odd prop size was on my horizon 180?

Toddely · **Posted:** Sat Jul 20, 2013 8:24 pm

Hey guys , I have a quick question I have been planning on getting a new prop for my Horizon 180 Rs, it has the 5.7 gl engine, i believe it is 215 hp. When I finally took a look at the prop it is a 4.25 x 23. I finally checked my max rps and its around 3850 - 3900 rpms. I believe this boat had an over pitched prop on it. I purchased a new Volvo Penta 14.3 x 21 prop today. The dealer believes the boat should run quicker and with a little more rpms as well, said it should actually be getting all the hp now. Whats your input on this info. Thanks again.

chefred112 · **Joined:** Tue Jul 05, 2011 3:03 pm **Posts:** 44

I believe it..3900 rpms is way low at wot

Surface Interval · **Posted:** Sun Jul 21, 2013 9:44 pm

Looking at the "Fast Facts" on the Four Wins web site the 14.25x23 prop is listed for this boat and engine package. Has the outdrive ever been reworked or switched? If so, you may have gotten a different gear ratio in the out drive. Is there another issue that is robbing power? I had a '95 190 with a Ford motor that had an exhaust flapper valve come loose and restrict the exhaust. Instead of the 4600 rpm top end it would struggle to reach 4000-4100rpm. Otherwise, the engine checked out fine. Trimmed out at top end I believe that engine should turn in the general area of 4400-4800rpm.

ric · **Posted:** Sun Jul 21, 2013 11:37 pm

Also is your max rpm with 6 people in the boat or just you?

deafwish · **Posted:** Sun Jul 21, 2013 11:51 pm

I have exactly the same boat/ engine combo and opted for a Solas 14 x 21 Amita 4 blade.
The boat has much less bow lift, planes at a lower speed and still manages 55mph at 4500rpm.
Prop was cheap as chips, too!

Toddely · **Posted:** Mon Jul 22, 2013 10:02 am

Well went out today with the new prop. 14.3 x 21 It ran at top Rpm right at 4100, My speed did increase to 47 mph. This was with 4 adults and half tank of fuel. Wondering if something is robbing me of power. any ideas? The engine doesnt miss or anything. This boat does have a dolphin tail bolted to the lower unit would this make a difference. It was on it when I received the boat?

ric · **Posted:** Mon Jul 22, 2013 10:34 am

Toddely wrote:

Well went out today with the new prop. 14.3 x 21 It ran at top Rpm right at 4100, My speed did increase to 47 mph. This was with 4 adults and half tank of fuel. Wondering if something is robbing me of power. any ideas? The engine doesnt miss or anything. This boat does have a dolphin tail bolted to the lower unit would this make a difference. It was on it when I received the boat?

4 adults robs a ton of power. From what I can recall my H180 didn't have any porpoising issues to speak of even loaded with 6 people. I would remove the whale tail and make sure you trim it out correctly on plane (not all the way down).

Toddely · **Posted:** Mon Jul 22, 2013 11:27 am

Ya thats what I was thinking , I really didnt see whey they put a whale tale on it. I do know it planes out fast. I am also still learning how to trim the boat out. how much trim up do you go at a time. are we talking like a split second with the trim switch at a time? Thanks for the input also. gotta love this place.

ric · **Posted:** Mon Jul 22, 2013 11:33 am

I can't remember how long I hold it up. Just raise it until you start to cavitate and go down a smidge. My current boat came with one and it serves no other purpose except a step to get onto the swim platform to save from putting the ladder down.

Toddely · **Posted:** Mon Jul 22, 2013 11:36 am

I am going to work on that this weekend. Thanks for all your input. I do know with the whale tale it didnt take much to make it start bouncing up and down.

rpengr · **Posted:** Mon Jul 22, 2013 12:08 pm

Toddely wrote:

I am going to work on that this weekend. Thanks for all your input. I do know with the whale tale it didnt take much to make it start bouncing up and down.

The whale tail is not likely to be your problem. At higher speeds, if you are trimmed up at all, the tail should be out of the water. It sounds like you have something else robbing you of power. You should be able to get the numbers that Deafwish gets.

Like Ric said, once you are well above planing speed, trim up until you hear prop aeration (or start bouncing, whichever comes first) then trim back down a little. For me, that is 3 to 5 seconds of trim up.

No, 4 people and 1/2 tank is not a lot. It will rob you of 2-4 mph, but not 10mph.

Toddely · **Posted:** Mon Jul 22, 2013 6:46 pm

That could possibly be some of the issue. (not properly trimming up)I can honestly say i haven't even got to that area of trim with my boat. Hmmm the student is heading back to the class room for my work. :lol:

I will go out with the admiral this weekend and practice and then I will get back to you and see how I do.. Thanks again

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odd prop size was on my horizon 180?

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