Thru hull fitting and gate valve replacement

[David]

My '88 H33.5 is presently in the boatyard; I am doing routine maintenance. I have one gate valve remaining that is an overboard discharge for the head/holding tank. I have decided to replace it with a new bronze ball valve and a new thru hull fitting. Any recommendations for removal of the gate valve and thru hull fitting would be appreciated. I do not want to re-kindle the ball valve vs seacock controversey!!! I am definitely using a ball vavle.

 

[Kjell Arne Nyhus]

Grind it off

To remove your old through hull you may use a rotating grinder. Grind off the outside flange andpull the valve on the inside.

 

[John K Kudera]

Definately use a grinder,

However, I reccommend you take the current valve apart, simply cut the valve in half, remove it, then cut the nut holding the thru hull, tap the thru hull out, clean the hull,replace the caulk and fittings.

 

[Cliff Ruckstuhl]

Go to the Plumbing store

What you want is called a spud wrench. It is a wrench used to take the spud fittings out of Urnals. It will going into the through hull fitting on the out side and you will need someone to hold it with a pipe wrench. You will then be able to turn off the old valve from the inside. When removing the through hull fitting it's self use the same process but use a Basin Wrench on the in side to turn off the nut. The Spud wrench tits into the through hull fitting and hold it so it will not turn. All of these fittings are brass so they should not be corroded. When you see the Basin wrench you'll go "Oh Yea Isee how it work's"Cliff H 28.5 Red Dog

 

[scott]

Hey David, question:

Is there any particular condition of your thru hull that is motivating the change out. When I switched out the gates for balls in my '85 hull last year, I left the thru hulls in place because they seemed fine. I just put a pipe wrench on the body of the gate valve and they unscrewed without turning the thru hull fitting. My guess is that your thru hull was installed with adhesive so you should just try putting a wrench on the thru hull nut (maybe wd40 it first) and see if you can unscrew it before going the grinder route. If the thru hull starts turning and you have space, put an opposing wrench on the threads of the through hull.Scott

 

[David]

Scott, Thanks for your input. I would like to replace the thru hull fittings simply because they are approximately 15 years old. I am concerned about possible galvanic corrosion that may cause weakness in the internal aspect of the fittings that may not be readily apparent. I mainly want the "peace of mind" that they are new and will not fail next time I open a valve.