15hp not able to plane 14ft aluminum

Hi all!

Just purchased a '05 Lund 14.5' WC DLX and '05 Merc 15 hp 4 cycle. I took it out for the first time yesterday and was surprised that I can not get the boat to plane even on still water and WOT.

Boat is 14.5', 69" beam and 390lbs. With trolling motor, batteries, and everything else on the boat, I'm probably looking at 800-1000lbs.

Is this motor too small for what I'm asking it to do? Or, perhaps, something else I can check?

Thanks!

~gcap

Re: 15hp not able to plane 14ft aluminum

Well, that model is rated for 25hp tiller, so you're a bit under the max. Quite a bit. Still, it should plane the boat with just one person.

Can you describe what the boat does when you go WOT? How is the weight distributed in the boat? How much does the operator weigh (I know...that's personal)? How is the outboard trim set?

It's going to be a delicate balance to get your Lund on plane that far under the rated horsepower, but it should be possible.

Re: 15hp not able to plane 14ft aluminum

I had a similar rig for my previous rig. It was an 06 Sylvan Alaskan deluxe 13 and I had an 05 4 stroke Merc 9.9 HP on it.

Boat was rated for a 25 too. Most of these utility boats Lund, Smokercraft and Sylvan are all basically almost the exact same models (Smokercraft and Sylvan are the same company now).

You have the same issue I had. First in 05 some Merc's models were heavier. In 07 they lightened them up considerably. Last year I bought an 06 40hp and returned it two weeks later cause I found out the 07's were a lot lighter.

The other issue I had was that if I upgraded to a 25 hp, I couldn't have more than two aboard (3 people and I could only do 5 mph. If you put a 3rd person along with the heavy merc 4 stroke 25 a trolling battery and gear etc you will be over the boats max rating and the transom will be an inch above the water line (I rented a 25 to see if it could handle it).

I could get mine to plane with the 9.9. I could get it up to 20mph with just me too.

Here's what I did with mine. Buy 4 foot red and black battery extension cables at Walmart. Buy two bolts and washers and bolt those cables together to lengthen your trolling motor cables (if it's a transom mounted one like mine was). Then you can also buy their $5 battery box and now you can put your battery in the center of the boat.

Also, pick up a tiller handle extension (about $20) these extend about 3 feet and now you can steer the boat as you sit on the middle seat. That tiller extension also works with the trolling motor.

Makes it nice for cruising around a lake too cause you can sit next to the other person.

Short of that, you could always get an extension hose and put the plastic 6 gal tank in the middle of your rig too.

But the first two will work for sure and make your rig more enjoyable. You can't throw all the weight on the transom and expect these 14 footers to perform well.

The 05 9.9 an
d 15 hp were the same block and close to the same weight. I know your motor is heavy. 2 strokes perform a lot better than 4 strokes on these small boats, but I personally wouldn't own a 2 stroke.

Let me know if you try these suggestions and how they worked out. Also there might be problem with the Merc. That 06 one I returned had a throttle cable problem. Even my 9.9 Merc had TWO recalls for the throttle cable and linkage problems. Call a dealer and give them the serial #. Ask if there were any recalls. If there were they will fix it for free.

Oh, I see this is your first post, welcome aboard

Re: 15hp not able to plane 14ft aluminum

Thanks guys. All good responses.

I do have a lot of weight on the transom end (merc, trolling motor, battery for running lights/pump, another big battery for trolling motor, plus myself (200lbs) The gas tank is on a long hose and in the middle of the boat already.

I think I might try to remove the trolling motor and battery and see how that works. That should take about 75 lbs off the transom.

I was also thinking of experimenting with another prop aside from the stock one. Any ideas there?

I've rented 14' boats w/15hp 2 cycles and just felt like they I was able to get them to plane a lot easier than I'm finding with this setup.

Re: 15hp not able to plane 14ft aluminum

Move the load in your boat instead of removing it. It sounds like you need more weight toward the bow to get better weight distribution. Next time you go out, play with the load in different positions, even moving the battery 12" back or forward can make a difference.

I have 2 group 31 batteries, 3 gallon gas tank, and anchors (150#+) under the middle seat of my 14' jon boat. There's a 7.5 HP and trolling motor hanging off the transom and it hauls with 1 person (240#), add a kid and it still hauls. With a second adult I can tell it's down on speed, but still planes.