Loaded weight on trailer - 242 E-Series boats?

[fraserjr]

Has anyone taken and E-Series boat to a weigh station to see what a fully loaded boat and trailer weighs? I know I can run some rough estimates, but curious to see if anyone has some real world numbers (full tank of gas, full shower tank, gear, etc.)

Thanks!

 

[Matt Phillips]

I haven't rolled my boat across a scale, but I figure rolling down the road, I'm likely close to 6400-6500 pounds. Here's how I do the math:
Yamaha claims dry weight on the trailer for 2017 is:
242 Limited E = 5010
242 Limited-S E = 5210
242 x E = 5382
Yamaha has no reason to under/over inflate these numbers so they should be pretty accurate.

Gasoline weighs about 6.3 pounds per gallon so a full tank of fuel is 315 pounds.
Water weighs 8.3 pounds per gallon so a full tank about be about 83 pounds.
The wild card here is all of the other stuff in the boat. I estimate 700-1000 pounds for all of those tools, anchor, lines, cooler, pull toys, life jackets, etc.

Thus, my math is as follows:
242x = 5382
Fuel = 315
Water = 0 (no shower & manual says to never tow with ballast tanks full)
Treasures = 700
Total = 6397

in comparison to my 2009 Limited S (which weighed about 3300lbs) the 242x weighs about 4000. All things being equal, I can tell that extra 700lbs is harder to pull (as the old diesel doesn't get as good of fuel economy). But I figure when pulling the boat, it'll take whatever fuel it's going to take to pull it.

 

[Mainah]

You could figure total weight rather accurately using stuff you may have around the house. You can use the pipe, board, and bathroom scale method to get a precise tounge weight. While still on the board very accurately mark the contact patch of the tires and use a very accurate digital tire pressure gauge to record the tire pressure in PSI. Precisely measure the length and width of the tire contact patch in inches in decimal format then multiply those figures and the psi from that tire. Repeat for all 4 tires then add the tire figures and the tounge weight figure and you have total weight.

Better yet do this with your kids (guide them in doing the measuring and math while explaning the principles) to prove that geometry and physics is useful in daily life. Garuntee they will never forget doing this even if they forget how.

 

[swatski]

You could figure total weight rather accurately using stuff you may have around the house. You can use the pipe, board, and bathroom scale method to get a precise tounge weight. While still on the board very accurately mark the contact patch of the tires and use a very accurate digital tire pressure gauge to record the tire pressure in PSI. Precisely measure the length and width of the tire contact patch in inches in decimal format then multiply those figures and the psi from that tire. Repeat for all 4 tires then add the tire figures and the tounge weight figure and you have total weight.

Better yet do this with your kids (guide them in doing the measuring and math while explaning the principles) to prove that geometry and physics is useful in daily life. Garuntee they will never forget doing this even if they forget how.

I would like to see the data at different pressures to see if it's a linear effect with a zero y-intercept or not. And also by comparing the unloaded pressure vs loaded pressure.

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[swatski]

Yamaha has no reason to under/over inflate these numbers so they should be pretty accurate.

My only hesitation would be - if they try to "fit" the gross weight data into some trailer regs. (I know, I know, imagine that!... they would be trying to use cheaper trailers). But that was an issue with 190s - single vs dual axle limits, and brake requirements in some states.

But I would think you are probably very close for the actual.

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[Jgorm]

You could figure total weight rather accurately using stuff you may have around the house. You can use the pipe, board, and bathroom scale method to get a precise tounge weight. While still on the board very accurately mark the contact patch of the tires and use a very accurate digital tire pressure gauge to record the tire pressure in PSI. Precisely measure the length and width of the tire contact patch in inches in decimal format then multiply those figures and the psi from that tire. Repeat for all 4 tires then add the tire figures and the tounge weight figure and you have total weight.

Better yet do this with your kids (guide them in doing the measuring and math while explaning the principles) to prove that geometry and physics is useful in daily life. Garuntee they will never forget doing this even if they forget how.

But that doesn't account for side wall strength. Do that with load c then load e and it will be wildly different. The bathroom scale tongue weight is also very rough. I gave up and bought a hanging scale that I hang off a high lift jack.

 

[Mainah]

I would like to see the data at different pressures to see if it's a linear effect with a zero y-intercept or not. And also by comparing the unloaded pressure vs loaded pressure.

--

Lets say you fill a tire to 35 psi while not on the vehicle and then put it on the vehicle under load; the pressure will still be 35 psi. The change is that the tire deforms increasing the contact patch (surface area). In order for this method to work you must have enough weight to make the tire start to deform. The priciple is easy enough in that you have a known surace area and known pressure exerting force on that surface area. Of course there will be a neglible impact of the resistance provided by the tire tread and sidewall which could be measured volumetrically in a tank but then the whole thing becomes harder to do to make up for a negligible difference. The hardest part of this is marking the contact patch accurately in my opinion.

Anyone reading this please be aware I am not an engineer and there may be something I am not accounting for but based upon MY understanding of physics I don’t see whay this won’t yeild rather accurate results. If you are an engineer please do chime in even if it is to ridiclue my idea.

 

[Mainah]

But that doesn't account for side wall strength. Do that with load c then load e and it will be wildly different. The bathroom scale tongue weight is also very rough. I gave up and bought a hanging scale that I hang off a high lift jack.

The bathroom scale method is dependent upon accurate measurement/placement but accuracy is easy enough to achieve. I concur that direct calibrated measurement will always yeild more accurate results but without paying for vehicle scale pads or going to an industrial scale this will serve to be pretty accurate without spending a dime. Alternatively one could also use 3 bottle jackss with pressure gauges and known bores to do the same type of thing.

 

[Jgorm]

$70 bucks and you know for sure. I used this while placing my jeep on a car trailer. It ended up I needed it way more forward than expected. Like 4' farther! That's an application where you need to drive on the trailer and the bathroom scale is not ideal. It also makes it easy to weigh any load you might lift.
Horizon 500 KG / 1100 LBS Digital Crane Scale Heavy Duty Industrial Hanging Scale https://www.amazon.com/dp/B00ZWAKSVO/ref=cm_sw_r_cp_apa_VLsFAbWEFGRZ3

 

[fraserjr]

$70 bucks and you know for sure. I used this while placing my jeep on a car trailer. It ended up I needed it way more forward than expected. Like 4' farther! That's an application where you need to drive on the trailer and the bathroom scale is not ideal. It also makes it easy to weigh any load you might lift.
Horizon 500 KG / 1100 LBS Digital Crane Scale Heavy Duty Industrial Hanging Scale https://www.amazon.com/dp/B00ZWAKSVO/ref=cm_sw_r_cp_apa_VLsFAbWEFGRZ3

This is only going to give you tongue weight though right?

 

[Jgorm]

Yes. Aside from a giant crane and load cell, the only at to get an accurate weight is a truck scale. Or maybe 4 automotive corner weight scales and something like I got for the tongue, but those are $1000+.

 

[swatski]

This is only going to give you tongue weight though right?

Even then - you will need to be perfectly leveled front to back - or just forget about ANY degree of accuracy.
If you want the actual weight, weight station or it’s a waste of time. IMO.

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[Mainah]

This discussion has inspired me to create a “scale” capable of 24k lbs. I disassembled my 12 ton bottle jack to measure the bore diameter with a micrometer (1.8900 inches). I am going to order two or three pressure gauges of varying ranges so that a low range one can max out and then read the next instead to achieve accuary across the entire load capacity. Because the gauges are reading pressure from the bottom of the bore I will be able to directly jack up the trailer to the same height as the loaded ball hitch and as long as I don’t max out the stroke I will have an accurate pressure reading. Because more volume of displacement will not equal more pressure but rather extend the stroke. So to acheive my target tounge weight I will need a reading of 160.4psi (450/3.14159/.893025=160.4). With two more cheap bottle jacks and gauges I could get total weight as well very accurately but I am rather confident that I have a close enough total weight based on specs. Will post photos and results once complete.

 

[Captbob]

For what it's worth, I took my AR240 2010 to a Quarry and used their truck commercial scale to weigh the boat on the trailer. The boat had almost a full tank of fuel and the normal boating gear was on board. The weight was 5,100 lbs. I then attached the trailer and boat to my tow vehicle and got a new weight of 4,540 lbs. The vehicle was off the scale. That gave me a tongue weight of 560lbs. That should give some people a base line.

 

[Chief]

Just fyi....if you are calculating weight the fuel tank holds 55 gallons when full.
But if you are calculating range use 50 gal because 5 gallons is unusable.