Boat weight references

[ozscott]

Hi all,

I know we have had boat weight threads, but I wonder if posting up pics and the weights as weighbridged might be a helpful reference point for people considering what boats to buy (and bearing in mind that the trailer plates often dont reflect true weight). Everyone would need to weighbridge to be confident when around 19-22 feet say in glass as to whether they are under or over the 2 tonn mark. Apart from a reference point (which might be only a very rough guide) I think a thread like this would be interesting. Anyone posting would try to include as much as possible about fitout and trailer type.

I will kick it off - my boat is a Seafarer Vagabond Mark 1. 115 Yamaha 2 stroke V4; 2 batteries; electric anchor winch and trailer winches (spectra rope); 160 litres of fuel (and about 100 on the day it was weighed); home made multi roller trailer which according to the plate is 400kg (13 inch steel wheels); 16 pound Mason Plough; 5m of 6mm chain; no eskies etc when weighed.

Boat and trailer weighed in last week on the scales at 1785kgs. I have heard many times that my Vag would be over 2 tonns, but the Mark 1's were not 21 footers and they were not as beamy as the later ones. They were 19 foot 8 inches from stem to stern - so not taking into account the sprit and motor. Very solid boat with thick glass all over the shop. Side Crop.jpgrear crop1.jpg



Cheers

[thylacene]

Threw our 6.3m Caribbean Reef Runner over the weigh bridge about a month ago. 2400Kg BMT which was a bit of a surprise, and now planning the brake upgrade.

Caribbean state the hull at 1020kg, engine 235 with oil, 480 of trailer, 100l fuel, (205 capacity), and fitted with anchor winch, 8m x 8mm short link chain, 9kg plough, rocket launchers, gaff rack and built in esky, and a small bucket of lead. Gets up there quickly.

FYI, about 4k in round figures for the brake upgrade, happily the axles have both hydraulic and override caliper mounts, so no welding required. The new brakes will add another 40kg

So on that basis, about 1900 kg on the water before adding people.

With the tow vehicles at 2500kg, add 150lt fuel, gear for four, and four fat fishermen, we are bordering on 5.2 tonne all up towing down the highway.

Cheers

Thy

[Moonlighter]

One thing to add guys would be whether the weighbridge weights you are posting are with the trailer attached to the towbar, or disconnected.

This helps with the ATM and GTM figures, and also shows how much weight is being carried on the towbar, as you know that is quite important too because all car manufacturers will state a max towbar downforce.

Just to refresh the memories:

ATM = Aggregate Trailer Mass, and means the combined weight of the trailer and the load it is carrying, when it is NOT COUPLED TO A TOW VEHICLE.

GTM = Gross Trailer Mass, and means the combined with of the trailer and the load it is carrying WHEN CONNECTED TO THE TOW VEHICLE.

GTM will therefore always be less than ATM because some of the weight of the trailer will always be transferred to the towing vehicle thru the tow ball.

All trailers built since 1989 have to have a compliance place with, amongst other things, ATM stated on it. Some state a TARE weight, which is the bare weight of the trailer itself.

Cheers

ML

[ozscott]

Thanks fellas - yep my mates Mark 1 Reefy is 2.75 with the new V8 etc.

Mine is trailer off the truck and only it on the bridge.

Cheers

[Chimo]

Perhaps it might be interesting to also include the details off the tow vehicle rego label too.

eg 4.2 Patrol
GVM (Gross Vehicle Mass) 2800 kg
GCM (Gross Combined Mass) 5300 kg

So the trailer (BMT)on the Patrol makes up the difference between the two ie
GTM (Gross Trailer Mass) 2500 kg. (max)

Cheers
Chimo

PS the trailer is a Seafarer Tinka with 14" wheels and Hydrastar /Carlisle electric (battery on the trailer) over hydraulic breakaway unit on which sits a Vag with two 115s OMCs

[thylacene]

When I weighed our Reef Runner I took three measurements.

The first the combined vehicle mass, empty vehicle and trailer with boat as described

4950kg

I then ran the vehicle forward leaving the trailer only on the weigh bridge

2170kg

I then put the dolly wheel down on the weigh bridge and detached it from the vehicle

2400kg

Tow vehicle is a 2010 diesel VX Prado

Specs from Toyota
Note: Kerb, tare & payload weights are nominal and will vary depending on options and tray/body type.
Weights
- Kerb weight (kg)2435
- Gross vehicle weight rating (kg)2990
- Gross combination mass (kg)5475
- Gross trailer weight braked (kg)2500
- Gross trailer weight unbraked (kg)750
Note: Towing capacity subject to regulatory requirements, towbar design, vehicle design and towing equipment limitations. Ask your Dealer for details of Toyota Genuine Towbar capacity and availability.

So doing the maths, our boat fitted out and carrying the stuff we always take, less rods bait and food/drink is 2400 less 480 trailer equals 1920 less 100 L of fuel leaves about 1820. From that I took 235 for engine and oil, and the manufacturer spec of 1020 for bare hull and another 40 for water left 525kg of gear and fitout. Estimating 100kg for lures, jigs, tackle box, downrigger bomb and sinker bucket, that is still 425kg of fitout, I honestly don't remember putting that much in but it happened, and the factory options contribute also rocket launchers and seat box I suppose, and a hefty anchor chain and 9 kg anchor & winch. In retrospect, as I type, there is some 14m of 2 B&S cable and several 30a runs at half that length for bilge, deck wash and bait tank, the list goes on.

I would recommend that everyone take a trip to their weigh bridge at least once, it is the easiest way to get the weight distribution right, and to understand how to stay within the regs. As stated, $4K for brake upgrade and re-rate the trailer, and that is just parts, with me doing the fitting.

Such knowledge may influence purchasing and modifying decisions, even as simple as the length of anchor chain. Yes I could run smaller, but there are so many compromises or extra work to get it back under 2000kg. It shoudl definitely influence which tow vehicle you choose.

Cheers

Thy

[rhodesey]

Boston Whaler 235 Conquest 2005 model on trailer 3.2 tonne.
Peterson aluiminium trailer, 300 litres of fuel, 250 Mercury Verado.

[Gon Fishun]

Haines Hunter V16C 1982, Evinrude 115hp V4 1985, Mazda BT50 2door manual.
3058 KG Mazda tow vehicle GVM
3000 KG tow rating.
3280 KG combined weight. Boat and tow vehicle
1180 KG BMT. with jockey wheel down, off tow ball.
1100 KG BMT attached to tow ball.
80 KG tow ball weight, ( a bit light).
1160 KG on the steer.
1020 KG on the drive.
2120 KG steer off the weigh bridge.

These weights are without the esky, bait, berley and tucker box.

Bobs0188.jpg

[Mister]

80kg is way to light.

Hard to find specific manufacturer ratings for many vehicle tow bars these days? Re Prado above. Even more difficult are the manufacturers that vary towball weight depending on towing weight.

[tassjo]

hi in general the max towball weight is 10% of the max towbar capacity eg my falcon has a max of 2300kg ,ball weight is 230 ,hope that helps

[Gon Fishun]

As Mister said way to light. Strange as it seems the boat tows like a dream, no swaying at all.
I am in the middle of changing the winch post configuration and would have liked to move the boat forward 100mm as the back rollers sit right under the transom, which is not a problem. So the boat will sit in its original position and will add steel to the reconfigured configuration, and will be fitting a spare wheel, spare hub and bigger anchor to the front and move the winch post forward. All in all it will probably increase the weight by 50- 80 kg with the tucker box etc in the cab.

[Gon Fishun]

hi in general the max towball weight is 10% of the max towbar capacity eg my falcon has a max of 2300kg ,ball weight is 230 ,hope that helps

I could stand corrected here, but isn't it 10% of the towed weight. EG. 1000kg towed 10% = 100kg on the ball.

[Fed]

I recently read that the so called 10% 'rule' was debunked in Europe, they say 5% is a more suitable ball weight.
My own personal experiences (non-googleboy) confirm this is true.

[tassjo]

the 10% rule is the max ball weight,just to clear it up so this post stays on track(weight of boat not towbars or balls).The specs i have qouted are from 1 of the most recognised towbar manufacturer in the country (hay ree you no what i mean.the company that i work for sell this product so yes i have some insight.

[Gon Fishun]

the 10% rule is the max ball weight,just to clear it up so this post stays on track(weight of boat not towbars or balls).The specs i have qouted are from 1 of the most recognised towbar manufacturer in the country (hay ree you no what i mean.the company that i work for sell this product so yes i have some insight.

In my owners manual it states, 10% of the towed weight and to use levellers if weight on tow ball is over 75 KG.

Below is off the RACQ web site.

Got me buggered mate.

Trailer Ball Load

Ball Load is the amount of weight the fully laden trailer imposes (vertically) on the tow bar of the tow vehicle.

There is no requirement to list Ball Load on the trailer’s plate, however if the plate lists the trailer’s Gross Trailer Mass (GTM), the difference between the ATM and GTM will be its Ball Load.

Ball Load, like other towing specifications, must not be exceeded.

Ball Load is not usually a critical issue with small trailers unless the tow vehicle has a low Ball Load specification, as is the case with many small cars and some European vehicles. However heavy trailers such as horse floats and caravans often impose quite high Ball Loads on the tow vehicle.

Ball Load is a function of the trailer’s axle position and the manner in which the trailer is loaded.

Ball Load can be measured at a weighbridge by disconnecting the fully laden trailer from the tow vehicle and resting only the trailer’s draw bar (via the jockey wheel) on the scales, or with special ball mass scales.

Ball Load is often around 10% of the trailers ATM however this should not be relied on for every trailer. Where no reliable information is available, the fully laden trailer must be weighed to determine this specification.

Tow vehicle specifications
Towing capacity

A vehicle's towing capacity is determined by its manufacturer and is based on factors such as the design of the vehicle, the vehicle's rear axle load, the capacity of its tyres and the effect the laden trailer will have on the vehicle's attitude and stability.

Safety and vehicle durability are also important factors. The maximum trailer load will be specified to ensure the combination is controllable at all times and that it will not adversley affect or significantly shorten the life of the vehicle's body and mechanical components.

Vehicle handbooks generally provide the following information:

The maximum weight of the trailer, without brakes, that can be towed by the vehicle,
the maximum weight of a trailer with brakes that can be towed by the vehicle, the
maximum tow ball load, and
any conditions relating to towing or additional equipment required.

This information is essential to the selection process. The specifications provided represent the absolute limits the vehicle can safely tow.

While towing specifications and recommendations are contained in the vehicle owner’s manual, to make comparisons easier, RACQ Technical Advice can provide this information for a range of popular vehicles.

Tow ball load

Tow Ball Load is the proportion of the trailer weight that is applied to the rear of the tow vehicle.

A vehicle’s Ball Load specification will be found in the vehicle’s handbook and will be listed as a weight in kilograms or as a percentage of the trailer’s ATM.

Ball Load specifications are often around 10% of the maximum towing mass specification, however this isn’t always the case. European vehicles in particular can have quite low allowable Ball Loads in relation to their towing capacity.

Too little Ball Load can cause the trailer to become unstable and too much can be detrimental to the tow vehicle’s durability as well as affecting its stability, steering and braking.