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Author Topic:   Calculating Weight of Boat, Motor, and Trailer
Hines Pointer posted 06-15-2006 07:57 PM ET (US)   Profile for Hines Pointer  
I need to know quickly an estimate of the boat/motor/accessories/trailer weight I tow, as I've been offered a station wagon at a great price but I'll need to use it as my tow vehicle.

I have a 1995 Montauk with a 1995 V4 Johnson 90. The boat has a stern 94-qt cooler as seat/storage, and -- being [characterized the stage of psychosexual development in psychoanalytic theory during which the child is concerned especially with its feces] compulsive -- I carry all required safety equipment and then some and a bit of fishing stuff. My boat sits on a LoadRite bunk trailer without brakes that I think Boston Whaler recommended in 1995 and looks -- if anything -- a bit oversized. I typically trailer with 20 gallons of gas.

I've tried to determine the weight, and my calculation is it's probably a bit under 1,800 pounds.

Can my rig possibly be near or over 2,000 pounds, which is the tow weight limit for the vehicle I've been offered? If it's close to or over, then I'll pass on the purchase opportunity.

Anyone willing to give quick advice? Regretably I don't have time to take the rig to a scale, given work, etc., so I need to quickly decide whether to buy or walk away. If any of you can quickly give me weight numbers for the individual rig components so I can check if my calculations are in the ballpark, I'd appreciate it.

jimh posted 06-15-2006 08:40 PM ET (US)     Profile for jimh  Send Email to jimh     
Gasoline weighs about 6.25 lbs/gallon.

According to information in another article, http://continuouswave.com/ubb/Forum3/HTML/011042.html , an OMC V4 90-HP weighs about 311-lbs.

The published hull weight of a MONTAUK c.1995 was 950-lbs.

The trailer weight may be listed on a sticker attached to its frame. If not, consult your license registration, as they often have the weight listed, If none of the above, see if you have a copy of the Manufacturer's Certificate of Origin (MSO); it will list the weight.

Chuck Tribolet posted 06-15-2006 09:14 PM ET (US)     Profile for Chuck Tribolet  Send Email to Chuck Tribolet     
We've had this discussion before, and the consensus was
2000 pounds or just below. But nobody's actually weighed
one, AFAIK.

I don't care for towing at close to the limits of the two
vehicle.


Chuck

JBCornwell posted 06-15-2006 09:30 PM ET (US)     Profile for JBCornwell  Send Email to JBCornwell     
I did Chuck.

My Montauk with Suzuki DF70, fuel, all gear that would fit and a towing cover weighed 1970lb. on the trailer.

I would NOT have towed it with a passenger car rated for 2,000lb.

Red sky at night. . .
JB

fairdeal2u posted 06-15-2006 09:46 PM ET (US)     Profile for fairdeal2u  Send Email to fairdeal2u     
What kind of station wagon? Big v8 american or a small import
4 cylinder.

If it is only rated for 2,000 pounds. forget it.

I use to tow mine with a toyota t100 2.7 liter v.4. It was perfect. It was rated to tow around 4,000 pounds.

Your rig is somewhere between 1600-1800 pounds.

TRIDENT posted 06-15-2006 09:50 PM ET (US)     Profile for TRIDENT  Send Email to TRIDENT     
A small station wagon is not the right tool for towing a Montauk.
I have towed my Montauk with a variety of vehicles over the years: Jeep CJ-7 -not enough wheelbase, felt dangerous on the highway / Jeep Cherokee 2wd, 5-spd -Montauk pushed me into an intersection in the rain once, and had a couple other close calls stopping in time, the standard tranny was a pain at the ramp / Chevy Tahoe- plenty of weight to stop the boat, room for passengers and gear and the rain no longer caused close calls / Yukon Denali XL does it even better, can pass other cars easily and with the AWD you never slip.
Hines Pointer posted 06-15-2006 10:32 PM ET (US)     Profile for Hines Pointer    
Thanks, folks, for your responses.

The station wagon in question is a Saab V6. I personally think Saab's dictating a 2000 pound tow weight limit is perhaps governed by the braking capacity of the vehicle and Saab being very conservative, as the engine power and road handling seem more than adaquate.

I currently use a Volvo 940 V4 station wagon with turbo and, while the towing capacity is listed as a bit under 3000 pounds, I literally don't feel my boat/motor/trailer when I head down the interstate to launch my Montauk on Long Island Sound or trailer it to Cape Cod, and the turbo almost never kicks in.

My sense, however, is that you fellows don't think a small V6 is adaquate power and that braking may indeed be an issue for a mid-size station wagon. Any further comments based on this additional information would be greatly appreciated, but I'm sensing my "GAM jury" is saying "no" to a 2000 pound tow limit vehicle.

Being extremely safety conscious both on the water and the road, I'm thinking I should pass up the opportunity to buy the Saab. Any further comments that might might counter this conclusion?

Thanks for your help.

Chuck Tribolet posted 06-16-2006 08:48 AM ET (US)     Profile for Chuck Tribolet  Send Email to Chuck Tribolet     
My first two Pathfinders had small V-6s (2.6L, 3.0L), and
were adequate.

The SAAB is front wheel drive, right? That can be an issue
on slippery ramps because there's weight transfer to the
rear wheels on an upslope. On the other hand, the drive
wheels are farther from the water.

No way your rig is only 1600-1800 pounds. Do the math. Boat,
motor, gas, and battery: 950+311+20*6.25+40 = 1426 That
leaves 174 to 374 for trailer and all other gear.


Chuck

Whaler_bob posted 06-16-2006 09:36 AM ET (US)     Profile for Whaler_bob    
You also have to consider the tow vehicle tire surface area in contact with the road and the total mass of the tow vehicle versus the total tow load mass. If your boat/trailer weighs in at around 2K LBS and the car is probably in the mid to high 2500-2800 LB range, that’s doesn’t seem like a very favorable ratio. Tire grip and panic stopping could be a real issue on slick/wet roads due to the narrow car tires. Also due to the FWD of the Saab, it may be very easy for the boat to swing the rear of the car out of line during turns if you apply the brakes.
I’ve always used a SUV for towing just because of the high mass of the vehicle, oversized brakes, and wider profile tires used. When I had a 17 foot center console- I had a Jeep Cherokee, now I have a Expedition for my 21 foot walk-around. I use my Honda CRV (fulltime 4WD) for my 13 foot Whaler.

The way I look a it…. think of a 300 LB wrestler, he can toss a 150LB guy around quite easily due to mass/weight ratio being in his favor. It’s a different story when he tries to toss around another guy who weighs 275 LBS. If your boat/trailer/accessories weighs close to your car weight… it may be less than an ideal match.

Tom W Clark posted 06-16-2006 09:57 AM ET (US)     Profile for Tom W Clark  Send Email to Tom W Clark     
For many years I towed my similarly rigged Montauk around with a 100 HP Toyota. It was just fine. I am sure the Saab will be too.

http://continuouswave.com/whaler/reference/whalerRepair.html#01-13

jimp posted 06-16-2006 10:26 AM ET (US)     Profile for jimp  Send Email to jimp     
About 2,000 pounds.

In 1992, in preparation of a move to another town, I weighed my 1982 Montauk with 1982 Evinrude 90, anchor, gear, coolers, spare tire on the trailer, etc, but I can't remember if the 2 12-gallon gas tanks were empty or full. The commercial scale said 2,060 pounds.

I'd be concerned about towing long distances with something rated at 2,000 pounds. Short distances, under 2 miles(?) on level ground, might not be a problem.

JimP

Hines Pointer posted 06-16-2006 11:25 AM ET (US)     Profile for Hines Pointer    
Many thanks for all your thoughtful comments. I'm backing away from the car purchase.
Hines Pointer posted 06-16-2006 10:23 PM ET (US)     Profile for Hines Pointer    
VALUABLE LESSONS LEARNED (for me anyway, and hopefully for some of you)

Curiosity was killing this cat, so I did two things even though I had already told the Saab seller that I was backing off: (1) I found a place to weigh my boat, motor & trailer with full fuel tanks and all equipment (after talking with local and state police and a couple of car shop friends I finally learned to go to a truck stop on the nearby interstate and pay in my case $8.50 to use their scale, typically available 7X24) and I did it; and (2) I called Saab and finally spoke with technical folks who knew what they were talking about and got some shocking information.

What I learned was the following:
(1) my boat, motor, trailer, full tanks (20 gallons) and equipment weighed in at 2,190 pounds -- the truck stop scale weight was 2,060 & tongue weight an additional 150 pounds. I clearly underestimated the usual boating equipment I carry by over 400 pounds, as I knew the other weights involved.
(2) while the Saab owners manual stated that towing capacity was 2,000 pounds, information in the Saab parts manual at my local Saab dealership relating to trailer hitches CLEARLY STATED that all Saab sedans and station wagons have a maximum towing weight of 1,000 pounds for trailers that don't have brakes. What does this mean? It means that the major factor in determining towing weight capacity is not pulling power, but rather braking capacity. The Saab folks stated that, while braking capacity is most critical with front wheel drive vehicles like Saabs, anyone wanting to effectively determine towing capacity for a vehicle needs to check both the owners manual AND information in the manufacturer's parts manuals dealing with trailer hitches, the local dealerships service department, etc. -- evidently this discrepency is not unusual, and one has to go with the lowest number stated, given trailer characteristics.

The lessons I take away from this experience:
(1) Go to a truck stop or elsewhere and pay a few bucks to use their scale so you know accurately what the weight of your rig is -- it's simply good information to know for a variety of safety reasons.
(2) Don't trust just your vehicle's owner's manual or manufacturer's advertising to determine your vehicle's towing capability. Talk with folks in the parts department who supply the manufacturer's hitch equipment AND the manufacturer's technical service reps to see what they say about towing weight maximums.
(3) If you're buying a trailer for a boat you plan trailer long distances and on interstates, seriously consider surge brakes. I quite honestly never imagined trailer brakes were necessary for my '95 Montauk, as the boat is so much lighter than my previous 20+ foot center console boats, but now I understand that a trailer without brakes can really affect tow vehicle options.

I'll stop, as I've been more that long winded. Probably some of you knew everything I written and many of you knew some of the points I've made. But, as one who is very safety conscious both on the water and on the road, I really hope that this information has been eye opening for some folks who -- like me -- are quite ignorant about this and thus might be at risk.

fairdeal2u posted 06-17-2006 02:17 AM ET (US)     Profile for fairdeal2u  Send Email to fairdeal2u     
My montauk with a lighter trailer didn't have surge brakes and I never had much trouble with a 4 cylinder toyota t100 truck.


My present rig with a bigger boat has disc surge brakes. They work great and will actually slow down the truck. I neve felt the need for them on the montauk. But for this boat that is about the same weight as a 18 outrage...the brakes are necessary.

macfam posted 06-17-2006 08:16 AM ET (US)     Profile for macfam  Send Email to macfam     
I don't really want to admit this, but 25 years ago I towed my Nauset, w/70 Merc with a tiny Plymouth Arrow.

A little 2 liter, 4-banger, 5 speed manual.
When you were following me, the Nauset would completely obscure the car. Really funny.

More than once, people at the boat ramps would ask, "Is that car really going to pull that boat out?"

It never even strained.

Was it safe?........NO, but it was all I had at the time.

Did it do any damage to the car? Well, I sold the car with 205,000 miles on it. It was still running like a champ!!

davej14 posted 06-17-2006 12:06 PM ET (US)     Profile for davej14  Send Email to davej14     
I think a lot has to do with the type of trailering you anticipate. If you are talking about a local trip to the ramp or relatively flat terrain then you don't need a gas or diesel guzzling behemoth to tow your relatively small boat. If you are planning for long trips over hilly geography then that is another matter. That SAAB wagon would have been fine for typical tows. I use an older V70 Volvo wagon, that has less torque, and pull a boat with similar weight. I hardly know it is behind me except on steep grades and never felt braking was an issue. My second vehicle used to be a SAAB 9-5 sedan which I also used to successfully pull the boat on a regular basis.

Don't expect a manufacturer to generally endorse any activity with their vehicles in this litigious society.

gnr posted 06-17-2006 12:18 PM ET (US)     Profile for gnr  Send Email to gnr     
Thanks for the info HP.

Thanks also for doing the research and putting yourself in safe vehicle.

Weight ratings are as much marketing tools as anything else.

Simple common sense tells us that the tow vehicle should weigh much more then the trailer being pulled just to avoid the tail wagging the dog senario that would likely happen in the case of an emergency.

It's not about the pulling, it's about the stopping and the handling.


Hines Pointer posted 06-17-2006 10:25 PM ET (US)     Profile for Hines Pointer    
Thanks for your recent great replies, folks. Based on them and the prior earlier information from the thread of this discussion, I'm coming away with I think a few basic points that are important for me, and may be valuable for others of you:
(1) first and foremost, go out to a scale and weigh boat/motor/trailer/accessories to know the accurate loaded weight of the towing rig;
(2) when buying a new tow vehicle, check the vehicle manufacturer's owner's manual for towing weight maximum, and then check with the dealer's parts department to check the manufacturer's specs regarding maximum weights associated with the towing harness that will be installed on the vehicle; and
(3) finally, before purchase check with the manufacturer's web site resources, other Internet-based resources and resources like this great forum of folks who give lots of insights about the subject.

The bottom line here is safety on the road. If trailer brakes are waranted for the vehicle we want to buy, then buy or add them. If a new tow vehicle is in mind, then do the homework above.

I've seen some horrendous accidents on the interstates that probably were the result of inappropriate towing combinations or not proper maintenance of the trailer. Let's all be overly careful, so we enjoy both our time on the water and getting to it.

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