motor weight guideline

[basslkjohn]

I want to hang a new 4 stroke on my 16 foot standard Lund fishing boat. But as I review even the 25 h.p. four strokes, the weight issue is a concern. I just saw a Suzuki 25 h.p. with three cylinders that I would like to buy...but the thing weighs 200 lbs. Is there a guide for how much weight I can hang on the transom for this boat? I thought some guys were running 50 h.p. two strokes or larger on similar boats..and those motors must run close to 200 lbs. I appreciate any advice.

[bassNspear]

what i would do is call a lund dealer, and they should be able to help you with this. That way, you dont go out and spend the money and you sink the boat!!

[Hula_Grub]

Hi- I'm a new poster here as well. I bought a new 14ft Lund classic last year. I got the 25 HP Mercury 4-stroke on my boat. The boat has a placard near the transom that says it was designed for a maximum motor weight of 265 lbs. The boat is rated for a maximum of 40HP and they sell this boat with the 40 HP merc on it.

Perhaps somewhere on your boat or your manual you have a similar limitation noted?

[basslkjohn]

Hey Hula: thanks for the reply. Is the 25 h.p. working out well on your boat? The Merc 25 looks like a big and heavy sucker.

[walleyewild]

Welcome Hula_grub

I have an older Lund with a 2 stroke 40 Merc. My motor weighs in at 177# and capacity only tells me 1165# total weight for people and gear.

25 on a 14' Lund that boat should get on plane quickly and just zip across the lake.

4 strokes are heavier then 2 strokes more moving parts but that motor should be way less then 265#

[marine_man]

Welcome to Fishing Minnesota Hula_Grub!

With respect to weight - I'm pretty sure the capacity plate has a maximum weight for people, motor & gear - if you're unsure weigh the boat, with your fully loaded gear, livewell etc and figure out what you have left for weight capacity.

marine_man

[Hula_Grub]

Thanks for the kind words and welcome all!

No, the motor isn't working out all that well. I should have gone with the 40 hp.

It will not plane with the livewell full- the live well is side mounted towards the rear. With just me in the boat I have to inch forward off the seat to get the boat on plane, then I can sit back down. With 2 in the boat, the other person has to move all the way forward until we're on plane- several very long seconds. According to Merc.'s site it weighs 157 lbs. dry. Put me in the back, gas, battery, trolling motor and it is very tail heavy.

It is a great motor in terms of gas mileage and starting right up and being very quiet. Not having to worry about having oil with me is also nice. But the 9.25" X 12.5 prop it came with didn't do me any favors. When I broke that prop (new guy!) I switched to a 10X11 composite prop and had the same performance problems. I have some 9" pitch blades on order that I hope to have in the Mississppi this week and will report back. The nice thing about the composite prop is I can switch out $15 blades whenever I want.

My original point was that I have a totally separate placard that relates to the max motor weight (265 lbs). Sure, I have the placards relating to total weight of gear, # of people, etc. so I was wondering if the original poster might have access to that info somewhere in his own literature.

[basslkjohn]

Hula: that was exactly my point as well. Given that my old Lund was built in the early 80's the rating tag only gives total weight capacity and maximun horsepower rating. Now we have a choice of 2 stroke or 4 stroke motors that have significantly different weights. So, for example, I suspect a 25 h.p four stroke weighs about the same as a 40 or 50 h.p. two stroke.

My dilemma is that I want a motor that will troll down and allow me to eliminate the electric trolling motor. I would like to have sufficient power to plane the boat, but I'm not worried about achieving 25 mph. I want to stay at or under 25 h.p. to use the boat in the BWCA. The weight of the four stroke may be too heavy to achieve these goals with a 25 h.p. Merc. and yet a two stroke 25 h.p. means I need the electric trolling motor.

Anyway, thanks for your analysis. I think it confirms my suspicions that the 25 h.p. four stroke would be an expensive disappointment.

[Hula_Grub]

The BWCA is the exact reason I got the 25. I totally understand.

I've only lived here in MN for 5 years. I've been to the boundary waters 6 times, once on a motor trip. I figured there was no reason that I, personally, would want a boat that I couldn't take up there. I've got a motor permit for Basswood on the opener this year, and I'm really excited.

Having stuck 3 people in rentals w/ 25 hp, I figured "no problem!" Problem is they were just your run of the mill Lunds w/ bench seats. Nice boats, but a lot less weight compared to mine. Plus the 2-stroke makes a world of difference getting over the hump.

It was on a trip to Kabetogama last year w/ all the camping gear that I really began to appreciate how much more motor my boat needed. If i would have been to Voyageur's NP before I bought this boat, I think I would have decided on the 40 hp and left the BWCA to canoeing and Voyageur's to motoring.

If the new, less pitched prop makes a big difference, I'll let you know if you want.

[basslkjohn]

I think we need an engineer to graph out the power to weight ratio of total loaded boat and motor to the horsepower of the motor. At some point on the resulting curve the marginal increase in horsepower is greater than the marginal increase in weight represented by the incremental increases in motor size. I didn't realize that your boat is considerably heavier that mine (I have the older Lund with traditional bench seats in a deep v 16 version). So maybe the 4 stroke 25 will work for me.

How does your 25 work for trolling? Can you leave the electric trolling motor at home?

[Hula_Grub]

Yeah- I think my boat is far heavier than one with bench seats. This being our first boat, we had an idea of what we wanted and sold it to ourselves based on limited past experiences.

Such a graph would be great.

For trolling, the motor is wonderful. I have to admit though, I'm more of a Bass guy and don't often troll. Like I mentioned earlier, it is a great motor, I think I just have it on the wrong boat vs. prop vs. weight.

I didn't think I'd run into this problem with it because I've been in BWCA outfitter jon boats with 25 HPs and sailed along at 18 MPH. 4 of us including driver, 2 canoes and a weeks worth of 2 portage gear. Granted, they are far better at loading a boat than I am.

If the new prop doesn't get me on plane with the livewell full, I'm going to have to try a hydrofoil. If that doesn't work, then I guess I just can't get on plane with a full livewell.

[basslkjohn]

My experience with the hydrofoil is very positive. With my current 35 h.p. and a just one person, the stern lifts and the bow noses down immediately upon acceleration. I wouldn't be without one on my motor...unless I had a power tilt unit. On my pontoon boat the power tilt seems to accomodate weight distribution very well. As people move around and weight shifts, I can adjust the prop angle to keep the floats level.

[Hula_Grub]

I got to try out the new 10x9 prop today. It's like I got a different boat. It jumps on plane, goes about 23 mph, and will plane out very quickly with the livewell full. I also get about 550 more rpms.

Maybe a 25 hp 4-stroke ain't so bad after all.