Got a Loaner Merc Inertia 17P Prop?

[Capt Terry]

Running a '76 20' Seafari with a 2012 ETEC 150 HO in SC for watersports with a High Five 13.5" x 17P which works well in helping me overcome the wakeboard speed swings I got with the ETEC. (Yeah the engine A/V plate looks good per Skippertee). However, this is not a great cruise at any speed prop, unless I use my PerfectPass speed control. I'd like a good cruising and spare prop. I have tried 4 or 5 other props, but none have gotten me to the 5500-5600 recommended WOT RPM like the High Five has. Ken at Propgods suggested a Merc Inertia 17P prop. Wondered if any CSC folks might have one I might borrow to try?

[McGillicuddy]

Sorry Capt., ain't got an inertia laying around. Run the Powertech MQS4 by the prop God. 14.5 by 16 or 17. Can't help but think it would be a perfect cruise and tow wheel.

Same shape as Mercs classic black max in stainless and has 4 blade option.

Great stern lift, great holeshot, great cruise, easy to turn.

[Capt Terry]

McGillicudy-
Thx for remark. I tried Bushwacker's Powertech 4B 15"x15P. It performed pretty well, but was short on both RPM & Speed versus my High Five:
POWERTECH, plus 5 degrees trim, DAY1 5340 38
POWERTECH, plus 6 degrees trim, DAY1 5380 38.5

HIGH FIVE, plus 5 degrees trim, DAY1 5630 40.7
HIGH FIVE, plus 6 degrees trim, DAY1 5680 40.2

CYCLONE, plus 5 degrees trim, DAY2 5280 40.8
CYCLONE, plus 6 degrees trim, DAY2 5330 40.8

My old Merc 3B Black Diamond 14.5"x17P was looking pretty good until it cavitated real bad during a hot hole shot. My dealer provided Cyclone was pretty efficient & performed well, but still short on WOT RPM (it worked perfectly for Bushwacker). Note: At beyond 6 degrees trim all were virtually unsteerable.

[Cutiger]

I might. Headed to Atlanta today but I'll look tomorrow when I get home. I'm pretty positive they're 17P but not sure if enertia or mirage or what. They're on a pair of 150 Optis I just bought. Not on the boat yet and it'll be a while so welcome to test it.

[Capt Terry]

Cutiger-
Thanks for response. I live just south of Greenville, SC. But will be headed to Fla in mid August for hopefully a short trip. I could probably test the prop in late August if it all works out.

[McGillicuddy]

Originally Posted by Capt Terry

McGillicudy-
Thx for remark. I tried Bushwacker's Powertech 4B 15"x15P. It performed pretty well, but was short on both RPM & Speed versus my High Five:
POWERTECH, plus 5 degrees trim, DAY1 5340 38
POWERTECH, plus 6 degrees trim, DAY1 5380 38.5

HIGH FIVE, plus 5 degrees trim, DAY1 5630 40.7
HIGH FIVE, plus 6 degrees trim, DAY1 5680 40.2

CYCLONE, plus 5 degrees trim, DAY2 5280 40.8
CYCLONE, plus 6 degrees trim, DAY2 5330 40.8

My old Merc 3B Black Diamond 14.5"x17P was looking pretty good until it cavitated real bad during a hot hole shot. My dealer provided Cyclone was pretty efficient & performed well, but still short on WOT RPM (it worked perfectly for Bushwacker). Note: At beyond 6 degrees trim all were virtually unsteerable.

Well the Enertia Eco has been hailed as the magic prop...

Interesting. Were all of those props of same patch and diameter?

I believe Bushwackers PT Prop is an ELE4 model, very different shape with more cup than the MQS making it more difficult to spin.

The MQS4 is a SS 4-blade, comparable to the Black Max but designed with towing sports in mind. I think they nicknamed it SkiMax or something like that. I think your required trim angle puts a lot of undue pressure on the prop and combined with the extra force of a wake boarder maybe lending some effect to the cavitation you've experienced. Sounds like you'll need an easy to turn wheel and a favorable rake. You engineers are gonna have to figure that one out

Good luck with the Enertia.

[Capt Terry]

Sorry McGillicuddy, thought I had included the prop characteristics of the tested props. Here they are:
HIGH FIVE Stainless 5B 13.5" X 17"P
5 degrees trim, DAY1 5630 40.7
6 degrees trim, DAY1 5680 40.2

POWERTECH 4B 15" X 15"P
5 degrees trim, DAY1 5340 38
6 degrees trim, DAY1 5380 38.5

CYCLONE Stainless 4B 14.5" X 15"P
5 degrees trim, DAY2 5280 40.8
6 degrees trim, DAY2 5330 40.8

Black Diamond Aluminum 3B 14.5" X 17"P
5 degrees trim, DAY3 5420 41.1
6 degrees trim, DAY3 5530 40.1

Vortex Aluminum 4B 14.0" X 18"P
0 degrees trim 5250 36.3
5 degrees trim 5390 38.3

Recorded RPM and speed were digital from a GPS PerfectPass gage. I can set the desired PerfectPass RPM which holds steady within about +/-20, then record the attained mean speed at that trim angle.

My typical operation is between 0 and 5 degrees trim, at 6 it starts getting hard to steer. Sometimes start trimmed down for the accel particularly for slalom and footing, then trim up after planed out. All tests were similar conditions and all without towing anyone. Sometimes flatter water than other days. The Black Diamond cavitation (don't remember trim angle) also not towing anyone. Once again for my routine operation at watersports, the High Five is good. The Cyclone might have been a good cruise prop if it were tweaked a little with a smaller diameter or lower pitch to increase the WOT RPM. Cyclone WOT speed was good, just not revving high enough.

[Bigshrimpin]

old enertia 17p is the prop you want IMO. I have one but it's on my boat now . . . If you want to wait until October I can mail it down if you cover postage. I would bet it's 3mph faster than the highfive (same pitch).

[Cutiger]

Mine are 17p Mirage Plus

[Capt Terry]

Cutiger-
Thanks for looking. Don't know anything about Mirage.