Back to the main site

2014 Q25 low max RPM and speed

Q

Q25

Member
Messages
7
Reaction score
17
Hi all,

I'm new to Bennington's and pontoons but have had a few boats before including most recently a 21' center console. I just took delivery a few weeks ago of a new to me 2014 Q25 with a Yamaha F250XCA and a Yamaha SWS2 17"x15.5 prop, 400 hours. This has the EPS Tritoon package with lifting strakes. I just filled the gas tank with new ethanol free gas at the local marina. The engine sounds like it is running well but the performance and speed at the top end feels like it's just missing. At WOT I'm getting 24.3 mph by gps in good conditions and lightly loaded, with the motor at 4300 RPM. This seems way too slow, right? I calculated that this is 40%+ prop slip. It feels like it gets out of the hole well and operates well up to about to about 3000 RPM where it's getting about 21mph. Any ideas about things I should check out first or go about diagnosing? I'm wondering if I'm getting cavitation on the prop, or the VST system needs cleaned? Any other suggestions to look at?

Thanks!
 
Last edited:
Hmmm, it sounds to me that you’re in need of a new prop. I’ve got a similar setup (2016 2574 GCW with a 250 Verado) spinning a 15.6x13p prop which will generate 40+ MPH @ 6400 Rpm WOT. Sounds like you’re lugging your engine.

You might want to give Ken @ propgods.com a call for prop suggestions. Good luck and report back what happens.
 
Plus 1 for propgods.
Your RPM's are low ,should be 5800-6000 and hit about 40 MPH .
I have a 23 ft QCW with a 250 Verado, I can hit 45. 2 adults ,full tank and clean toons
 
I just checked the suggested prop chart that Bennington provides to dealers. With a F250XCA, on a 25ft the suggested prop is 15 3/4 X 15 Saltwater SDS.
 
Great, thanks for the suggestions! I'm going to try a new prop and report back. Good to know that this should be a 40+ mph boat, that's what I expected so I was surprised when it really didn't perform anywhere near that at WOT
 
Proped correctly, about 40 ? A 2014 Q is a Very Heavy boat . 2014 ,still had 16 inch on center cross members . ( added weight)
 
Do you have a Wave Shield ? I previously had a 2014 RCW ( same platform) it was an option.
 
The waves hitting the cross members will slow you down a bit also
 
Jack M said:
I just checked the suggested prop chart that Bennington provides to dealers. With a F250XCA, on a 25ft the suggested prop is 15 3/4 X 15 Saltwater SDS.
Click to expand...

i have a 2023 L24 with the 250 SHO, and this same prop... SPS+ hull... not apples to apples, but you are likely way overpropped....
 
At first glance, not a prop issue.

I can turn a 17p with my F250 and get 5800 RPM. Hell with a 19p prop I could turn 5500 RPM.

To have such low RPM it's either an engine or fueling issue, and perhaps even a hull/toon issue. I would start with the visual inspection stuff first - making sure you have clean toons. I lost 17mph just recently due to crud covered bottoms. Then are your toons sitting unusually low in the water? Making sloshing sounds when on the trailer? Water in the toons will definitely put load on that engine and prop.

Check all of your maintenance items. Could be a fueling/filter issue but maybe electrical as well (plugs?). Honestly it could be many things so I would always start with the easy items then get progressively more involved. Also the F250 is a very popular outboard so consider posting on other boards such as the Hull Truth can also help in your diagnosis.

Good luck!
 
Potomacbassin’ said:
At first glance, not a prop issue.

I can turn a 17p with my F250 and get 5800 RPM. Hell with a 19p prop I could turn 5500 RPM.

To have such low RPM it's either an engine or fueling issue, and perhaps even a hull/toon issue. I would start with the visual inspection stuff first - making sure you have clean toons. I lost 17mph just recently due to crud covered bottoms. Then are your toons sitting unusually low in the water? Making sloshing sounds when on the trailer? Water in the toons will definitely put load on that engine and prop.

Check all of your maintenance items. Could be a fueling/filter issue but maybe electrical as well (plugs?). Honestly it could be many things so I would always start with the easy items then get progressively more involved. Also the F250 is a very popular outboard so consider posting on other boards such as the Hull Truth can also help in your diagnosis.

Good luck!
Click to expand...
Interesting…. I can only get 5800 with my setup. I’ve always wondered if the motor was mounted at the right height…. Could be at play for me, and the OP….
 
jcr159 said:
Interesting…. I can only get 5800 with my setup. I’ve always wondered if the motor was mounted at the right height…. Could be at play for me, and the OP….
Click to expand...
I have a SXP23 so our setups are probably very similar. I'm in the #3 hole and it provided very good increase in fuel efficiency and a little more top speed (2mph). Tradeoff is in turns it can lose a little more grip, but thankfully not really blow out.

I'm also spinning a Q3/Enertia prop which is 14.5x17. Some 17p props are a little more diameter which could ventilate more in turns if you raise the engine.
 
Potomacbassin’ said:
I have a SXP23 so our setups are probably very similar. I'm in the #3 hole and it provided very good increase in fuel efficiency and a little more top speed (2mph). Tradeoff is in turns it can lose a little more grip, but thankfully not really blow out.

I'm also spinning a Q3/Enertia prop which is 14.5x17. Some 17p props are a little more diameter which could ventilate more in turns if you raise the engine.
Click to expand...
Ok, good info, I’m in the lowest hole and still lose a little bite in hard turns especially when pulling tubers. I’m also pretty sure the SWSII props aren’t as efficient as the enertia. Feels like folks are able to run roughly a “size” larger in pitch or diameter with them for similar RPM compared to the SWSII’s. Top end seems similar either way though…. Not enough difference for me to drop that kind of money messing around until mine needs replaced….
 
Yeah my only saving grace is I wanted to have a spare on hand, I traded the SWS19 for a SWS16 and have that sitting in a box ready to go. At least every 2 years I send the Enertia off to a prop shop to get tuned and the spare keeps me on the water, not to mention having it on hand should I ever lose the Enertia. Almost happened the other day - performed my annual prop/prop shaft check and found the prop nut had back off about 3 threads, and my guess is probably was only a few trips from throwing it. Lucky. Also found some nasty braided fishing line around the shaft seal, thankfully no apparent damage.
 
Potomacbassin’ said:
Yeah my only saving grace is I wanted to have a spare on hand, I traded the SWS19 for a SWS16 and have that sitting in a box ready to go. At least every 2 years I send the Enertia off to a prop shop to get tuned and the spare keeps me on the water, not to mention having it on hand should I ever lose the Enertia. Almost happened the other day - performed my annual prop/prop shaft check and found the prop nut had back off about 3 threads, and my guess is probably was only a few trips from throwing it. Lucky. Also found some nasty braided fishing line around the shaft seal, thankfully no apparent damage.
Click to expand...
No prop lock?!?
 
Potomacbassin’ said:
Yeah my only saving grace is I wanted to have a spare on hand, I traded the SWS19 for a SWS16 and have that sitting in a box ready to go. At least every 2 years I send the Enertia off to a prop shop to get tuned and the spare keeps me on the water, not to mention having it on hand should I ever lose the Enertia. Almost happened the other day - performed my annual prop/prop shaft check and found the prop nut had back off about 3 threads, and my guess is probably was only a few trips from throwing it. Lucky. Also found some nasty braided fishing line around the shaft seal, thankfully no apparent damage.
Click to expand...
Hmmm, I’ve never sent my prop in for tuning. Is that really a thing if you’ve never hit anything? Sometimes at very low speeds, it feels like I have a slight wobble but I always felt that was the result of mass production.
 
BigKahuna said:
No prop lock?!?
Click to expand...
I have the prop lock, and that's the problem! They use a sprung washer (Belleville washer is the official name) that locks the nut instead of a cotter pin. But if the washer fails for any reason the nut can start backing out. I'm still not sure how it happened and need to figure out a solution before I end up donating $800 to the river Gods.
 
Michiman said:
Hmmm, I’ve never sent my prop in for tuning. Is that really a thing if you’ve never hit anything? Sometimes at very low speeds, it feels like I have a slight wobble but I always felt that was the result of mass production.
Click to expand...

The better guys will spend time re-balancing your prop in addition to honing all the surfaces, making any repairs etc. But a low speed wobble is probably more just a function of the natural vibration of the engine, unless it's really severe. Have you ever struck bottom where maybe the prop shaft might be slightly bent? I guess the only way to know is to send the prop off and see if it changes anything, but it's not cheap!
 
Potomacbassin’ said:
The better guys will spend time re-balancing your prop in addition to honing all the surfaces, making any repairs etc. But a low speed wobble is probably more just a function of the natural vibration of the engine, unless it's really severe. Have you ever struck bottom where maybe the prop shaft might be slightly bent? I guess the only way to know is to send the prop off and see if it changes anything, but it's not cheap!
Click to expand...
Thanks for the feedback. No, my skeg looks like new and I’m not aware of a strike. It’s not much of a wobble and not always noticeable, so I just figured the tolerances on props are probable not quite like aircraft parts.
 
You must log in or register to reply here.
Back
Top