Alumacraft Edge 175 sport Yamaha F115XB installation questions

[neptun]

Hi guys!

I've just purchased brand new boat and it runs too slow.

My boat is Alumacraft Edge 175 sport with Yamaha 115 HP model F115XB latest.

I've attached official pdf file from Yamaha for older model of engine F115TXR. Current model is even more powerful.bulletin_4stroke_midthrustjetport_al_alm_competitor175sport_f115txr_2011-05-24_alm.pdf
Even with older engine model F115AX my boat should run at least 40.5 mph, but the maximum speed I get is about 35 mph based on 2 external brand new GPS's.

I did not complete break in procedure yet. Engine worked for about 7-8 hours.
So after 2 hours I'm allowed to run engine at any speed for short time.

Expected values are:
Maximum speed: at least 40.5 mph
Goes to plane mode at: 3500 rpms
Idle: 750+-50 rpms.

My real data are:
Maximum speed: 35 mph
Goes to plane mode at: 4800 rpms
Idle: 1050 rpms.

My prop is 13X19 inch black aluminum.

Dealership mechanics installed the motor.
The biggest problem now days is that there aren't many knowledgeable mechanics, who knows how to install and tune motor properly.
So I decided to ask my questions here.

I've attached few pictures.
Engine is being connected to the hull on the 2nd hole from the top. So we can install motor 1 hole down and 2 up.
Which hole slot engine should be installed?


Guidelines says that cavitation ( ventilation ) plate should be inline with keel.
But it's tricky to evaluate because keel line is not straight one.
Longest part of keel has small curve along. I refer to keel enforcement. It's about 10 feet long. Let's call it main keel line.
Last line of keel after enforcement continues upward. It's about a feet long. It makes some angle up compare to main keel line.


I tried to estimate if ventilation plate sits lower than keel line and how much. Engine was completely down.
To do that I "extended" main keel line with red broom stick. Red broom stick goes in parallel with main keel line on the left of it if you see from the bottom.
The stick is about 1 inch in diameter.


From that standpoint ventilation plate sits approximately 1 inch below keel line.
And it creates an angle between broom stick and ventilation plate lines. However tilting up and down does not change much max speed.

There are pictures of how engine sits in the water when on plane mode.
Ventilation plate is under water completely. The second plate is just above water line.


I really appreciate your advises.
Thanks in advance

[Ricky Spanish]

I have the same boat, but mine came rigged with a 150 Vmax SHO. I can consistently hit 48mph, but don't usually do much WOT. Someone on here can surely help you get it set up to your satisfaction. Other than the top end speed, how do you like the boat?

[neptun]

Originally Posted by Ricky Spanish

I have the same boat, but mine came rigged with a 150 Vmax SHO. I can consistently hit 48mph, but don't usually do much WOT. Someone on here can surely help you get it set up to your satisfaction. Other than the top end speed, how do you like the boat?

Overall I love this boat.
I did not have chance to try in in really rough waters, just in choppy ones. I would say it's steady ride due to double hull in the bottom.

Do you know what is the real difference in Vmax and F115XB engines, assuming the same HP?

[Ricky Spanish]

Sorry, I really am not knowledgeable about motors at all. 150 is bigger than 115, I am only sure of that much. Mine was pre-rigged at the dealer, so I didn't have to choose a motor.

We had ours out on Eagle Lake, ON in 3' waves last summer and it handled it very well.

[fishin4life2011]

I have a 2017 Competitor 175CS with the 115XB (Pre-Rigged Hole 2). Mine is a side console obviously and a slightly lighter weight than your Edge model. Mine Ran 37/38MPH and 5800RPM Planes at 3500RPM on the Stock 13x19 Aluminum prop with a half tank of gas 1 guy and 3 batteries trimmed up a bit.

I tried a 13.25x16 PowerTech RED3 Stainless Prop but it was too much prop. Ran 37/38MPH at 5500 RPM and planed at 3200RPM. Sort of Dogged the engine. Sounded more Strained and rattled at idle but handled much nicer and allowed for greater trim.

I also tried a 13x15 PowerTech SCD3 Stainless Prop. This one was smooth and hits 36/37MPH at 6200RPM. planed at 3800RPM. Has slightly better lift and rides a little higher than the stock prop.

Overall I was a little surprised with the lack of performance increases Yamaha brags about in their marketing materials but it is a very smooth and quiet engine. My buddy runs an older 2009 Navigator 175 Sport with the 115A using a 16p Mercury Vengence Prop. He sees 34-35MPH with 3 batteries, 2 fat guys and gear.

I think these 115B engines are tuned a little different than the A engine as the Redline is 6300RPM vs 6000RPM for the A. The Sweet spot (3000-4500) on the B engines is a little quieter and smoother. Perhaps these make less power in the mid range and more at the higher RPMs.

The difference between F115B and The VF115 SHO is the Tune. I think the 115 SHO is the same or similar to the F130 in World Markets. SHO is slightly more Power than what the sticker says.

I think you'd do fine with a PowerTech SCD3 in a 15p or 16p as well as a Yamaha Black SS in a 16p or 17p or Mercury Vengence / Quicksilver Silverado in a 16p or 17p. if you are seeking to experiment a little with prop. You will gain trim/lift/handling but not too much as far as speed. Maybe the new Alumacrafts tend to nose down a little more than the old ones? I don't know. Just my .02

[neptun]

Originally Posted by fishin4life2011

I have a 2017 Competitor 175CS with the 115XB (Pre-Rigged Hole 2). Mine is a side console obviously and a slightly lighter weight than your Edge model. Mine Ran 37/38MPH and 5800RPM Planes at 3500RPM on the Stock 13x19 Aluminum prop with a half tank of gas 1 guy and 3 batteries trimmed up a bit.

I tried a 13.25x16 PowerTech RED3 Stainless Prop but it was too much prop.

I also tried a 13x15 PowerTech SCD3 Stainless Prop.

I think you'd do fine with a PowerTech SCD3 in a 15p or 16p as well as a Yamaha Black SS in a 16p or 17p or Mercury Vengence / Quicksilver Silverado in a 16p or 17p. if you are seeking to experiment a little with prop. You will gain trim/lift/handling but not too much as far as speed. Maybe the new Alumacrafts tend to nose down a little more than the old ones? I don't know. Just my .02

Thanks SOO much fishin4life2011!
Really great answer. I was under impression that my boat is too slow. Currently I run 35 mph at 6200 rpm. It's in line with your lighter boat of 37/38 mph.

So what I need to understand now is how to improve performance for plane mode?
My problem is: Why I'm getting to plane mode at 4800 rpms?

I'm using 13x19 inches aluminum 3 blades prop from dealer. I don't even know if its from Yamaha or from Mercury. It's not written on it.
I would stay with aluminum prop but not ss one.

When I had 17 inches white prop from Yamaha my engine was running at 7000 rpm.
That's why I switched to 19 inches.

Soon I'm going to dealer to install vts switch.
Which aluminum prop should give me better to plane mode?

Is any setting on the engine itself to boost performance for mid range rpms?

My second problem is that engine runs at 1000 rpm idle.
Is any setup on the engine to low it down?

[yamaha1973]

Originally Posted by neptun

Thanks SOO much fishin4life2011!
Really great answer. I was under impression that my boat is too slow. Currently I run 35 mph at 6200 rpm. It's in line with your lighter boat of 37/38 mph.

So what I need to understand now is how to improve performance for plane mode?
My problem is: Why I'm getting to plane mode at 4800 rpms?

I'm using 13x19 inches aluminum 3 blades prop from dealer. I don't even know if its from Yamaha or from Mercury. It's not written on it.
I would stay with aluminum prop but not ss one.

When I had 17 inches white prop from Yamaha my engine was running at 7000 rpm.
That's why I switched to 19 inches.

Soon I'm going to dealer to install vts switch.
Which aluminum prop should give me better to plane mode?

Is any setting on the engine itself to boost performance for mid range rpms?

My second problem is that engine runs at 1000 rpm idle.
Is any setup on the engine to low it down?

Your tach is not reading right. There is no way that motor will hit 7000 RPM. The rev limiter would kick in sooner. Idle is 750-800 RPM

There is a dial on the back of the tach, they are set on 2 from the factory. You should be on 5. Or the tach is defective

[Northwoodswalleye]

I owned a voyager 175 with a yamaha 115 lb so the same motor lighter boat. I ran a 16 pitch stainless prop on it and it tached at 6200rpm (peak power is 6200) wide open and went 42gps. Fix the tach and go with a shorter stainless prop and you should be happier with the performance.

[neptun]

Thanks guys!

I will fix tachometer.
I will stick to aluminum prop. We have lots of rocks in Canadian shield lakes.

[lawson2343]

I agree with yamaha1973, your tach isn't reading right.

I bought a 175 Trophy last year with a Yamaha 115hp.

Took it out on the water the first time and was moving 20mph on my gps and the tach was over 6000 rpms. I knew that was wrong. Took it back to dealer and they indicated after fixing it that there were five different connections in the tach and the wrong one was used originally. When they got the right one, it now runs perfect. I'm around 5800-5900 WOT. With 3 guys, fishing gear, 24volt troller, 4 stroke kicker, I get right around 40mph GPS WOT.