2015 Bayliner 175 Wont Plane with Four Adults in back-gctid813212

[CAMBO]

So, I recently bought my first boat that was only used for a year from the previous owner. During the test drive it was only myself, my wife, and the seller. The boat planed really well and handled well. After purchase, we took it out this past weekend for a family outing. The Driver weight ( 170), the front passenger weight (190), Rear Right weight (210), and Rear Left (170), with a full tank of gas. I could not plane with this load. Is that normal? It just seemed like it would not go anywhere and full throttle.. I moved the Rear Left passenger to the front of the boat and we were able to plane. I knew going into the purchase that the boats motor was not a racing motor, but I didn't think it was that weak in performance. It has the standard 3 prop with 135hp and only had 12 hours on the motor.

Also, I noticed I could not trim it over 50 percent without the prop coming out of the water and revving the RPMS. Is that normal? I could get it to 42 mph with three people in the boat. Any help would be appreciated.

The seller says it came with a transferable warranty, but not sure what all it includes. And ideas?

[CptCrunchie]

"CAMBO" post=813212 wrote:
So, I recently bought my first boat that was only used for a year from the previous owner. During the test drive it was only myself, my wife, and the seller. The boat planed really well and handled well. After purchase, we took it out this past weekend for a family outing. The Driver weight ( 170), the front passenger weight (190), Rear Right weight (210), and Rear Left (170), with a full tank of gas. I could not plane with this load. Is that normal? It just seemed like it would not go anywhere and full throttle.. I moved the Rear Left passenger to the front of the boat and we were able to plane. I knew going into the purchase that the boats motor was not a racing motor, but I didn't think it was that weak in performance. It has the standard 3 prop with 135hp and only had 12 hours on the motor.

Also, I noticed I could not trim it over 50 percent without the prop coming out of the water and revving the RPMS. Is that normal? I could get it to 42 mph with three people in the boat. Any help would be appreciated.

The seller says it came with a transferable warranty, but not sure what all it includes. And ideas?

First, welcome to BOC! Please take a moment to fill out your profile so we can learn a little about you, like where you live, what you will be using the boat for, etc. This really helps us when addressing your posts. (Click on your name, then hit 'edit'.)

IMO, the fact that you could get it on plane once you moved your 'load' means you may need some engine work. However, adding trim tabs could assist that too. As to the prop coming out of the water, you are trimming the wrong direction. You want to trim such that the bow stays down, which means the prop is as close to the transom as possible. Basically, that is what you did in moving the passenger; you flattened your profile, ....or the boats 'attitude'. If you have too much load in the back, you will be attempting to climb a steeper hill to get over the top where you will be on plane. Flattening your 'attitude' creates a smaller hill. In simple terms, the better your attitude, the less power you need to get on plane.

As to the transferable warrantee, that means you have one. But like any warrantee, some things are covered and some are not. Best you read it or have the seller/broker read it and explain it to you. OR, post it here.

IMHO, a 135hp on a 17' boat should have little problem getting on plane, no matter how it is loaded. It could just be the one on the helm. :whistle:

Congrats on your first boat, and welcome to BOC.

[itsabowtime2]

Smart tabs!!

Your boat will perform much better with them installed.

Do a forum search on the subject and you will find many posts.

[CAMBO]

First, welcome to BOC! Please take a moment to fill out your profile so we can learn a little about you, like where you live, what you will be using the boat for, etc. This really helps us when addressing your posts. (Click on your name, then hit 'edit'.) - I will do that, thanks!

IMO, the fact that you could get it on plane once you moved your 'load' means you may need some engine work. - Could you give me an example of what could be wrong? No leaks, weird sounds, and idles perfectly fine.

However, adding trim tabs could assist that too. I will look into smart tabs in the meantime. Easy to install for a DIYer or prefer professional install???

[Waterdowg]

Yes it sounds like you are trimming the wrong direction. You want the drive in full down position when starting off. If not you may see issues as you described. Once on plane you can then trim the drive to find your sweet spot. To do this only tap the the trim to move the outdrive up. Again just small taps. You will feel and hear the difference. If you go to high you will know ans just tap the switch down. Again small taps...... This will help you learn how your boat handles.

[CAMBO]

Yes it sounds like you are trimming the wrong direction. - Pulling out of the hole with all passengers in rear of boat was not possible with the weight of each passenger. I just cant see how that is normal. The front end would never go down with adding up trim or leaving it all the way down at full throttle. The boat would not get to plane until one 170 pound passenger went to the front of boat. Maybe this is normal for the small engine, I just I kinda hope I didn't buy a lemon considering I was told it only had 12 hours on the motor. If it was motor issues, what would I look for? I mean once the passenger moved seats, we were smooth sailing with no issue. I could never get the trim over 50 percent, which i guess I didn't need to.

[CptCrunchie]

"CAMBO" post=813227 wrote:
First, welcome to BOC! Please take a moment to fill out your profile so we can learn a little about you, like where you live, what you will be using the boat for, etc. This really helps us when addressing your posts. (Click on your name, then hit 'edit'.) - [color]orange wrote:
I will do that, thanks![/color]

IMO, the fact that you could get it on plane once you moved your 'load' means you may need some engine work. - [color]orange wrote:
Could you give me an example of what could be wrong? No leaks, weird sounds, and idles perfectly fine.[/color]

However, adding trim tabs could assist that too.[color]orange wrote:
I will look into smart tabs in the meantime. Easy to install for a DIYer or prefer professional install???[/color]

I'm no mechanic - as my signature space eludes to - but understand it could be a number of things. You also could have had a mechanical survey done on the engine prior to purchase so you'd know if there was an issue. But since that is in the past, suggest you find a good Merc service shop and let them tell you if there is any issues with it. If we knew where you lived, we could likely recommend a good one in your area. 'hint-hint'

I'll let someone else address the smart tabs.

[CptCrunchie]

"CAMBO" post=813232 wrote:
Yes it sounds like you are trimming the wrong direction. -[color]red wrote:
Pulling out of the hole with all passengers in rear of boat was not possible with the weight of each passenger. I just cant see how that is normal. The front end would never go down with adding up trim or leaving it all the way down at full throttle. The boat would not get to plane until one 170 pound passenger went to the front of boat. Maybe this is normal for the small engine, I just I kinda hope I didn't buy a lemon considering I was told it only had 12 hours on the motor. If it was motor issues, what would I look for? I mean once the passenger moved seats, we were smooth sailing with no issue. I could never get the trim over 50 percent, which i guess I didn't need to.[/color]

Yikes! Wow! Okay, .....where to start.

Any boat - no matter what size - needs to have a balanced load for fuel efficiency, ride, ease of getting on plane, etc. Your engine could likely be good; you just need to learn how to use it.

First and by far, foremost, what do you mean 50%? You mean you are bringing your outdrive half the way up? Yikes!!!!!!!

As someone else stated, to get on plane, you need your outdrive all the way down. Only once it is on plane, do you even touch the trim, and even then it is only in the tiniest of movements. If you are raising it more than 5-7 degrees, you are likely your boats worst enemy. I call it 'bumping the trim', indicating it is just like bumping into someone until they move. Same goes for a boat.

Another possible option is to change your prop when you carry heavier loads. Reducing your prop pitch gives more oomph to your hole shot making it jump quicker onto plane. Just remember to change it back when you carry smaller loads, especially if you like to go fast; you could easily over-rev your engine, and that is an expense you don't want to deal with.

[builderdude]

You had nearly 900lbs in you boat in the form of fuel and passengers alone, my guess is you had some other things onboard as well? Let's round it to 1000lbs of weight and all of it was likely in the ass end. That's likely why it struggled to plane out. Once the passenger moved up front it came up on plane. Personally I'd say that's probably normal for that situation.

On your drive trim: this should be all the way down untill your on plane then as suggested previously, bump it up till its singing. Be sure your drive limit is functioning as it should, your drive should only trim up to its set limit, anything beond that can cause damage$.

If loaded like that most of the time you may want to look into a different prop.

[freechip]

With my 175 I had no such issues when loaded with even more. I had purchased it with a 19p prop and changed to a 21p prop because I would most often be 3-4 people and less. With 4 people onboard and even 5-6 I didn't have any issues pulling a tube.

As for trimming, trim all the way down and once you are on plane and moving you can then trim up and the 175 only requires 1/4 trimmed. I didn't need trim tabs on my 175, proper load placement is always something the captain needs to take care of. I remember I was a kid my dad would always move us around in the fishing boat.

[Don77]

Not being able to plane with 4 adults (2 in the back of the boat) is normal for a 17 Ft boat with only 135 Hp!

I have a friend tha has that same boat and with 2 adults in the back it strugles to get on plane!

Redistribute your load including people and enjoy the boat! Just be aware that it has minamal HP and is not a race boat, but a fun 1st boat!

Enjoy and safe boating!

Don

[Waterdowg]

"CAMBO" post=813232 wrote:
Yes it sounds like you are trimming the wrong direction. -[color]red wrote:
Pulling out of the hole with all passengers in rear of boat was not possible with the weight of each passenger. I just cant see how that is normal. The front end would never go down with adding up trim or leaving it all the way down at full throttle. The boat would not get to plane until one 170 pound passenger went to the front of boat. Maybe this is normal for the small engine, I just I kinda hope I didn't buy a lemon considering I was told it only had 12 hours on the motor. If it was motor issues, what would I look for? I mean once the passenger moved seats, we were smooth sailing with no issue. I could never get the trim over 50 percent, which i guess I didn't need to.[/color]

I'm not sure how much boating experience you so I hope I don't offend you. That boat should plane fine if you trim the engine correctly. You need to start with the outdrived trimmed all way down. Once you start moving at a good speed, you will feel this on the boat as the nose will start to lower. This is were you need to bump the trim up to find the sweet spot. But trimming the engine up 50% or more is not good. You will over rev the engine and the prop will wash out.

[Solandri]

"builderdude" post=813249 wrote:
You had nearly 900lbs in you boat in the form of fuel and passengers alone, my guess is you had some other things onboard as well? Let's round it to 1000lbs of weight and all of it was likely in the ass end. That's likely why it struggled to plane out. Once the passenger moved up front it came up on plane. Personally I'd say that's probably normal for that situation.

To try to understand this intuitively, if your boat + payload weighs 4000 lb, the water needs to exert 4000 lbs of upward pressure on the hull for the boat to float. The "upward" part means you can ignore the 3D profile of the hull. All you need to do is imagine a 2D projection of your hull's outline in the water (a top-down view basically). Multiply that surface area by the water pressure to see if your boat will float.

Water at sea level exerts 14.7 PSI. As the hull sinks into the water, the water pressure increases (it's about 16 PSI just 3 feet down). Eventually the hull sinks deep enough that the increased water pressure counteracts the weight of the boat + payload, and your boat floats.

When you're trying to get your boat on plane, you're trying to do the exact same thing. Except instead of the water pressure increasing because the hull sinks further into the water, the water pressure is increasing because it's hitting the hull with some velocity.

But surface area is still a factor. Because (weight) = (pressure) * (surface area).

When you have everyone sit in back, the boat tilts and the back sinks further into the water. Since it sinks deeper, the water pressure increases. The weight remains the same however. So to keep the above equation in balance, the hull surface area in contact with the water has to decrease. If you try to get onto plane in this configuration (with this amount of tilt), there is less hull surface area for the water to hit. Consequently the moving water has to hit the hull with more velocity to lift the boat out of the water. Apparently your engine does not provide enough power to move the boat quickly enough (make the water hit the hull with sufficient velocity) to lift the boat onto plane in this configuration.

When you sent someone forward, the boat leveled out a little. The back rose up, decreasing the water pressure. Consequently the surface area in contact with the water had to increase. With greater hull surface area in contact with the water, the water did not have to hit the hull with as much velocity to lift the boat onto plane. Trim tabs perform the same function - adjusting the tilt (angle of attack) of the boat hull against the water without you having to shift weight around.

This is somewhat counter-intuitive - the more you tilt the bow up, the *harder* it is for the boat to lift out of the water and get onto plane. It makes sense if you think of it as climbing a ramp. The steeper the ramp (the more the bow is tilted up), the harder it is to climb. If your engine is powerful enough, you can certainly just power up the steep ramp quickly. But in most cases you're better off using a longer ramp with a gradual slope, so the engine doesn't have to work as hard to get you up the ramp.

Once the boat is on plane, the drag is greatly reduced (you've mostly eliminated what's called wave-making or displacement drag). So the engine can move the boat faster, meaning the water hits the hull with more velocity (more pressure). So the person you sent forward can move back again, and the boat can remain on plane even at the original tilt where it couldn't get onto plane.

"CAMBO" post=813212 wrote:
I knew going into the purchase that the boats motor was not a racing motor, but I didn't think it was that weak in performance. It has the standard 3 prop with 135hp and only had 12 hours on the motor.

Boat engines and props are a lot harder to optimize than cars. With a car, the many gears of the transmission allow you to have multiple optimal operating points. Boat engines don't have geared transmissions, so it's like driving a car with only a single gear. Usually that gear is optimized for cruising speed (going fast). So when you're trying to get onto plane, you're operating in the non-optimal region of the engine and prop's performance envelope. The boat's performance in that region, especially with an unbalanced load, does not necessarily mean the engine is weak. You need to get up on plane and see how fast it can go with 4 people aboard to make that determination.

(Small recreational boats don't have transmissions because they add weight and complexity. And unlike a car whose tires don't slip against the road, a boat prop can easily slip against the water. So you can rev the engine to get the boat moving forward from a stop, despite not having a "low" gear.)

[Jack_Skell]

I had the same problem in my 20' 1971 Fiberform trihull with 120 hp inboard outboard. 3 adults, bogged, no plane. Sent a passenger and the cooler to the open bow and got on plane.

I knew the drive trim hydraulics were shot (so the drive was kept directly on the stern with the prop thrust), but I didn't know my motor wasn't developing full power until a little later. I figure I was down maybe to 70ish percent.

Still fun.

[Nickdixon]

One of my original posts and the reason I joined this forum involved this issue...and I have a lot more power than you with a bit bigger boat. I was really disappointed, thought I had spun a prop, thought I might had over-revved the engine, and so on. My prior experience had been on boats without adjustable trim back in the '70's.

Turned out that:

1. I was not even intending to begin the hole shot with the prop closest to the boat (trim fully down on my boats gauges) and

Worse,

2. The trim gauge on my boat indicates "level" when it is just lower than trailering position. I though level meant medium trim. Not so, it was in its upmost position for operation.

I discovered all this on BOC and have not had an issue since then at all.

I learned to ski and drive a boat on a 17 footer with a Merc 115. Four of us, all very lean teenagers, with one driving and the three of us in the back...would not plane. Move one guy to the front, all was good. The point is, you are in a medium that can be displaced, a bit similar to an airplane. Any pilot does a weight and balance check before taking off...failure to plane in that case is exactly that and that failure to get speed is a stall. With planes and with boats, the smaller they are, the more weight and balance of cargo affects performance.

So...the boat is not the problem. It's just that you need to learn it's limitations. But don't expect a different brand, or a new model, or even a modest increase in size or power will eliminate the effect you have experienced.