop is on the boat, picked up a spare 21p 3 blade used from the Prop Doc....just need it to be 30 degrees warmer and head back to the lake!!

 

[Dogsluvtrux]

It's been awhile, but have done a lot of testing. 4 blade prop was a HUGE improvement! Loaded boat with two adults and two kids, runs 39 mph per gps, jumps onto plane in less than 4 seconds and stays on plane down to 13 mph. Biggest issue I have one is walking at low speed and I need to adjust the skeg to get it to track straight. I would like to add either trim tabs or a hydrofoil to add a little more stern lift......thoughts?

 

[steelespike]

Are you talking about no wake speed wander?
Still on plane at 13 mph and you want more?
Both the foil and tabs will probably cost a little speed and fuel.

 

[Dogsluvtrux]

Yes....it wanders at no wake speed and on plane i have the wheel turned to the left approximately 15 degrees or so to run straight.

 

[jestor68]

Yes....it wanders at no wake speed and on plane i have the wheel turned to the left approximately 15 degrees or so to run straight.

Do you mean that you have to hold a constant pressure on the steering wheel to travel straight; or the boat wants to turn right?

If so, then you adjust the trim tab anode on the stern drive in the same direction that the boat wants to turn.