adding ski tow to old boat

[david_r]

this is the first boat ive owned that i thought was big enough for pulling tubes, etc... i was wondering if anyone could give me advice on which type of the devices to install on my boat.

1978 venture, rendezvous 3 -16.5 fiberglass- 1979 115 johnson

shes old and she aint too pretty but she only weighs 830 dry, and she gets up and goes pretty good, just wondering about doing any structural damage to a boat that old using a transom tow vs tow tower(the thing that goes into your rear seat pedestal, not sure what its called).

thanks for the help!

 

[NelsonQ]

Re: adding ski tow to old boat

I had an older fiberglass runabout that I did this with but the simplest solution for towing is to add a self centering tow harness (http://www.airhead.com/2008/ahth3.php) to the back of the boat (where most connect their transom straps to when trailering) and from there connect the rope from the harness to the towable.

The harness does several things.

One, it keeps the rope out behind the outboard so it doesn't get caught up in the propeller/lower unit.
Two, it self centers as you turn the boat to prevent uneven load on the back and slack in the line by always centering and keeping even tension.

One caution is that I learned was I would drag in the tube to change riders but when to push out the next rider watch that you don't get the rope/harness looped around the steering rod on the outboard from the slack pulling it in.

 

[david_r]

Re: adding ski tow to old boat

thanks for the advice, the kids will be excited, i thought it was going to cost me an arm and a leg. did you beef up your transom or just watch her kind of close fo a while?

thanks again!

 

[NelsonQ]

Re: adding ski tow to old boat

Mine was a 1972 14.5' runabout and i didn't do anything extra.

Simply inspection of the boat and the quality of the rings on the stern of the boat should be enough. (ensure they're not loose or worn and that the overall integrity of fiberglass.)

As for it pulling it, I pulled a single rider tube with my 10yr old with ease on a 65' Merc 50HP. I also pull a extra large two rider tube with two people and 4-5 in the boat on my current 17' with a 115HP with no problems so your boat with that engine, should do great.

That harness for reference was $30 here in Canada. Just ensure you match your rope as well (ensure you have a 2 person rated rope for 2 persons) You can never have too heavy a rope.

Hope it works out for you. Kids love it.

 

[kenmyfam]

Re: adding ski tow to old boat

Mine was a 1972 14.5' runabout and i didn't do anything extra.

Simply inspection of the boat and the quality of the rings on the stern of the boat should be enough. (ensure they're not loose or worn and that the overall integrity of fiberglass.)

As for it pulling it, I pulled a single rider tube with my 10yr old with ease on a 65' Merc 50HP. I also pull a extra large two rider tube with two people and 4-5 in the boat on my current 17' with a 115HP with no problems so your boat with that engine, should do great.

That harness for reference was $30 here in Canada. Just ensure you match your rope as well (ensure you have a 2 person rated rope for 2 persons) You can never have too heavy a rope.

Hope it works out for you. Kids love it.

A 4 person tow rope is about $5 more and gives a lot of peace of mind.

 

[david_r]

Re: adding ski tow to old boat

on this quick inspection. i have found no cracks anywhere on any of the transom, and this includes triming her out and practically laying on the lower unit, but i can grab the rings and tug and pull and the transom flexs some. is this normal?

this is my first fiberglass boat and i dont want to rip any holes in the transom because of fatigue, and im a little cautious about my new (to me) toy.

i only gave $400 for the boat, trailor, and motor. it was deffinatley what you would call a fixer upper.

thanks for the help.

 

[metriccrescentwrench]

Re: adding ski tow to old boat

...but i can grab the rings and tug and pull and the transom flexs some. is this normal?

Maybe someone else can chime in, but that part doesn't sound right. I've got a 14-1/2 ft fiberglass boat built in 1981 with a 90 HP Johnson and pull skiers and tubes using a tow harness fastened to the tie down rings as mentioned previously. I can tug on those rings with all my might and there's not a bit of give anywhere.

 

[NelsonQ]

Re: adding ski tow to old boat

I'd have someone more experienced check if you're unsure. I certainly can't see any flex grabbing on these rings.

You may have some transom issues you should resolve/reinforce before hooking anything to it. With the drag of the tube in the water with a person or two, you're going to be putting the equivalent of a few 1000 lbs of load on it. Doesn't sound from your description it would support it.

Have the transom inspected first.

 

[david_r]

Re: adding ski tow to old boat

ok i put a wrench on them and they were a little loose, now they dont flex anymore but now there is a .25" crack next the port side ring. looks like its just a paint crack.did i overtighten or is this a prob too?

any tips on how to reinforce transom?

can i just get some longer threaded rings and just add some support on the inside w/wood?

maybe i should be asking this question on the "boat repair" thread?

thanks for the help!

 

[kenmyfam]

Re: adding ski tow to old boat

ok i put a wrench on them and they were a little loose, now they dont flex anymore but now there is a .25" crack next the port side ring. looks like its just a paint crack.did i overtighten or is this a prob too?

any tips on how to reinforce transom?

can i just get some longer threaded rings and just add some support on the inside w/wood?

maybe i should be asking this question on the "boat repair" thread?

thanks for the help!

Stainless or Aluminum transom reinforcement plate that fits right over the transom would sure help, however you need to make sure your transom is in good condition first.

 

[david_r]

Re: adding ski tow to old boat

thanks guys i appreciate all the advice.

i will have it checked today since its finally friday..woohoo!

 

[metriccrescentwrench]

Re: adding ski tow to old boat

Before you said you could pull on the tie-down rings and the transom flexed, then after tightening the rings it seems ok. Did you mean that when you pulled on the rings they'd exhibit some movement? If that's the case, and there's no motion after tightening them then you're likely OK. You should be able to push or pull anywhere on the transom without it showing any sign of movement or flex.

One thing to do would be to take a quarter and tap-tap-tap all over the transom. Any areas where the sound is different (kind of like a dull thud) you should take the blunt end of a screwdriver and check for softness.

That small crack that showed up after tightening the tie-down ring is likely just cosmetic, but do check that area over for structural integrity from time to time.

 

[walk-on]

Re: adding ski tow to old boat

I bought a ski pylon for my 17 foot runabout.
http://www.iboats.com/Swivl_Eze_Run...18850867--**********.815468641--view_id.49433
I do have a splashwell on my boat where it is mounted. When I started out I used the self centering tow harness but some people had a hard time getting up on the wakeboard so I bought and installed the ski pylon.

I am pleased with the ski pylon and it does not move at all where it attaches to the fiberglass. I was hesitant at first because I could picture in my mind how it would rip out a big whole in the fiberglass.

I'd be surprised if you're putting a few thousand pounds of load on the back of the boat from tubing but you'll definitely want to check the transom for soundness. I just replaced my rotten transom last summer.

Another complaint I've heard about using the hooks on the back of the boat is water splashing on people from the rope dragging in the water. I never tubed with the rope but it is definitely not an issue with the ski pylon as you can see by the picture of my buddy on the tube.

I don't know if it's worth a couple hundred bucks, but I'm glad I have it on my boat.

 

[hemidoc]

Re: adding ski tow to old boat

I just bought the Airhead self-centering-tow harness at WalMart for 10 bucks Get 'em while they got 'em. Also got an Airhead 60' tow rope for 10 bucks

ETA These are 4 person units

 

[fishie]

Re: adding ski tow to old boat

I also have an Airhead tow harness, I'm slinging my tube around with my little 14' 35hp mirrocraft! Tow harness is worth every penny! Just check the strength of your transom and you shouldnt have any issues! Have fun and be safe!