Solution for Sport Boat Ski Pylons

[oldmanram]

Hi Guys, I own a 2007 205 sport and like a lot of you I was unhappy using the center tow hook or the transom tow hooks for tubing and water skiing. They are both positioned too low, and when tubing the line will hit the wake causing a spray for the tubers. (and swimming eye goggles don't look cool enough)
This is the solution I came up with, using an EDDIE Marine ski pylon kit: It is installed in the swim step of my boat and works great. I cut about a foot off the pole after these photos were taken to minimize deflection, and it just didn't need to be that tall. EDIT: I ended up with the pole 24" above the swim step. I can say I MAY take a little more off but at this length deflection is less than 1/2" when pulling a tube. Also I have submerged a tube at low speed with no permanent pole deflection.
The black panels you see are 1/4" composite epoxied to the fiberglass to spread the load out, on the vertical part I also added a 1/4" Stainless Steel flat bar to further strengthen that area.

 

[Carpediem44DB]

Looks pretty legit to me. Nice work.
Carpe Diem

 

[Arminius]

You might wish to run the numbers. A cutting slalom skier puts a tremendous load on the top of the pylon as the skier slows all the boat's momentum and prop thrust down appreciably. Your force multiplication with the ratio of the long upper portion to the short bottom extension would make Archimedes squeal. Or just send the photos to Wiley's ski shop. They have never been hesitant to offer opinions. This is mission critical stuff where your safety factor should be 300%.

 

[oldmanram]

Thanks Carpe Diem
Arminius, You are correct, the numbers scared the hell out of me, not the skiing ones, for as you can see I don't pull that hard

Skiing an old Connely F1
BUT a tube , that gets stuck , that can pull hard !!! Estimates I saw online were in the 2000lb range if a tube submerged ,
I cut the pole so that it ended up 24" above the deck, and with about 7" in the deck it worked out to a little more than a 2:1 mechanical advantage. That's about a 4,000 to 5,000lb of momentary force. (I can't find my numbers, that's from memory last year) Anyway that's why all the reinforcing of the fiberglass, AND the SS bar stock as well, designed it as if I wanted to lift the entire boat from that one point. I figured the weakest point was the pole itself so I settled on a SOLID aluminum pole, although a thick walled Stainless Steel Pipe would have been better. And has a better chance of not having a permanent bend in it under extreme loads. It has a season on it and so far no permanent bend.
Thank You for the info about Wiley's , haven't been down there in years. Grip it and Rip it !!!

 

[oldmanram]

I mentioned that I cut the pylon down, well here are photo's of it cut down

I may cut off an additional 4-6 inches , last year I did notice that when going INTO the wind the tube would get pretty light. And I tow some kids that enjoy going FAST. I remember one time I got it so light it was "sponson walking" (google hydroplane sponson walking video)
And I tow a 3 person tube. Pretty big surface area.
The point is it still may be too high , and lowering it will also reduce the mechanical advantage thus reducing the force on the bolts.
The last photo shows the Forward Lean of the pole , just a touch.

 

[Stingrayaxe]

A 12" SS solid drop in pylon was an option on later boats. I have one and it really makes a difference. I cobbled together a flag pole that I drop in the same spot when we are not pulling a skier or tube.

 

[Arminius]

What happened to your blower manifold? Was there a special reason you did not add diagonal braces? Tough area to be working in! Looks like you did as much as possible within the limited volume. I am curious about the composite material. I am guessing you believe that it can be bonded better than metal but I see a beige intermediate layer.

 

[Arminius]

Your base is level but the exterior surface it is bolted to is angled above the outdrive. Did you pour half a bucket of catalyzed epoxy into the area under your base to get a level surface? Mine is obscured by the blower manifold.

 

[Arminius]

Wondering about a tower-arch as an alternative. Apparently not so good to ski behind. The 10' tower would be a vertical lever rotating the stern into the water. It would impede planing.

 

[Pirate Lady]

Asking because I like to learn new things. What’s wrong with the ring/hook that comes standard on the transom? See pic under the name.

 

[Arminius]

The ring and hook is fine. The standard pylon gets the rope out of the water a little more. The OP wanted some extra altitude for pulling tubes. I wondered about an arch as I see them a lot. My quick research indicated they were for boarding. I thought they might pop an old skier out of the water. Not so much if they increase the time to plane. Be a big hassle for canvas and trailering too. Good place for idiots to mount loud speakers playing loops of really obnoxious noise alleged to be music. As long as they anchor in front of the Gates residence. Or Martha Stewart's.

 

[Stingrayaxe]

Asking because I like to learn new things. What’s wrong with the ring/hook that comes standard on the transom? See pic under the name.

Pirate
The ring is a good all around tow point. Wakeboarders prefer a higher tow point like on a tower. It allows them to get more air for tricks. Skiers prefer a lower tow point but higher than your tow ring provides. This is where the shorter pylons come into play. They sort of replicate the tow point on a traditional ski boat. The difference is that the pylon on a ski boat is in front of the inboard motor like in a Malibu or Correct Craft ski boat. It changes the geometry completely. The best way to pull a tube is with a bridle attached to the transom tie downs. This is cumbersome so most will use the tow ring. Tubes should not be pulled from a tower as it creates too much stress on the attachment points and could cause the tube to get airborne. This may or may not be a good thing depending on who is in the tube. Most of the shorter pylons have a warning label against using them for pulling a tube. The pylons are also good for getting old fat men skiing old fat skis out of the water easier. I speak from experience on this topic.

 

[Arminius]

First time pulling a skier this season. Might have a bit more bow rise with the weight of the anchor I put on the swim platform. (Glad I stuck with one battery and a Blue Seas alarm/switch) I was so pleasantly surprised when she yelled "hit it" and I got a very flat strong pull with the standard hook and eye on the hull just above the swim platform. A pylon would only be a lever to pivot the stern down. The last thing you need when the boat must plane before the skier can plane.

 

[oldmanram]

Arminius , in answer to a couple of your questions posted
A: I have no blower manifold , 5.0 Carbureted Mercruiser
B: I went with a carbon fiber layered in composite epoxy , yes for adhesion to the fiberglass
C: If you look under the black composit plate , you can see that the surface was sanded down to the fiberglass, this is the hardest and most important step, you MUST get down to the glass and sand away all the paint/gelcoact for goodd adhesion. TOOK HOURS !!! Hint: Cover your motor ! and anything else you don't covered in fiberglass
D: The photo with the outdrive , the outdrive is turned , all bolt holes are squared to transom, +- 32nd of inch

I'm looking for that sweet spot as far as PYLON height is concerned :
Too low , and the when tubing it hits the wake
Too high , and when you have a large flat tube it can get pretty light at high speed
thanks guys

also on my next SeaRay I'll look for the optional pylon in the rear !!!

 

[Arminius]

Thanks for your replies. I think the engine compartment blowers are there to clear fumes from carbed boats. The float bowl has to be vented to work right. My MPI compartment never smells and the only time there would be fumes would be in case of a leak. You could open your engine compartment to ventilate it before starting after it has been sitting for a while. I put out a stranger's engine fire once with a powder extinguisher. He just frowned at the big mess I'd made. And, I've seen a few burning boats sink.
I'm really having a lot of trouble getting up on a ski and now realize a magic pylon won't help. I've decided I am not going to get any older, just meaner!

 

[oldmanram]

Arminius,
I had to revert to getting up on 2 ski's , sucks to get old, I have been deep-water single slalom starting since my 3rd day of skiing over 50 years ago. Which also meant goodbye to the double wrap boot in the rear. I went with a Connelly rear that is pretty tight, so it isn't that bad. Better than not skiing at all !!!!!

 

[oldmanram]

Update:
I cut an additional 4" off of my pole last week , I'll see how it handles skiing and tubing this week. I'll take notes on how far above the wake the line is when tubing, that way I'll have a gauge as to further modifications.
Photo's to follow:

So we went to the lake last week , and it worked great , it's a little shorter than before , but the line is still out of the water by good margin for tubing. And more importantly when tubing, the tube did NOT get light in the front as before, in fact it tracked really good, and when whipping the tube the line was not pulling up like before , the tube had no tendency to get air under it and get as light as before. As far as waterskiing it works great as well, just judging by my eye I'd say that the height now is just a bit higher than a tournament ski pylon mounted in front of the engine, of a tournament ski boat.

 

[Jim P.]

I need you to come to Alabama to install one like this on my 2007 210 sundeck

 

[Arminius]

Nice clean work. Please send us an image if modifications are required.

 

[oldmanram]

I need you to come to Alabama to install one like this on my 2007 210 sundeck

Jim, How about bringing your Searay up to Washington, judging from your weather lately (tornadoes and thunderstorms) you might get to use it up here