Leaking BSP Fittings-any plummers out there?

R

robbieg

Well-Known Member
Joined
25 Sep 2003
Messages
934
Location
Brixham/Midlands
Visit site
I've just put in a hot water system which is working well apart from one slight niggle. The take offs for the hot water outlet & inlet on the engine are BSP fittings. For various reasons I have a 3/8th fitting tapped in to the engine which is connected to a reducer & then to a 3/4 hosetail-that means 3 threaded fittings before we get to the hose going to the calorifier.

Despite liberal use of ptf tape & much tightening with spanners the reducer fittings leak-not much but enought to be anoying.

It only leaks when the engines running & warm-heat and expansion I assume. The fittings don't have to come apart again once together-any ideas for curing the leak once & for all. I've been wondering about using gasket goo or similar on the fittings-or could I solder them.

Any ideas gratefully recieved.
 
Hello,

Leaking pipes are no fun. Believe it or not, I used flax and some paste (looks like linseed oil and maybe putty) to put together my through-hulls and valves with respetive fittings. Some plumbers use flax and linseed oil. I also have used this combination in plumbing things at home. This was the traditional way to to threaded fittings (so I was told by a plumber) and I'm not the only one to use it here since it is sold in a lot hardware places. The flax expands and the threaded joint doesn't have to be screwed up real tight.

We also have some stuff that looks like dental floss which I have also used, mostly for the bottom drain for the bilge. We pull the boat up every fall so the plug is always going in and out and I only wanted a temporary solution.

Jonathan
 
You could use Boss Green from your local DIY or plumbing shop. If you use PTFE tape the trick is to use a lot! If you can still see the thread bumps you have not wound on enough. I just had to take my home shower mixer apart and redo all the 1/2 inch connections to it as they all leaked after the first fitting due to not enough tape being wound on.
 
I use Fernox LS(X), a silicon sealant. It's terriffic stuff. I even use it on my skin fittings. Once you break the seal, it'll come off by rubbing with your fingers but until then it's damned good!
 
I know this sounds daft, but have you checked to see if the compression fitting nuts are cracked and not pulling the pipes on to their seats properly. I had this with some gas fittings once and it wasn't immediately obvious until I looked carefully!
 
All the threading tape, PTFE etc. etc. is basically useless, so is Boss Green. the only product to use on threaded fittings, is still the old fashon way of hemp & boss white. or alternativly Jet Blue.
Do not overtighten as you "strech" the fittings, & I suspect that is what you have done now, If you can, replace all the threaded fittings with new & start again, go to some one like BSS or Plumb Center in your local trading estate they should be able to help.

As the circuit you are fixing is, I assume, the Heating Primary to your cylinder/calorifier the fittings are presumable steel?
is this correct?

If so, probably worth changing to brass which is softer & makes a better joint. The only problem maybe later on (many years) with dizincification, what ever you use there will be some corrosion as you have dissimilar metals.

good luck

poter.
 
Note that BSP fittings come in parallel and tapered threads.
If you mix the two then it is a problem.
You will need lots of 'gunk' to match the mix...
Worth checking ???
 
At the pipe junctions use compression fittings and make sure you use copper olives. The brass ones are always a problem in my experience.
 
I thought it was only the male threads that were tapered and that for the joints in question it is tapered males screwing into parallel threaded females with tape or jointing compound.
 
[ QUOTE ]
Boss white isn't allowed for potable water is it?

[/ QUOTE ] I don't know if thats right or not, but the question is about the engine cooling water circuit.
 
You must log in or register to reply here.

Share this page

Top