Any tips on removing thruhulls?

[Guest]

Have the 2 thru hulls I want gone. But rather then smash them out I'd prefer to remove them so they can be reused by someone as they are working fine but won't in the replacement system.

 

They are gunked down with a good mastic. The wire goes to the depth transducer, the speed comes and has been taken out so only it's receiver thingy is left. They screw in/out but I'm knot to sure how hard I can whack them before they break.

 

Anyone got any ideas?

 

The water was from another hidden water tank I found under the anchor locker this morning. That's the 3rd one that was inadvertently built into her. This one also chocker with water and has been since........... who knows.

[tuffyluffy 76]

Monkey wrench/pipe wrench worked on mine without wrecking them

[Guest]

Sweet, I'll try heat, never thought of that.

 

I'd like knot to bust them given the chance as that goes against my long held recycle and/or retask programme.

 

Bit cozy for a good wrench sadly.

 

Right back to the beast now. It maybe wet but it sure isn't cold.

[rigger 47]

See if you can find an easy out large enough to work from the outside once the locking nuts are removed. Might mess up the smooth finish but that could be smoothed later.

 

Or you could build a jig that allows you to swing on them from the outside. Sort of a cap on the inside with a couple of bolts through the hole to a block of timber on the outside. Tighten the bolts (do not tighten too much or you crush the fitting) and use a wrench on the outside to try to turn it - hard to explain by typing.

[Guest]

Hacksaw/Sabre-saw them off as flush as you can get them then put the blade down the middle and put two cuts 90 deg to each other so you remove a 1/4. Then knock out the rest with a mallet.

[Norwegian Blue 10]

I replaced mine on Infiltrator last year. Unfortunately only the inside has mastic and for bugger all reason because the fittings had actually been epoxied in.

 

The only way to get them out was with a hole saw. The depth was easy because the drill guide could go into the transducer and the depth I put a wooden plug in which I sawed off flush on the hull but meant I could bore out the middle with accuracy. Once the core was out of both, they cleaned up easy.

[idlerboat 116]

..all of the above ,...at the end of the day what works works

A lot of through hulls (but not solid transducers) have two lugs on the inside. I make a plate that sits up exactly into the seacock, and engages these lugs. A very large shifter and pipe in desperate situations)can then apply a lot of force. Either clever use of tape or a second person helps. If the lugs break (bronze) or strip (plastic) its all over. Absolutely clean all surface goop and hot air gun heat.

If it goes sideways then cutting the outside flange has worked best for me. Very careful use of a 4inch angle grinder with a 1mm cutting blade on bronze and a stinky use of a very coarse flapper disc for plastic.

With plastic do a little and then let it cool or the disc will clag ....

Once the flange has been removed then I try and slice around between the fitting and hull aperture. Often they are not a tight fit (which is good because tight fits dont allow good sealing, but thats another story)...

Using a piece of pipe or large sockets if you have them (use wood between them) you then carefully tap (bash) the fitting inwards.

Pactience saves catostrophic hull damage !

 

The internal ring is often very nasty ! In the long run a home made tube spanner can save more hours than the time to make one. The hull angles internaly often make the ability to get any kind of spanner or pipe wrench almost impossible.

I have found that through hulls are too often placed in positions that are very difficult to get too.

Too close to frames, bulk head supports or other infrastucture. And a tiny offset floor hatch to get to them.

This results in seacocks never being turned on or off.

They then sieze and always open.....this defeats the whole point in having them.

SO, if you are going to the trouble....

do you need them in the first place...?

Should you glass over and relocate..?

 

Lest you think I am overstating, on a 54 footer recently only one YEP one seacock was not seized.

The most scary was a major 75mm below the water line.

This boat had recently been surveyed so ...........

[Guest]

You could just use a sabre saw and cut around them both them re glass. If it was ferro it would be so easy.

[Guest]

Use a hole saw, ( best from the outside ). Then you can place the entire fitting in a vice to cut the surrounding bit of hull away from the through hull in pieces allowing you to save the fitting for re-use.

Best done from outside so the flange doesn't get damaged by the saw.

Use the same hole saw to make a plug to repair the resulting hole. ( Helps keep the wet stuff out ).

[Grinna 2]

Here's a link to an interesting website with all sorts of "how to" articles.

 

This link points to an article about replacing through hull fittings.

 

http://www.pbase.com/mainecruising/replacing_thruhulls

[Guest]

Tried heat on the mastic, Nope.

Tried a few things and no joy.

 

So I think the plan of trying to get them out intact is looking shaky. Knot a biggie really just a shame they couldn't be reused by someone in need but ya get that.

 

Mind you for an hour or 2 yesterday I was sure the shed was going to get airborne. Hell some of those gusts were huge. I tied the whole thing down to the boat/cradle working on the theory it'll be a clusterfuck so why knot make it a massive one. Luckily the thing stayed there somehow. I did install some large 44gal drums full of water in the corners and tied it all down to that as well. The worst bit was the last 1/2 hr before the front pasted over, I was positive she was a goner but no ......... maybe I missed my career as a shrinkwrapper

[Jon 360]

KM I've found that you can't beat a FBH for this job

[Guest]

I think that looks to be the outcome D.

 

At the moment she is being cooked from the inside out so when I go back in I'll take my 15lber and we'll have a chat that I will win.

[alibaba 77]

I see you are at Bayswater, so am I, and I made a puller up last year especially for that job.

It's a long bolt which goes right through the skin fitting and two pieces of angle aluminum on the inside and outside.

You put nuts on each end, a wooden block to protect the hull, , apply a spanner.

worked on three of mine last year and you're welcome to borrow it if you like.

0121539757 chuck me a text.