SHOWER DRAIN OUTLET WOES ; LM 32

[alisdairjohnston]

Good morning fellow-forumites,

Can anyone please advise on possible solutions to this minor (but annoying) issue? 

Nordlys, an LM 32, has a built in shower tray and pump.  The pump works (well, as far as I can see), but the tray doesn't drain.
As some will know, the tube from the tray outlet to the pump runs within the interior moulding, so it's impossible to see if there is an obstruction in the pipe, or to see if water is moving within it.

So far, I have tried rodding the outlet with a screwdriver to dislodge any detritus.

Are there any more obvious things I should be doing?

Thanks in advance.
Alisdair

[Sula]

Hi Alisdair,

I know nothing of the LM32's plumbing, but we do have extensive experience of unblocking the drains in our house (the plumbing is poorly installed, has accumulated a collection of small toys, nail files, etc. in it from previous residents, and we have hard water which produces a lot of scum).

Likely the easiest solution is to buy a bottle of drain unblocker, available for a couple of quid or so from any large supermarket. This is a liquid or gel you pour down the shower drain, and then leave for a bit while it dissolves the hair, soap and scum that is probably what is blocking the pipe. You then flush it through with plenty of (preferably hot) water. Note this unblocker is fairly strong stuff containing caustic soda etc., so you need to use rubber gloves, read the instructions/warnings, ensure it doesn't get in the pump or on any gold fittings you may have in your shower , and arrange a spill-proof means of collecting all the liquid and detritus that comes out of the downstream end of the pipe. (You don't want it ending up in the bilge or a locker.)  Amazingly this stuff is said to be safe for septic tanks (such as we have) and public drains, so suitably diluted by the flushing water it would be easy enough to dispose of.

Should that fail, we have also used a variety of proprietary mechanical pipe unblockers from hardware shops and eBay, which have a flexible (but not too flexible) thin rod which can be pushed round bends, with a small brush or scraper on the end to dislodge a blockage. The best, or at least certainly the most entertaining, one had small crank handle on the 'operator' end, which allowed the user to rotate the rod, and a selection of small brushes, prodders and other fittings to go on the twirling 'business' end of the rod.  

Good luck with your endeavours.

John

[Brian & Glenda]

My LM32 shower has its pump sitting at the lowest point of the shower tray, and within the shower tray, and its hose runs from there under the head floor as you say, to a point adjacent the hull on the aft side of the toilet where it reappears, and it goes from there up the inside of the hull behind the sliding sink where it goes through an anti-siphon loop, and then back down discharges through a through hull just above the waterline behind the toilet.

[alisdairjohnston]

Thanks Brian.

That sounds a more sensible solution to my non-technical brain, I'm afraid the layout on our boat is totally different- the pump being well forward under the fore cabin bunk, and discharging above the waterline at the bow. Odd that there should be so much difference!

[Brian & Glenda]

Very odd... When I bought my 1983 LM32 in 2014; the hole 'above the waterline at the bow' of my boat served as the vent for the holding tank! I thought that to be very odd as it was in the bow wave when underway! I relocated the vent to a point just below the rub strake at the aft end of the anchor locker.