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Performance issues

Dahbull

Dahbull

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Recevied a new 25' QSR with cladded arch last week. Have the yamaha F300 motor and the dealer (or yamaha) placed a black painted stainless steel prop on the boat. Took it out for its first trip and the prop sounded like it was ventilating. Fastest speed we could get was 37 MPH at 6000-6100 RPM's. Dealer had already ordered a stainless steel prop for the boat but told me to stop by with the black prop and switch it to one he had. He actually provided two options, the second at my request. Don't know when the ordered prop will come and have not been able to test the new prop (lake the boat is on is now no wake). According to the yamaha web site we should be getting about 45 MPH.

Black prop was 15 1/2 x 15
Stainless 1 - 15 3/4 x 15 (with larger surface area)
Stainless 2 - 15 1/2 x 16

Second issue I noticed is the mounting height of the motor. While the dealer followed Benniningtons recommended mounting height I am not sure it is correct. The ventilation plate, when trimmed to be level with water at cruising, is above the water line and above the bottom of the center toon by about an inch. I feel this is causing the prop to slip and reduce performance. The problem is the motor is mounted as low as it can go on the transom. Looking closer at another brand of boat I was going to buy, their center toon is 27" in diameter. The shaft height of my motor is 25" and the shaft height of the motor for a 27" diameter toon as to be longer to accomodate. According to the yamaha web site, this other tritoon at 25' weighing 4,600 lbs can achieve 48.5MPH. I am thinking bennington is using the wrong shaft length (25") to apply to their boats. They should be using a 30" shaft and mounting the motor higher to get the ventilation plate at the correct height to acheive the performance that can be had from this motor and their tritoons.

Anyone have similar issues with a 25' QSR and an F300XCA yamaha motor?
 
The boat was designed for a 25” shaft motor. The other manufacturer you speak also adjusts there’s to work on a 25” shaft with a 27” tube. Some of there boats also allow for a 20” shaft as I tried to buy an HO motor off one and it obviously won’t work on mine. Without pics it’d hard to tell but I’d stick with finding the correct prop for that monster 300 and then work with the height if need be.
 
As I was told last year, focus on prop first. If you don’t get it dialed in with that, then move on to motor mount/height. Sure enough, dialing in the prop got me dialed in enough for my liking.

I think your prop pitch size is too small for the performance capability of the f300 on a tritoon. I also believe your rpm range is supposed to be 5-6000 on the f300 at WOT. Thus, you are slightly high on rpm as well, which both reinforced my thoughts on going up in pitch size, as well as a way to lower your rpm’s. If you are over-rpm’ing the motor, it will burn out.

I think you want to be as close as possible (but not over) your max rpm range on smooth water with a light load. Right now, you can go up in pitch size to work UP your MPH, and going up in pitch size should work DOWN your RPM. Each pitch size up should bring your rpm’s down about 200.

However, that’s second hand from following past threads. We have a 200hp Mercury, so that is the basis of my VERY small knowledge base on this topic. I am running on 16 pitch on ours to balance out speed at WOT with my rpm range.

I am hopeful of few of the other knowledgeable members on here with the Q-series boats and 300hp motors will chime in to help you out. Again, thinking you need to go up in pitch size to get more speed and lower your rpm.
 
I have two stainless props to test out. One a 15 pitch with 15 3/4 diameter. It also has a larger blade surface area than I have seen. The second is a 16” pitch with a 15 1/2 in diameter and standard surface area. I am curious which will yield a better result.

On my last boat, switching from a 15 pitch aluminum to a 16 pitch stainless netted about 5-6 MPH. If that holds true here I suspect I will see an increase to roughly 43 MPH. Still falling short of what I think this boat should do based on Yamaha’s charts.

I will know in a couple of days.
 
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I would say it is definitely your prop, you currently are using the same sized prop as I had on my 200, the 300 should definitely be different probably a 16 1/4 x 17. I think my 250 was a 15 3/4x 17. I think it says in my tag line below.
 
Nope, 15 1/2 x 17
 
Was looking at the boat in the marina today and noticed it leaning to the right (by two inches from water to deck). Found that odd so I talked to the dealer to see if the boat had any odd weighting issues. He said no. Pulled the boat onto the trailer and discovered that the right pontoon has water in it. We took delivery last thursday and the pontoon has a leak?????? I also checked the left pontoon and unless there is an echo from the right, it too as some water in it. My wife and I are beyond upset. Not to mention, this too would affect performance issues.

My question to this forum, to fix the issue the dealer now as to drill hole(s) in the pontoon to drain the water. Pressure test and find the leak(s). Repair the leaks and repair the hole(s) for draining the tube. This is a brand new boat and I truly feel this compromises the pontoons. 1) water/moisture is now inside the pontoons and can cause damage from the inside out. 2) holes drilled and the leak(s) being repaired may not hold up in the long term, 3) WHY DOES BENNINGTON NOT PRESSURE TEST THEIR PONTOONS BEFORE DELIVERY? If they do, then they missed one if not two pontoons not holding pressure.

What should I expect of the dealership and/or Bennington? We purchased Bennington for quality and this (along with a laundry list of issues we have found) need to be addressed. That's not the quality we paid for. We love the boat itself but are now left unhappy with the quality. What to do?
 
I'm going to bet you'll end up with a 17 or larger pitch prop when this is all said and done. Maybe even a 19.
 
Mine has never been a good representative of top speed because of my add ons, (stereo gear , 4 heavy batteries) but it was I think about 44.6 and 56-5700 (going from memory). There was an old thread where Carl recommended a Enertia 14.75 x 16 to a fellow with a 300 and he was at 46mph 6000rpm
 
Repairing of toons (welding) is the typical repair. They are not going to replace your toons due to a couple small leaks. What do you think they do if they find them at the factory? They repair the leak, not build new toons. They do test them at the factory, but sadly, some make it through which may leak after testing.
It’s still covered by structural warranty so just let them fix it and enjoy.

I think we are seeing more of this due to the high number of boats being built so the odds of “issues” increases.
 
Deleting the posts does not make the problem go away, only the posters. If BM can't handle the truth then that's pretty sad.
 
Water inside the tubes will not harm them any more than water on the outside. They are also FULL of welds, even when brand new! I know it's frustrating, but try not to sweat it much. It really isn't as big of a deal as it may seem. It can be fixed good as new.

One of my personal life lessons is to not let myself make big issues out of small issues. I save that for the really big issues. Life is much happier that way.
 
What posts?

Posts can be deleted from this site, but Google has them forever. I use Google regularly to find stuff on this site, and I've seen deleted posts there. Some were mine. I'm still here.
 
I feel your pain. When I picked ours up a couple of months ago it had a leak as well. It turned out to be a fairly easy fix and the dealer covered it. That being said, it is definitely disappointing especially from a reputable builder such as Bennington. I’d like to see valve stems on the chambers like the last brand that I had. That way you can check the pressure in them periodically to see if there’s any leaks. They also had about 5 psi in them to strengthen them up a bit and make them a bit more dent resistant. If they had the valve stems then the customer would be able to check them before it leaves the dealership.
 
Thanks for the replies.

Pressure testing and repairing a leak at the manufacturer is different than at the dealership after the leak is discovered.

At the manufacturer the toon has not been introduced to water and a pressure leak is simply a pressure leak where the weld can simply be reinforced. Repair complete.

Once the pontoon has been water filled the repair is more extensive.
1) Drill a hole (or two) to drain the water
2) insert a schreader valve into the drilled hole to pressurize the toon and find the other leak(s)
3) weld those leak(s)
4) remove the schreader valve and weld the drilled hole
5) Algae and any other product from the lake water entering the toon remains in the toon, permanently.

When we sell this boat someday, does something like this hinder resale value?
 
A repaired toon should not affect resale as more than you probably know have been repaired. There is a port already to do the air test it’s just up on top of the log. It has plug with a vent hole in it. As for any growths that shouldn’t be an issue as once repaired they’ll have no environment to grow.
 
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mattb said:
Deleting the posts does not make the problem go away, only the posters. If BM can't handle the truth then that's pretty sad.
Click to expand...

Typically a post will be deleted if it serves no purpose other than to add fuel to the fire, or it makes a statement such as “call Bennington” when the dealer has not even had a chance to rectify the situation. I personally will delete any post that states contact Bennington directly as this is what the dealer network is there for. Now, if the op states the dealer is dragging their feet, we then direct the thread to TB and allow them to address it.
 
You forgot political posts...
 
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