Engine Mounting Hole and Propellor Recommendations

[Fairway]

What engine mounting hole (height) is best suited for a 20LLG with a Yamaha 115F?
What prop/pitch would be recommended?
(We typically have two to four adult passengers and will occasionally pull tube. Freshwater lake.)
I'm sure the dealer plans to install at what height and prop they like. Would just like to know what other folks are doing.
Oddly I spoke with Bennington regional rep and he told me the dealer "should" have a chart for this info and I asked him to tell me the recommended or send me copy of the chart and he said that information was proprietary!?? I said.... "its just mounting holes and prop pitch etc." how is that proprietary? Oh well any insight appreciated.
Thanks F.

 

[Vikingstaff]

What engine mounting hole (height) is best suited for a 20LLG with a Yamaha 115F?
What prop/pitch would be recommended?
(We typically have two to four adult passengers and will occasionally pull tube. Freshwater lake.)
I'm sure the dealer plans to install at what height and prop they like. Would just like to know what other folks are doing.
Oddly I spoke with Bennington regional rep and he told me the dealer "should" have a chart for this info and I asked him to tell me the recommended or send me copy of the chart and he said that information was proprietary!?? I said.... "its just mounting holes and prop pitch etc." how is that proprietary? Oh well any insight appreciated.
Thanks F.

It will help if you also share what HULL you have: normal dual toon, Elliptical dual pontoon, Partial tritoon ETP, or full tritoon SPS or ESP. This will factor in greatly with recommendations.

Also, do a search through the thread below for a boat similar to your model, layout, size and hull. You might find good ideas there as people have listed their set ups with prop and what not over time once they get them dialed in.

List Your Specs Here

 

[Fairway]

It will help if you also share what HULL you have.

Full tritoon SPS and the LLG layout has two bow loungers. I'll take a look at the thread you mention.
Thanks! F

Edit to add My dealers responses.
Me: What propellor and what pitch do you install on a tritoon boat this size?
Dealer: Solas 13
Me: Which engine mounting hole (height) do you typically install to?
Dealer: This will be the top hole

Hmmmm.....

 

[Potomacbassin’]

Generally the higher up you go the more speed and fuel efficiency. Tradeoff is turning and potential ventilation of the prop. You'll have to determine what your objectives are and make adjustments from there, but sounds like you would benefit from a "balanced" approach.

I'm two holes up from the bottom with no straightline issues, so I imagine I could go all the way up and be fine. But my 23' squats astern due to the weight of the big motor so that may allow for more height - and maybe not the case with everyone.

Prop for a 115 generally is an aluminum based on posts I've seen here. SS will provide some marginal benefits but probably not enough to justify the extra expense. Yamaha or Merc prop is best, but many run Solas with good results. Check the respective manufacturer sites using their prop selector to get some ideas, but also comb the forum here as Viking noted as well.

You nailed it - dealer will throw whatever prop is available to them to get your boat splashed and payment coming their way. With supply chain disruptions during Covid I've seen some real garbage fitted onto new customer boats so you're wise to demand what you want upfront. You can always tweak down the road, but once they have your check in hand you will get at the back of the line to get any propping issues resolved. A good dealer will do their best to accommodate you so hopefully that is your case.

Good luck!

 

[Fairway]

Thanks Potomac - Balanced sounds good to me for a start unfortunately when i asked the dealer their prop intention and response was "Solas 13" which is a really lazy and vague excuse for a prop description let alone a P/N grrrrrr. I have no idea if their interpretation of "Solas 13" is SS or Alum or diameter for that matter. I had read SS wasnt going to make that much difference on a pontoon boat. I tried differnt prop/pitches on my previous boat all aluminum. It was a bear during tight turns and could hear some cavitation but it planed out nice cruising. I guess it will be trial and error on this new boat which is no big deal on the prop but I damn sure cant move that engine up and down in my garage.
I'm really disappointed in the lackadaisical responsiveness of the boat industry as a whole. Its feast or famine and they are feasting right now and accountable for nothing. I dont think they give a damn if i buy the boat or not. The dealer told me a couple of months ago they would give me my downpayment back if i wanted as they knew they could sell it to someone else bc of the shortage. Wow.

 

[mtudb24]

as said before, many engine / toon manufactures run either Yamaha or Mercury (enertia)props. I'm surprised it doesn't come with a Yammi prop? 13" diameter seems small for a 115hp. Is the sale based on a water test and performance needs to meet your expectation?
I ended up moving my motor up 1 hole due to the fact that the cavitation plate was well over and inch lower then the bottom of my motor pad.
With a full 3rd tube, you have a lot of "wet surface area" , the 13 number they gave you was that Diameter or pitch (maybe i missed that above?)
If its diameter, then I would have to think there isn't enough surface area to push that boat. Enertia props start at 13.5" diameter and goto 16" and pitch can go from 11 to 22 or something like that. Typically when pitch goes down, Diameter goes up. So if its a 13P, the diameter must be in the 14.5 to 15.5 size.
I would try to ask the dealer for the full spec of the prop. Diameter and pitch

 

[Potomacbassin’]

I hear you Fairway, I had felt the same way at times with my dealer. So I put in the work to develop a good relationship with the owner and it's been good since. Still not perfect but as you noted, times are good right now for the industry as a whole and they don't need to bend over backwards to make a sale. Reading other posts I'm just happy to have a boat with a working motor on it!

Prop-wise you're going to want to test at least two if not more - the benefit of those Al ones are you can test relatively cheaply. IIRC from other posters you won't want to exceed 13p as you'll start falling out of specified WOT RPM range beyond that. Max speed will be in that low-30 range.

Gonitro has a good recent thread on this with all of his prop test data, so that can provide a good baseline. If that Solas comes close then your dealer has done his part - you can tinker with others as time and $ allows.

115HP Yamaha SHO Prop Pitch?

Hello all, New to the forum and new to owning a 2021 Bennington 21ft SLX (performance package 3rd toon) with what I believe is a 13.5- 17P prop. It appears to be the standard Yamaha aluminum white anodized 17P prop they use for these engines. (not new to driving all my drunk friends boats back...

club.benningtonmarine.com

I know some guys will use a floor jack and straps from the ceiling (or tree?) to raise the motor. Dealer will charge you an arm and a leg and take 12 weeks so maybe call the boys over for some pizza and beer?? Or if you can wait do it when your 20 or 100-hour service is up and have dealer raise motor at same time?

 

[Michiman]

Thanks Potomac - Balanced sounds good to me for a start unfortunately when i asked the dealer their prop intention and response was "Solas 13" which is a really lazy and vague excuse for a prop description let alone a P/N grrrrrr. I have no idea if their interpretation of "Solas 13" is SS or Alum or diameter for that matter. I had read SS wasnt going to make that much difference on a pontoon boat. I tried differnt prop/pitches on my previous boat all aluminum. It was a bear during tight turns and could hear some cavitation but it planed out nice cruising. I guess it will be trial and error on this new boat which is no big deal on the prop but I damn sure cant move that engine up and down in my garage.
I'm really disappointed in the lackadaisical responsiveness of the boat industry as a whole. Its feast or famine and they are feasting right now and accountable for nothing. I dont think they give a damn if i buy the boat or not. The dealer told me a couple of months ago they would give me my downpayment back if i wanted as they knew they could sell it to someone else bc of the shortage. Wow.

If I had to guess, your dealer is talking about a 13P aluminum prop. Generally, the rule-of-thumb is SS at 150HP and above. As for engine height, Vikingstaff for one has done a post which walks you through the basics. Use the search box above to find it. As Potomac said, there are definite trade-offs to keep in mind. Good luck!

 

[Fairway]

Today I drove to the dealer (2hrs) to look at our boat sitting on the trailer w/out a motor. Waiting on the 115F. Boat (20LLG SPS) looked good. Yacht Club P2035TG looked good but I noticed there was no bunk under the center tube. Dealer said, "oh thats an add on kit...its on order". (They've had the trailer 3 months...hmmm).
Anyway the Parts Dept. said they install SS props on all engines over 90HP and mine would get a Solas 13-3/4 x 13P RH. I asked if that is a good all around prop verses a pitch more for tubing or a pitch for top speed cruising and.... Oh.... Boy.... he got spun up about how there is no such thing as a prop for this or a prop for that but only one correct prop that is determined by correct pitch that achieves target 6000 RPM at WOT blah blah blah or something along those lines. He also said they will mount engine in top hole on my boat per the chart. I could tell hes had this "discussion" once or twice a week with customers for 20 years. I had my '06 Premier 225 Legend for 14 yrs did all the service myself including props and never ever took it back to the dealer once and I hope to god that is the case with this new boat. Cheers!

 

[Vikingstaff]

Today I drove to the dealer (2hrs) to look at our boat sitting on the trailer w/out a motor. Waiting on the 115F. Boat (20LLG SPS) looked good. Yacht Club P2035TG looked good but I noticed there was no bunk under the center tube. Dealer said, "oh thats an add on kit...its on order". (They've had the trailer 3 months...hmmm).
Anyway the Parts Dept. said they install SS props on all engines over 90HP and mine would get a Solas 13-3/4 x 13P RH. I asked if that is a good all around prop verses a pitch more for tubing or a pitch for top speed cruising and.... Oh.... Boy.... he got spun up about how there is no such thing as a prop for this or a prop for that but only one correct prop that is determined by correct pitch that achieves target 6000 RPM at WOT blah blah blah or something along those lines. He also said they will mount engine in top hole on my boat per the chart. I could tell hes had this "discussion" once or twice a week with customers for 20 years. I had my '06 Premier 225 Legend for 14 yrs did all the service myself including props and never ever took it back to the dealer once and I hope to god that is the case with this new boat. Cheers!

Doesn’t sound like he has learned much in working with customers for these past 20 or so years. Sorry you are stuck working with this person on getting your boat set. They certainly don’t know as much as they should regarding prop impacts on pontoon performance or motor mounting impact on pontoon performance.

Eventually you’ll be past all this and enjoying your boat. Hang in there.

 

[Potomacbassin’]

Doesn’t sound like he has learned much in working with customers for these past 20 or so years. Sorry you are stuck working with this person on getting your boat set. They certainly don’t know as much as they should regarding prop impacts on pontoon performance or motor mounting impact on pontoon performance.

Eventually you’ll be past all this and enjoying your boat. Hang in there.

Viking, you are ever the diplomat and a true gentleman! That's one of the things I think we all like about you!

Me on the other hand... Fairway this guy sounds like an idiot. With the statements he's made I wouldn't want him within 100 feet of my motor. Thankfully he's parts and not service. If you end up with the stated prop it probably won't be a bad starting point so at least take comfort there.

Motor height - there is no chart that can determine what's right for your particular set up and objectives. You know what you're doing so trust your instincts and experience over some parts jockey.

 

[Vikingstaff]

I try. A hold over from being a teacher I suppose. What I say and type is not always reflective of less diplomatic thoughts bouncing around in my head. Ha, ha!!!

 

[Fairway]

Apparently my engine came in Tuesday. I was notified tonight via email everything is ready. Also said in the email they took it out for a water test. That irritates TF out of me as I asked them last week if we could take it out before signing and the answer was "No, we don't do water tests on boats". (They are 5 mins from a large lake).
So I replied back to my sales rep's email tonight and asked why tell me "No" water test yet you take it out and test and not let me know!???
Response, "I didn’t know they were going to either but the service manger decided to. We have never brought in a triple toon 20’ and wanted to make sure it ran great with the recommended prop, 13 pitch and it did not. So they switch it to a 15 pitch so it would get the correct rpm.
Assuming the target RPM for a Yamaha 115F is 5900RPM at WOT and the 13P prop was over revving (they didn't tell me). And assuming they then took it back to the shop slapped a 15P on there and said good to go.
Also - Since they told "Me" no test drive yet they took it out and obviously reached WOT to verify the correct RPM my concern to that is
The manual states, "
1. For the first hour of operation: Run the engine at varying speeds up to 2000 r/min or approximately half throttle.
2. For the second hour of operation: Increase engine speed as much as necessary to put the boat on plane (but, avoid full-throttle operation), then back off throttle while keeping the boat at a planing speed.
NOTICE: Failure to follow the break-in procedure could result in reduced engine life or even severe engine damage.
I do not think they went out on a 2 hour test drive and eased into it and followed the manual. I'm sure they cleared the ramp, got to open water and nailed it tinkered with throttle noticing over revving, tried a few times more then took it back to the ramp. They probably spun the rod bearings.

 

[gotnitro]

Apparently my engine came in Tuesday. I was notified tonight via email everything is ready. Also said in the email they took it out for a water test. That irritates TF out of me as I asked them last week if we could take it out before signing and the answer was "No, we don't do water tests on boats". (They are 5 mins from a large lake).
So I replied back to my sales rep's email tonight and asked why tell me "No" water test yet you take it out and test and not let me know!???
Response, "I didn’t know they were going to either but the service manger decided to. We have never brought in a triple toon 20’ and wanted to make sure it ran great with the recommended prop, 13 pitch and it did not. So they switch it to a 15 pitch so it would get the correct rpm.
Assuming the target RPM for a Yamaha 115F is 5900RPM at WOT and the 13P prop was over revving (they didn't tell me). And assuming they then took it back to the shop slapped a 15P on there and said good to go.
Also - Since they told "Me" no test drive yet they took it out and obviously reached WOT to verify the correct RPM my concern to that is
The manual states, "
1. For the first hour of operation: Run the engine at varying speeds up to 2000 r/min or approximately half throttle.
2. For the second hour of operation: Increase engine speed as much as necessary to put the boat on plane (but, avoid full-throttle operation), then back off throttle while keeping the boat at a planing speed.
NOTICE: Failure to follow the break-in procedure could result in reduced engine life or even severe engine damage.
I do not think they went out on a 2 hour test drive and eased into it and followed the manual. I'm sure they cleared the ramp, got to open water and nailed it tinkered with throttle noticing over revving, tried a few times more then took it back to the ramp. They probably spun the rod bearings.

Trust me, I get the reasoning your ticked off, I cant stand my dealer either. I know a few people that took their brand new outboards and ran the sh!t out of them right outa the gate, not doing any 20 hour service ETC. In fact they didn't do any service till the end of the season, engines still run great. Not recommended but, is what it is..

On a side note, I have a 21ft with a 115vmax, a 13.5-12P was too small, ended up with a 13.5 -14P Hits 6K at 35.7MPH with me alone on it. I find it hard to believe that a 13P was over revving.. I wasn't over revving with my 12P, just wasn't at its top speed. You might have to do some prop chasing for your boating style. It's aggravating and will cost you $150-$180 a shot per Yamaha aluminum prop.

 

[Potomacbassin’]

There is an RPM limiter so I'm not sure how the dealer determined it was over revving. Maybe it HIT the limiter and determined that the could go up in pitch, but again it doesn't sound like you're dealing with a full deck of cards with these guys.

Like Nitro noted you'll have to do your own testing. Also dealer owes you a check ride so make sure all the other stuff is working before you hand over payment - once the money is transferred your importance to them goes WAY down and any warranty or rigging issues will take forever to get resolved.

 

[Fairway]

Nitro - I know there are folks who would run the shit out of a motor out the gate. Im a 30 year machinist and I would not. I had a 115 Merc for 15 years and had zero issues. If I dont get that out of this Yamaha I will always suspect the original "water test".
I spoke with the "Tech" who did the water test on the phone. He was a real AH
He told me the 13P was reaching 6400RPM (the "over rev", he did not mention an RPM limiter). He said they tried 3 props a 13P, ??P and the 15P. 15P was 6K RPM at WOT He wouldn't tell me the 2nd prop size. He said "it didnt matter, I dont have time for this, next question" I do mean a genuine d*ck. Got really argumentative when I quoted the 2K RPM max first hour of engine operation per the manual. Said "I'm a 50 years exp. engine tech and the manual break in didnt apply to a him setting up a boat but YOU need to follow the engine break in per the manual." OH - he did say they idled it on a water hose at the shop for 30 mins before the test so i guess that is my peace of mind.
Poto - He never mentioned RPM limiter. Keep in mind I requested a water test twice and was told "NO" yet they performed a test without telling me. The tech told me he "didnt want to hear a thousand questions" and "didnt want have someone looking over his shoulder". Could I have walked? Yes. They told me 2 months ago they'd give my down payment back bc they could easily sell the boat. My wife would have shot me.
Bottom line - they need a fng team seminar on customer service or i suspect will go under in 3 to 5 when the 'ive got you over a barrel boat demand goes away'.
I have the boat in my drive and installing a GPS/Fishfinder and i hope to get it in the water today!
Edit: Strike "peace of mind" the hour meter shows 0Hrs .2Mins 0.2Hrs

 

[Potomacbassin’]

What a jackwagon.

For reference my boat was fitted from the dealer with a WAY undersized prop - basically one that was intended for an F150. My motor hit the 6200 rev limiter with ease, with a lot of throttle left to go. The ECM definitely is protecting the engine by overiding throttle input.

What your dealer may be saying is that anything over the target operating range of 5-6K is an "over rev", but I think most people would disagree with that. An over rev in my mind is when the engine is under load running WOT and the prop suddenly unloads (hitting a wave that pops the stern out of the water) and it spins beyond what the ECM can control. That is a true over rev which can destroy lots of things including the LU, and I believe the ECM records that data for warranty denial purposes down the road.

I would be done with these guys forever, they're clearly done with you now that the sale is complete and it's only going to piss you off more. Maybe consider sending some documentation to Bennington and Yamaha just in case something mechanical happens in the future. Unlikely but you never know.

 

[Vikingstaff]

What a jackwagon.

I would be done with these guys forever, they're clearly done with you now that the sale is complete and it's only going to piss you off more. Maybe consider sending some documentation to Bennington and Yamaha just in case something mechanical happens in the future. Unlikely but you never know.

My thoughts and advice too. I hope…hope…hope you have another dealership service options than this place. I can also appreciate that often people don’t. IF you do, switch. You’ll feel better not giving these rude and non-customer service focused people more of your hard earned money.

I partically like the idea above of sharing this experience with Bennington. It is a highly sought premium brand. When a dealership treats their Bennington customers this way, it reflects on Bennington. Fair or not, it does. I think Bennington corporate is vested in making sure its dealership network works in a positive manner with their boat owners. Reaching out to Bennington will likely result in Bennington reaching out to this dealership.

Either way, glad you got your boat and can move on. I would have so wanted to tell them to take that boat and shove it up their A_ _ after speaking to that person. Man, oh man would I ever have wanted to do that. I can only imagine being in your shoes.

 

[gotnitro]

Nitro - I know there are folks who would run the shit out of a motor out the gate. Im a 30 year machinist and I would not. I had a 115 Merc for 15 years and had zero issues. If I dont get that out of this Yamaha I will always suspect the original "water test".
I spoke with the "Tech" who did the water test on the phone. He was a real AH
He told me the 13P was reaching 6400RPM (the "over rev", he did not mention an RPM limiter). He said they tried 3 props a 13P, ??P and the 15P. 15P was 6K RPM at WOT He wouldn't tell me the 2nd prop size. He said "it didnt matter, I dont have time for this, next question" I do mean a genuine d*ck. Got really argumentative when I quoted the 2K RPM max first hour of engine operation per the manual. Said "I'm a 50 years exp. engine tech and the manual break in didnt apply to a him setting up a boat but YOU need to follow the engine break in per the manual." OH - he did say they idled it on a water hose at the shop for 30 mins before the test so i guess that is my peace of mind.
Poto - He never mentioned RPM limiter. Keep in mind I requested a water test twice and was told "NO" yet they performed a test without telling me. The tech told me he "didnt want to hear a thousand questions" and "didnt want have someone looking over his shoulder". Could I have walked? Yes. They told me 2 months ago they'd give my down payment back bc they could easily sell the boat. My wife would have shot me.
Bottom line - they need a fng team seminar on customer service or i suspect will go under in 3 to 5 when the 'ive got you over a barrel boat demand goes away'.
I have the boat in my drive and installing a GPS/Fishfinder and i hope to get it in the water today!
Edit: Strike "peace of mind" the hour meter shows 0Hrs .2Mins 0.2Hrs

So with that newly added pic of the tach, I'm trying to figure out if you're saying they were running the engine without it being hooked up to the hour meter OR did they just lie about testing the props on water?

 

[Fairway]

Thanks for all the feedback. I wonder if this "tech" could have reset the ECM other wise I dont see how he could have done all that he said he did in in .2Hrs (12 minutes?). Im going to take a breath and decide on reporting all this to Bennington. TBH I had several phone calls with the southeast sales rep during the manufacturing/delivery phase and though he was knowledgeable and did call me back when I left him voicemails etc. he was at wits end with the other thousand customers constantly calling him and asking for status (he told me this).

Regardless got her on the water yesterday! Chugged around at 2K for 1st hour then got her up on "plane" in the 2nd hour per the manual. Has a smooth "happy place" around 4K but didnt go over that. Manual says for the remaining 8hrs of breakin can take her to WOT but not for more than 5 minutes at a time until 10 hrs of run time. She sits a tad stern heavy but levels out around 4K and anxious to get her to WOT today! Will let you know where she tops out speedwise later!!

Edit: Nitro - Maybe he did unplug it or maybe lying or both.
Also - What engine do you guys have and what RPM at WOT?