Thru hull
- Thread starter SeanTX
- Start date
Nope. If anything, a bit more of the Life Seal to the base of the threads to help hold the nut securely should be sufficient.
Since the through hull has straight threads, they don't engage like a tapered pipe thread. There is always a spiral leak path. I would use the same sealant on the threads just in case. That's what I did.
I used 5200 on my Thur hull and when I also replaced 2 transducers the Airmar
Instructions said to use 5200.
The factory transducers had 5200 on them and was not all that hard to remove the unit
and I had to change the size of the hole for the new transducers.
I always use 5200 anything below the waterline and you should not need to replace
the new thru hull so water tight is needed.
I did replace all my old backing plates when I replaced 2 thru hulls and replaced the backing plates on my other 4 thru hulls all with 5200.
Nick
Instructions said to use 5200.
The factory transducers had 5200 on them and was not all that hard to remove the unit
and I had to change the size of the hole for the new transducers.
I always use 5200 anything below the waterline and you should not need to replace
the new thru hull so water tight is needed.
I did replace all my old backing plates when I replaced 2 thru hulls and replaced the backing plates on my other 4 thru hulls all with 5200.
Nick
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I use LifeCaulk on my thru hulls also. Put a liberal amount on the head of the thruhull and then a strip the length of the threads, to seal and help keep the nut from loosening.
FWIW, your thru hull has NPS (straight) threads and that valve has NPT (tapered) threads. A job done correctly will not mix the two. I know many boat builders do this, but that doesn't make it right. Use the proper adapter, as shown in MainSails thru hull article.
FWIW, your thru hull has NPS (straight) threads and that valve has NPT (tapered) threads. A job done correctly will not mix the two. I know many boat builders do this, but that doesn't make it right. Use the proper adapter, as shown in MainSails thru hull article.
Yes, with what you have so far, you would need a flange or buy a flanged valve. Visit the Groco website
https://www.groco.net/products/valves-seacocks/flanged-valves/ibvf-flange-adaptor
https://www.groco.net/products/valves-seacocks/flanged-valves/ibvf-flange-adaptor
Thanks. I see how it works now. Correct threads and you can bolt it down. Going to order now.
Many Manufacturers cut corners to cut production expenses. Sure, that setup is on a lot of boats and it lasted for how long? Doesn't make it right though. It only has to fail once to possibly sink your boat. Gate valves are another el-cheapo no-no. If you haven't been to MainSails' website, you should check it out. Tons of very good info there. And don't forget to donate if you feel his articles helped you out.
https://marinehowto.com/seacock-thru-hull-primer/
https://marinehowto.com/seacock-thru-hull-primer/
Did you by any chance replace your speed transducer? If so, what model was it? My 2009 H36 has an Airmar Speed/Temp sensor with 20-399-01 on it and I’m getting no speed and over 100 degrees of temp. I’m going to replace it, and splice it using the Airmar inline cable splice, if possible. Any thoughts on replacing that sensor?
The problem is that you WILL have to replace all thru hull fittings in the future. 5200 is an adhesive that yes, also seals; however, all you need is a sealant , such as life seal, on the threads and under the external mushroom of the thru hull fitting for an adequate seal. The backing plate and nut provide sufficient mechanical attachment. When using 5200, think hull deck joint or hull keel joint that needs maximum adhesive strength that will never need to be disassembled. Yes, with many solvents that are now available, 5200 can now be broken down with some success; however, using such a strong adhesive as a sealant just causes a lot of grief, wasted time, and expense to disassemble.