thru hull fittings

[gatehopper]

I am looking at changing the thru hull discharge valve for my black water holding tank on my 1986, 3297 Mariner. I does not look very healthy. Can any one offer any insight. I will hire a pro for the job but would like to know about any common issues that might arise.
Thanks Gatehopper

[waybomb]

I replaced all the through hulls on mine with solid stainless steel ones.
The hardest part is getting to the backside of some them, but they were all accessible.
It is not difficult work.
But it scratch-up-your-arms work! A few choice words come out of nowhere as well.

[gatehopper]

Thanks Fred, This one is located directly under the hatch cover in the forward state room so lucky me. Thanks Gatehopper

[waybomb]

You'll want to bed the the fitting in 3M 5200. Wear gloves.
Also, I set the fittings in the hole, then taped around the fitting. Pulled the fitting out, and taped the visible part. The applied 5200 to the backside of the flange.Tightened the nut up, and simply wiped the oozed-out 5200 from the tape and removed the tape. No clean up of 5200 from the hull this way, or the fitting.