boat transom drain tubes- need help

[rfuerst911sc]

Need some opinions on what to do. Boat is a early 70's Whaler that I am rebuilding. I am at a point where I will need to install new drain tubes in the transom. If you look at the pic the top hole is for the engine well and is aprox. 3 " long. The bottom hole is aprox. 12 " long and is the main drain for the interior of the boat. Both holes are 1 " diameter. Originally Whaler used brass tubes and they are still available but to install them you need to either purchase a special flaring tool or come up with some home made rig to flare the ends. For this one project I'm really not interested in going this route. So what else is available ? I'm thinking some type of plastic or stainless steel. The trick is how to seal the ends ? I need to find some pipe that has either internal or external threads and then matching flanges that screw on/in to the pipe that can be sealed with caulk against the hull both inside and out. Any suggestions ?

[drcoastline]

Any through hull fitting will work. They come in brass, stainless, chrome over molly, plastic. I personally change all my bright work to stainless. It's not as shiny as chrome but last forever with very little work.

You will want to gouge out the core in the hole and seal it with epoxy to prevent any water infiltration to prevent rot. Bed the through hull in 3M 4200 compound and hand tighten. at the 4200 cures for 24 hours tighten furhter.





In the event you want to use the original brass fitting you don't need the tool. One end is already flared. Butter the tube with some 5200 put it in the hole, let the 5200 set overnight. You can use a large peening hammer to roll the other edge.

The boat is looking good. Good luck.

[balleta]

PVC

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[Hard-Deck]

I'm a lifelong sailor. Drcoastline has it right. My only differing opinion is to tighten once. Not twice.

[VincentVega]

Agree with above. Dont use brass though, bronze is the way to go.

[rfuerst911sc]

drcoastline so those ss through hull fittings are available 12 " long ? Any specific vendor to purchase from ? Thanks

[tevake]

I am in the tighten twice school, if you use washers. If no washers then re-tightening will shear the adhesion between the fastener and the surface.

It is standard practice in foam core to drill the hole to size, then remove the surrounding core material 1/4" or 3/8" ( more in large or high load holes.) then fill the removed material with epoxy, let set, then re-drill to size. The epoxy filler seals the core from water and allows the fastener to be tightened well with out crushing the surrounding core. You can make a tool for removing the core using a nail. Bending the head end to 90 degrees at the required depth. Then mount in a drill and trim away. I have used a thin piece cut off of a squeegee to apply the epoxy inside the hole

This sure does present a challenge in your one foot long hole. How to reach the core to trim and fill in the deeper parts of the whole.

I'll be interested to see what ingenious ideas come up here.

BTW the boat does look very nice with the new interior pieces, well done.

Cheers Richard

[tevake]

Another thought is to use PVC. Drill the hole, butter the PVC with epoxy insert PVC section that extends beyond the hole at both ends. Then sand down the ends beyond flush. Then glass over the ends and the surrounding area, and drill to the ID.

Cheers Richard

[drcoastline]

Originally Posted by rfuerst911sc

drcoastline so those ss through hull fittings are available 12 " long ? Any specific vendor to purchase from ? Thanks

Try Jamestowndistributors.com. The Marlon (plastic) through hulls will come in 12" lengths and be reasonable in price. Any of the metal are going to be crazy expensive. If for some reason you run into a problem getting a 12" through hull buy 2-6" and put them in back to back. Same process basically butter the shafts with 4200 and slide it in the hole one from each side. Slide a dowel in the hole to keep the two shafts aligned. After the 4200 sets they ain't coming out with out cutting them out. So don't worry about failure or water infiltration. If you want to be ultra positive they are stuck use 5200 bedding compound.

I would agree with the tighten once theory with regular caulk, silicone, gasket compound. Not so with 4200/5200. 4200 is 1000 times more tenacious than any of the other products and 5200 is 100 times more than 4200. No worries about breaking the bond. Trust me. When using these two products you want to hand tighten so the compound just begins to squeeze out all the way around the flange. This way you know you have a good seal. Let the compound set then give a little tighten to set the nut.

If you use two 6" through hulls back to back use caution with the dowel. If the 4200/5200 gets on it it aint coming out. Maybe wrap it in suran wrap or plastic drop cloth so you can get the dowel back out.

[drcoastline]

Originally Posted by tevake

I am in the tighten twice school, if you use washers. If no washers then re-tightening will shear the adhesion between the fastener and the surface.

It is standard practice in foam core to drill the hole to size, then remove the surrounding core material 1/4" or 3/8" ( more in large or high load holes.) then fill the removed material with epoxy, let set, then re-drill to size. The epoxy filler seals the core from water and allows the fastener to be tightened well with out crushing the surrounding core. You can make a tool for removing the core using a nail. Bending the head end to 90 degrees at the required depth. Then mount in a drill and trim away. I have used a thin piece cut off of a squeegee to apply the epoxy inside the hole

This sure does present a challenge in your one foot long hole. How to reach the core to trim and fill in the deeper parts of the whole.

I'll be interested to see what ingenious ideas come up here.

BTW the boat does look very nice with the new interior pieces, well done.

Cheers Richard

Richard, this is the process Is was aluding to when I suggested biggieng out the core and filling with epoxy.

It has been awhile since I worked on one of these little whalers. So I can not recall exactly but back by the transom where this through hull goes in may be solid fiberglass. I know the rest of the hull is full pf expanding foam but this area may be solid.

[tevake]

Right on Drcoastline, I was just trying to fill in some details for our friend in Ga.

I also haven't been around the small Whalers in so long that the details of the transom construction are fague to me. The foot long detail for the hole does have me a bit stumped.
A solid glass structure would make this a lot easier for sure.

Maybe we will get some more pics for clarity. Rfuerst911sc Has done such a nice job on the boat so far I'm sure this will come out fine too.

Cheers Richard

[rfuerst911sc]

Well after doing some more web searching it looks like the standard over the counter brass tube for Whalers is 1 " x 14 ". Not sure if the 14 " is just added insurance or what. Anyway I found a guy that suggested instead of buying the 45.00 flaring tool use a bolt and a nylok nut. When you buy the brass tubes one end is already flared, generally this goes to the outside. He then suggested using a long bolt or threaded rod. On the outside a large flat washer and nut. On the inside you use the nylock nut but install it backwards so the rounded portion will start to flare the tube as you tighten it. Tighten it as far as is safe to not crack the fiberglass, if additional flaring is needed it can be done with a hammer. Most guys use an o-ring and sealant on both ends. This sounds like a reasonable way to go. The bottom hole has wood from the transom in some of it the balance is flotation foam. I guess my only concern is what are the chances of the end I'm trying to flare to crack ? The tubes are also available in aluminum, any thoughts on aluminum vs. brass ?

[rfuerst911sc]

And here is a pic of the inside, this gives you a better idea of why the hole is so deep/long. It's not a great pic but you get the idea, the bottom hole is at the bottom of the fiberglass engine well.

[drcoastline]

That's right the deck drain runs under the motor well. The area is not solid fiberglass. The cavity is foam filled.

I believe I saw in here some place you used this boat on a lake? If that is so aluminum or brass won't mater. However, the aluminum is going to be far more susceptible to corrosion in salt water. If the price isn't much different and I can't imagine it is stick with brass then you are safe. The tube fits several models and needs to be trimmed depending on the transom. You will want to trim the tube back to about 1/8" past the transom. When you roll the lip it will push against the transom and pull tight to the trasom.

[rfuerst911sc]

I have yet to put this boat in any body of water but I seriously doubt it will ever go in salt water. But I think I'll go with the brass tubes. On the Whaler forums a lot of guys bed these tubes in with 3M 4200 or 5200 caulk. From what I understand of those products it would be VERY difficult to remove the tubes if either product is used. Do you think I should use such a permanent type of caulk ? When I had to remove the old brass tube it took me about 20 minutes and it was out, but it was corroded. If I ever have to remove the new drain tubes I don't want to damage the transom in doing so. Thoughts ?

[drcoastline]

5200 is a permanent bond. Developed to bong the hull to the liner. 4200 is a semi-permanent bond but that's not really an accurate statement. It's not as tenacious as 5200 but it is by no means semi-permanent in my book.

There is no reason you should ever have to take the tube out until it rots and that will be some time around 2053. But if for some reason you do need or want to remove it there are several options. A 1" spade or 1" hole saw will rip right through the thin wall metal in a few seconds.

4200 is the best product for the job. You could use silicone or caulk but they will fail and leak and then you will need to repair the area. The reason 4200/5200 is being used is it is the best product for the job. 4200 is perfect for this job 5200 is over kill.

You could make or buy a 1" diameter fiberglass tube grind back the glass on the hull insert the tube in the hole and glass it in place.

[unclebilly]

The thru hulls posted above and below the waterline sikaflex.

[tevake]

What ever you use. Plan to mask off the area and wear gloves!
I also like the 3M 4200/5200 products. But they can be messy.

I'm wondering if a torch heating the tube could ease removal?

Cheers Richard