Holding Tank Fitting - Bavaria 37 2007

[tomgaeb]

Hi,
I noticed a slight leak at the bottom drain fitting of the holding tank on my B37 (2007).
The material seems to be bronze or brass and it is heavily corroded.
I could not figure out how this metal fitting is attached to the tank, nor how it can be removed and more important which and how a new one fitted.
Any help very much appreciated !
Thomas

[dawntreader]

I believe the fitting you are referring to is the one where the 38mm outlet pipe is connected - between the outlet valve and tank? if so, this outlet is bonded into the holding tank and is not serviceable. However, by removing the outlet pipe and cleaning the fitting it should be ok underneath the corrosion. You (obviously) have to address the leak to prevent it happening again

[Yngmar]

Mine from 2001 is also a standard brass (not bronze) fitting in a plastic tank. It seems to be fitted with a simple metal backing nut inside the tank and some unidentifiable sealant. The backing nut is only accessible from the top inspection hatch (after removing the tank) with a very long extension. Since I didn't have a suitable size socket wrench with long enough extension, I just cleaned up the outside of the brass fitting with some sandpaper and a Dremel, abraded an area on the HDPE tank around the fitting and then gooped copious amounts of Sikaflex adhesive sealant onto both. Wait a few days for it to be cured through before causing movement or filling the tank. Total bodge, but hasn't leaked since :-)

Edit: If you want to do it properly and your tank is like mine, you'll need to remove the tank, clean it up and then find a suitable size socket and long extension to install the new fitting.

[tomgaeb]

Thanks for the replies.
I like the way yngmar fixed the problem but I am a bit afraid that the fitting - as rotten as it looks -  falls apart when I put any real pressure on it (which is almost unavoidable when taking off the pipe to the outflow valve) so I rather want to be prepared for this case.
The tank has an inspection hole in the front so it might be a bit easier to get to the inside of the fitting. Apart from the problem to get to the backing nut of the fitting the seal looks a bit "non-standard" to me.

Anyone out there who has actually gone thru is and changed the fitting ??

While at it I also want to change the head seacocks and thru-hulls. The trudesign plastic ones seem to be a good solution, I was just surprised that they are supposed to be epoxied in, is that what those of you who have them did ?

[Yngmar]

While at it I also want to change the head seacocks and thru-hulls. The trudesign plastic ones seem to be a good solution, I was just surprised that they are supposed to be epoxied in, is that what those of you who have them did ?

I've fitted Tru-Design everywhere (except saildrive intake) in 2015 and when I did it, there was nothing in the instructions about needing to epoxy them in. I made HDPE sheet backing plates and fitted as per instructions with adhesive sealant (using the option load-bearing collars). One thing I can add now is that when using angled hosetails, best use adhesive sealant for them too. Mine leaked a tiny bit when using PTFE tape, as the hoses flex slightly and the hosetail rotates a bit. Had to undo the hosetails and apply some goop to cure this.

Thread with photo: http://www.bavariayacht.info/forum/index.php?topic=541.0
And shopping list: http://www.bavariayacht.info/forum/index.php?topic=1204.25

[tomgaeb]

Here's the extract from the fitting instructions on Trudesign website:
Sealant:
Tru Design suggest using Epoxy-West system or similar two pot epoxy that mixes to a paste and not a liquid type resin, as this will run and will create an undesirable finish. Tip ? adding powder to the West System will help minimize ?running? of the epoxy.
Fitting:
Smear the epoxy paste on the underside of the skin fitting flange and a small way up the threaded diameter but no further than the thickness of the hull. It is important not to have any epoxy on the exposed thread area.