Bennington QX25 Build w/ Mercury 350 or 400

rownbey8

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Planning to order a new QX25 within the next week. I have talked myself out of going with the Yamaha 350 with all if the issues (fly wheel) I have read about online. This leave me with the Mercury Verado 350 & Mercury Verado 400 options.

Does anyone have any experience with the Mercury 350 or 400 on a Bennington?

Is the 400hp motor over kill for the QX25?

Is there any advantage of one over the other? I know I will see greater top end speed with the 400 but will I see more mid range torque?

Any feedback would be greatly appreciated
 
Welcome Rownbey8! I'm not sure you're going to find too may folks with either the Merc 350 or 400 but there are a couple. That said, hardly anyone complains about too much HP so I'd go with the 400 and eliminate any second guessing. Be sure to post some pictures once you have her delivered!
 
Is the 400hp motor over kill for the QX25?

Is there any advantage of one over the other?

Is there such a thing as HP over kill for a boat? :D

If you can afford it, absolutely go with the 400 HP on that boat. The Q’s are an amazing boat, but they are a big and heavy boat. Should finances allow it, and you are looking at the same motor manufacturer (Mercury), then go with the biggest you can get. If you don’t, you’ll always wonder “what if”.

I have a Mercury Verado Pro and absolutely LOVE it. However, mine is not in the HP ballpark of what you are looking at.
 
I think you would find that the real world difference in performance between the Mercury 350 and 400 would be negligible. From the research I did, top speed difference is not expected to be more than 3 mph. Not sure about any mid-range difference. As mentioned above, it’s a heavy boat and will never be considered very fast, regardless of engine choice. That being said, I would go with the 400 mainly due to the fact that the difference in cost relative to the price of the boat isn’t that significant. That was initially my plan. I’m in Mercury country. It’s interesting the differences regarding engine manufacturer preference by region. I have friends across the country that swear by one manufacturer over the others. Ultimately, I view it as a Ford vs. Chevy type of argument. I ended up with the Evinrude 300 due to the fact I found the exact boat I wanted in terms of spec that was pre rigged for Evinrude. Fortunately, I’m really pleased with the performance. I saw 46 mph on GPS with two hours on the engine last week. (Engine mounted in lowest position.). I was expecting 42-43mph. There are obviously a number of variables affecting performance, but you will be happy with either of your engine choices. It really is a great boat. Good luck!
 
I own a 2019 Q25, although not the X...

Running the 350 on it...

Just wrapped up a full year this month

Ran it at close to sea level in Lake Havasu, AZ...

Spent time on Lake Shasta @ 1000ft above sea level...

And finally, my home lakes here in central Oregon - ranging from 2800ft to 4700ft...

Top speed in Havasu was just shy of 52...

Top speed at 4700ft @ Cultus Lake, OR - 48...

IMHO - The 350 does absolutely everything one needs or wants...
 
Planning to order a new QX25 within the next week. I have talked myself out of going with the Yamaha 350 with all if the issues (fly wheel) I have read about online. This leave me with the Mercury Verado 350 & Mercury Verado 400 options.

Does anyone have any experience with the Mercury 350 or 400 on a Bennington?

Is the 400hp motor over kill for the QX25?

Is there any advantage of one over the other? I know I will see greater top end speed with the 400 but will I see more mid range torque?

Any feedback would be greatly appreciated

May I ask,
What "issues" are you speaking of? When I first read your post, I tried to find "issues" with the F-350 Yamaha 350 V-8. Well, at present, all I could find was some sort of "flywheel" issues on or around, the 2004 - 2005 era engines. Now, for me at least, that's a 10 year span between that and my 2014 F-350 version. Now, I must say, that at present, we only have 30 hours on our 2014 boat and motor. We bought it about a month ago, with only 24 hours on it. That engine runs like a top or, sewing machine, whichever describes the smoother, quieter operation. No vibrations, no odd sounds, no issues at all, that I'm aware of. So, this is why I ask about the "issues" you've read about. Thanks.
Scott
 
Planning to order a new QX25 within the next week. I have talked myself out of going with the Yamaha 350 with all if the issues (fly wheel) I have read about online. This leave me with the Mercury Verado 350 & Mercury Verado 400 options.

Does anyone have any experience with the Mercury 350 or 400 on a Bennington?

Is the 400hp motor over kill for the QX25?

Is there any advantage of one over the other? I know I will see greater top end speed with the 400 but will I see more mid range torque?

Any feedback would be greatly appreciated
Ru
 
Running a 350 Verado on my 2019 Q25. I consistently get highs 40’s with cladded arch and Bimini open. Very happy with performance. That being said, the QX is a heavier boat so a 400 might be the ticket. Hope this helps. Don’t think you can go wrong with either one
 
May I ask,
What "issues" are you speaking of? When I first read your post, I tried to find "issues" with the F-350 Yamaha 350 V-8. Well, at present, all I could find was some sort of "flywheel" issues on or around, the 2004 - 2005 era engines. Now, for me at least, that's a 10 year span between that and my 2014 F-350 version. Now, I must say, that at present, we only have 30 hours on our 2014 boat and motor. We bought it about a month ago, with only 24 hours on it. That engine runs like a top or, sewing machine, whichever describes the smoother, quieter operation. No vibrations, no odd sounds, no issues at all, that I'm aware of. So, this is why I ask about the "issues" you've read about. Thanks.
Scott


Scott,

Mainly the flywheel issue, somewhere in the 3,000-4,000rpm range after 80 hours of operating you will need the flywheel changed. This is the main reason Yamaha changed to a 5 year standard warranty on the F350. Also a Bennington dealer that is a Yamaha only dealer stated Yamaha is discontinuing the F350. Make sense because the new Yamaha brochure doesnt even show the F350 in it. It goes from the 425 straight to the 300. This is my main reason for going with the Mercury 400. Plus the Mercury 400 is about $11k cheaper than the Yamaha 425.

Thanks
Rodney
 
Hey Rodney,
I appreciate you getting back to me on this. Apparently my previous research limited me to the earlier years of the F350. But, with a bit more digging, it appears that the "flywheel" issue can creep up into possibly even my year, 2014. In all the research I did, I only found one document that *basically* explained the problem/issue. And, for many of the F-350 owners, any replacement of the flywheel and, accompanying ECU, was on Yamaha's bill. But, some weren't so lucky, if you want to call something like that "luck". So far, in the limited research I've done, there appears to be no series of a production run of this particular engine, that's affected.

Our boat, a 2014 Benny 25RCL is new to us. It came with the F350. We just purchased this 5-year old boat, approximately 1.5 months ago, with a whopping 24 hours on it. I think we've got 31 hours on it now, maybe a bit more. The motor is great. But, I'm learning about it now. I guess all I can do now is keep an eye on things, watch the hour meter and monitor the *offending RPM's*. Thanks for the tip.
Scott
 
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Honestly, even if there were not any issues with the flywheel, the money differential alone would justify the Mercury 400 if it is $11k less than the F350 Yamaha. Am I understanding that correctly? For such a price difference, why wouldn’t someone go that route? :cool:
 
Honestly, even if there were not any issues with the flywheel, the money differential alone would justify the Mercury 400 if it is $11k less than the F350 Yamaha. Am I understanding that correctly? For such a price difference, why wouldn’t someone go that route? :cool:

I kind-a wondered about that too. I'm not planning on building a new Benny with that kind of choice anyway. But, logically, it seems to me that, if that were the case, a 400HP motor that's $11,000 cheaper than a 350HP motor, hmmm. But, I'd have to see the total picture, including specs of all of them to really get behind all of it. So far, in the very, very limited amount of use we've had with our "new to us" Benny with the Yamaha F350, absolutely zero complaints. But, time will tell.
Scott
 
Honestly, even if there were not any issues with the flywheel, the money differential alone would justify the Mercury 400 if it is $11k less than the F350 Yamaha. Am I understanding that correctly? For such a price difference, why wouldn’t someone go that route? :cool:


Jeff

The Mercury 400 was ~$11k cheaper than the Yamaha 425. Hope this clears it up

Thanks
Rodney
 
Honestly, even if there were not any issues with the flywheel, the money differential alone would justify the Mercury 400 if it is $11k less than the F350 Yamaha. Am I understanding that correctly? For such a price difference, why wouldn’t someone go that route? :cool:
The mercury 400 is not $11,000 more than the Mercury 350. Both Yamaha and Mercury 350 are virtually the same price on the boat builder at $30,500. Keep in mind you pay no where near that number. The Yamaha 425 is $11k more than the Mercury 400. Just wanted to clear up any confusion. The price on Mercury 400 in my opinion is very good.
 
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I own a 2019 Q25, although not the X...

Running the 350 on it...

Just wrapped up a full year this month

Ran it at close to sea level in Lake Havasu, AZ...

Spent time on Lake Shasta @ 1000ft above sea level...

And finally, my home lakes here in central Oregon - ranging from 2800ft to 4700ft...

Top speed in Havasu was just shy of 52...

Top speed at 4700ft @ Cultus Lake, OR - 48...

IMHO - The 350 does absolutely everything one needs or wants...

Based on this alone, it sounds like the 350 would be enough! I thought 250 hp was enough for my R. In fact if you search you might find a post where I mumbled something about even being okay with less at one time. Keep in mind if you run this at full throttle, you'll burn a gallon every two minutes!! That and you won't be very popular with anyone other than kids while you're doing it. The driver is usually the only one truly enjoying WOT, at least in my experience anyway! With a 400 or 425 it will burn 25% to 30% MORE but will NOT give you 25% more speed! Less than 1/2 that I'm sure, possibly only a few more mph.
 
I certainly appreciate you getting back here and clearing things up. Sometimes forums are like campfire talks/games. You say one thing at the beginning of circle of people, and by the time it gets around the circle and back to you, it's totally different. Man, these engines are ALL high priced!
Scott
 
But they are great motors. For the most part 99% of people on these forums love their motors! It is amazing how reliable these motors are compared to 30 to 40 years ago.
 
Based on this alone, it sounds like the 350 would be enough! I thought 250 hp was enough for my R. In fact if you search you might find a post where I mumbled something about even being okay with less at one time. Keep in mind if you run this at full throttle, you'll burn a gallon every two minutes!! That and you won't be very popular with anyone other than kids while you're doing it. The driver is usually the only one truly enjoying WOT, at least in my experience anyway! With a 400 or 425 it will burn 25% to 30% MORE but will NOT give you 25% more speed! Less than 1/2 that I'm sure, possibly only a few more mph.

Nautical,
That was a very well written post. Now, not all people operate boats, no matter almost what kind of boat, in the same manor. I'm not made out of money, never have been, never will be. So, while we did spend more on this boat than we've done for several of our cars/trucks/motorcycles etc. over the last several years, I still take notice of our fuel use, just to be efficient and yet still have fun. And that means we run at about 30-35 mph for probably around 85-95% of the time. It's INSANELY RARE that I open her up to full throttle. I might, MIGHT open up to WOT once every other trip out. And that's for about 1-2 minutes max.

To me, the advantage of having the larger motor is the use of POWER if and when you need it. 99.9999% of boating is Leasure. But, there's always a chance you need to "get out of Dodge" in a hurry for some odd reason. Plus, when the boat gets loaded up with humanoids, the extra power is there to help with more leisurely cruising, with out working the snot out of a lesser power engine. And, you're definitely right about the primary ones that get a "rush" out of WOT are KIDS, for the most part. KIDS, are not paying for FUEL, I AM!!! Again, nicely written and great logic.
Scott



But they are great motors. For the most part 99% of people on these forums love their motors! It is amazing how reliable these motors are compared to 30 to 40 years ago.

Alicedream,
We've had 6 boats in our boating career over about 36+ years. And this is our first outboard motor. The wife really wanted an in-out motor on our next boat. She thought because the engine would be lower and tucked in, under the rear floor, there would be more room for sun deck and lounging on the tail. And, that it would be easier to climb back on the boat from the water, without that engine in the way. Well, yeah, there's some merit to that point. But, the cost of that is, it's incredibly tough to work on an in-out in a pontoon. And that makes it EXPENSIVE. Not saying that a shop working on an outboard is all that much cheaper either. And besides, there's plenty of room to climb back on that boat, using the provided extendable ladder. Anyway, yes, this motor, the F350 Yamaha we have, is one seriously strong motor. And, IT'S MASSIVE on the back of that boat. Everyone that pops over to see our new boat is flabergasted when they come around to the back and see that MONSTER on there.
Scott
 
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