Aft Above the Water Line Thru Hulls on E38

[mkollerjr]

There are a series of thru hulls on the aft port side of my Ericson 38. See photo below:



From left to right:

1. Cockpit drain
2. Propane locker vent
3. Shower bilge
4. Main bilge
5. Manual bilge
6. Exhaust



On the interior:



During the survey, the surveyor said some of these thru hulls were quality ones, while the others were cheap. Looking at the photos, I’m guessing he was referring to the far left and right ones being good quality (cockpit drain, and exhaust).

This weekend, I replaced the section of 1.5” hose from my cockpit manual bilge pump (Whale Gusher 10) to the aft thru hull. The original hose was cheap clear corregated vinyl, with white silicone gooped on and double clamped at both ends. The new hose I installed was noticeably loose on the barbed thru hull fitting, and I had to crank the clamps down hard to get it to stay in place.

I tested the pump last night by filling the bilge with water and manually pumping the pump. Unfortunately, the hose was leaking quite a bit at the thru hull fitting. I’m thinking my options are either:

1. Try to add some kind of sealant (silicone) at the hose connection to the thru-hull as before. Or…
2. Replace the thru hull with a more quality one, which the hose would hopefully fit on snugger, like on the cockpit drains (I used the same hose on those and they were hard to get on they were so snug).

Any thoughts? Is it difficult to replace these above the water line thru hulls?

Thanks,
Mark

 

[Christian Williams]

My boat came with ribbed to smooth connectors like the one at the left. I've cut most of them out by now, but they did seem to work.

 

[Loren Beach]

Another mid-80's Ericson in our moorage changed that same "row" of exits to all bronze a few years ago.
I went with SS when I changed ours, thread on this site.
If I were in your Topsiders, I believe that I would make that upgrade.

Loren

 

[mkollerjr]

Is it just a matter of unscrewing the interior part, and popping out the thru hull to the exterior, then screwing a new one in with the appropriate bedding compound (butyl)?

Mark

 

[u079721]

I never tried to replace any of ours, but I did worry about them. That's because they are ALL well below the waterline at one time or another, either when the boat is heeled to one tack or motoring at hull speed. As such they really should be bronze or Marleon quality, and possibly even have valves attached too, so you could at least close the through hull if the hose popped off or the barb broke off.

 

[mkollerjr]

previous thread

I found this thread by Loren:

http://www.ericsonyachts.org/infoex...0-Transom-Thru-Hull-Replacement&referrerid=28

Looks like they come in two pieces, and that backing part screws off. The question remains on how/what to bed them in...

Mark

 

[Shelman]

bedding for above water through hulls

I used butyl tape on my most recent above static waterline through hulls.

http://www.ericsonyachts.org/infoexchange/entry.php?233-Cockpit-Drains

I chose to use the butyl mostly because I wasn't sure how things were going to turnout sandwiching the liner and the transom together with my new through hull fittings. (some shimming was necessary)
mkollerjr doesn't have that problem but the butyl makes any future removal really really easy if needed. The other side of the coin is that adhesive sealant adds one more layer of security to hold that through hull in place. (in our minds anyway)

Just don't go crazy and use 5200.....
I'm not admitting that I did that once...
four years ago... on the sink drain....
and then had to remove the through hull four months later.

I like to learn the hard way because it helps with memory retention.

 

[mkollerjr]

Thanks! Are the old ones relatively easy to remove? Or is there a high probability that this could turn into an extended project?

I love it when a boat project goes from simply trying to replace an 8-ft piece of old hose, to talking about replacing thru-hulls. Oh well, such is boat work. It's still better than sanding dry wall.

Mark

 

[Shelman]

they might be stuck pretty good or they might fall right out.... but either way the plastic ones are easy enough to cut out.

The easiest was I have found to remove the really stuck plastic ones is to tap a wood bung into the hole from the outside and then use a hole saw of exactly the same size overall as the threads on the through hull to cut the mushroom head off and drill out the threads at the same time. then you can just chisel and chip and pry out what remains.

But if they are less stuck the easier method is to back the nut off and then stick a long bar that just fits inside the through hull and pry it up and down and left and right. this breaks all the sealant loose and you can just pull it out. be careful on both technique so you don't damage the hull.

If you are working with the stainless or bronze variety, get a piece of steel pipe that just fits inside the through hull and make cuts to fit the little notches inside the through hull fittings. Grab the pipe with a large pipe wrench and an extender bar and twist away.
Others have used a piece of flat bar and a crescent wrench or a purpose made through hull step wrench. but they don't work on the plastic ones.

 

[markvone]

It all depends on the glue

"Or is there a high probability that this could turn into an extended project?"

Mark,

I have all Marelon thru hulls and I can see that all the middle thru hulls in your picture are NOT Marelon. They are probably nylon or some other plastic. Once the backing nut is screwed off the only thing holding the thru hull in the hull is the sealant or adhesive they are bedded in. Don't know why anyone would use an adhesive above the waterline when the thru hull is held in mechanically by the nut, except that it makes them feel better! If they are glued in with 3M 5200 or something similar, you do not want to bang on them too hard and chip out a chunk of hull, trying to tap them out is the first step. I have heard of people using a hacksaw blade cutting radially to cut the thru hull into pieces that can be pulled out with pliers. I've also heard of boatyards using an angle grinder to cut off the mushroom on the outside (along with most of the sealant/adhesive). This was for bronze and is probably overkill for plastic.

My Marelon thru hulls are all the flush version and the above waterline ones are covered in gelcoat so only the inside thru-bore is visible on the outside. Mine are also pretty far down under the counter and yet they show small radial cracks from UV exposure after 35 years (see pics). They look fine on the inside and don't leak, but UV exposure is something to consider for above the waterline, even for the Marelon thru hulls. If you don't bed new ones with an adhesive, replacing them in the future won't be a big job. I just up-sized my holding tank vent this winter using a thru hull up at deck level that will get lots of UV exposure. I didn't want to have to open sanitary hose in the future to replace a Marelon thru hull so I used a stainless thru hull. It was $35 vs $12 for 1 1/2 inch, so it might be worth it to only replace the thru hulls once.

Mark

 

[mkollerjr]

Re: cheap plastic

Thanks for the tips! I should have paid more attention when the surveyor pointed out those middle plastic, non marelon thru hulls and said something along the lines of "those there are crap thru hulls". Who knows why the factory chose marelon on two of them, and sub-par on the other four.


Mark

 

[mkollerjr]

Re: max heeled water line

I never tried to replace any of ours, but I did worry about them. That's because they are ALL well below the waterline at one time or another, either when the boat is heeled to one tack or motoring at hull speed. As such they really should be bronze or Marleon quality, and possibly even have valves attached too, so you could at least close the through hull if the hose popped off or the barb broke off.

I was just reading some Nigel Calder, and he state it's an ABYC standard to have all thru hulls below maximum heeled water line be fitted with a seacock. I did a quick google image search of E38s sailing, and it's hard to tell if those aft thru hulls are below the water line while heeled or motoring. I'd think more importantly a back siphon device should be considered on these, but I'm not sure what the true risk is.

Mark

 

[Keiffer]

My boat came with ribbed to smooth connectors like the one at the left. I've cut most of them out by now, but they did seem to work.

View attachment 15739

I am getting ready to replace all of my thru hulls, and hose below the water line. I would like to go with hose that is much less rigid than what is currently installed (pretty much all black exhaust type hose). Is the hose that is pictured what you went back with? what type of hose is this?

 

[Christian Williams]

The last hose I replaced was for the manual Whale bilge pump. I used the green Shields ribbed hose from West Marine. The ribs aren't metal, but reinforced plastic, so I was able to secure them direct with hose clamps for a good seal (this at the advice of a respected boatyard mechanic).

The photo I took from the Internet. As I recall I had a hard time find the pictured connectors, which is why I asked the boatyard how they do it.

I do agree that smooth is better, but this is a big hose that snakes around a good deal getting to the stern, and has a high anti-siphon rise. It seems quite satisfactory in this application.

 

[mkollerjr]

Got the 1.5" manual bilge thru hull replaced yesterday. The backing nut came off without too much difficulty with a pair of channel locks. The thru hull part had to be pounded and chiseled out and broke into about fifty pieces. Then I had to spend about an hour picking and scraping the 3m satan glue out. I used butyl on the new thru hull flange, and it seems to have made a pretty rock solid seal. I'd budget about 2 hours per thru hull.

Mark

 

[Shelman]

remember to tighten the nut again in a few days as the butyl tape relaxes.