On Sun, 12 Nov 2017 23:46:30 +0000, Roger Hayter wrote:

Cherie Plum wrote:

On 11/11/2017 00:54, Roger Hayter wrote:

Do you do solder joints?

No. No yet ....

Anyhow popped back here to let you all know of my success today, a
great sense of achievement when I had finished.
It was a cross thread.I took the arm and ballcock out of the cistern
which was difficult as the outer holding/spacer nut squeaked and stuck
trying to get it off. I cleaned everything and tried a random nut and
it went on the thread fine, I then tried the tap connector nut on a
spare screw thing and it went on so that puzzled me. Then I put the
originals together and I could see it was straight and fairly easy to
screw on so I wondered if undoing the holding/spacer nut had cut a new
thread. Anyway putting it all back it worked! no leak!

Thanks all for the advice.

That's a very satisfactory outcome. Agree, taking the nut back over the
thread is a standard way of cleaning up minor damage to a thread, say
after cutting a bolt.. Very good job, and didn't cost too much! As a
lesson, it shows the importance of being very careful not to cross
thread especially plastic threads with a metal nut. Unless of course it
was the person who originally put the nut on who cross threaded it,
which is quite possible.

Rather coincidentally, I've been having cistern problems the past couple
of days. It's a conventional siphon flush cistern but low level (bottom
of the cistern mounted about a foot or so above the toilet bowl rim). It
had originally used a conventional ball cock filling system until I
"upgraded" it (along with the downstairs toilet and the attic header
tank) with "Fluidmaster"(tm) valves about 7 or 8 years ago. Actually, the
one in the attic, afaicr, was a different brand but the same servo
controlled valve system with a float riding up and down the stem pipe
which muffles the sound of the discharge into the tank.

When I first fitted these filling valves to the downstairs shower room
toilet and the half landing toilet. I was quite pleased with the initial
result. Mind you, you have to carefully align them up to avoid the float
fouling the siphon bell or cistern side - there's very little wriggle
room.

All that aside, after maybe some 6 to 12 months of service, first one,
then the other suddenly took to ****ing water out of (what I assume to
be) the air breaker vents, spraying jets between the top of the cisterns
and their lids resulting in minor flooding. My solution was the rather
pragmatic use of used aluminium pie cases as deflectors to divert the
spray away from the gaps between the lids and their cisterns - a sort of
"tinfoil hat" if you will.

About two years after the initial fit, we had the downstairs shower room
completely revamped which resulted in the existing loo being scrapped.
Luckily, I'd had the presence of mind to recover the Fluidmaster valve
and store it back in its original packaging, instruction sheet and all,
which I'd had the presence of mind to retain (I only kept one lot of
packaging but one was enough). At the time, my family thought I was a
little mad to be saving the valve from being scrapped but what do
families know, eh?

Anyway, the one remaining Fluidmaster (with its tinfoil hat to make up
for its major design flaw) performed pretty well flawlessly until almost
a week ago when I found myself having to replace the flush handle on
account of the hole on the clamped on rusty iron bar through which the
brass siphon linkage hooked had rusted through becoming a slot, allowing
the siphon linkage to escape. I'd have rotated the rusty cross bar to
save on the expense of parts except for the fact that the only way to
free it off involved a pair of bolt cutters and molegrips to break the
clamp apart. It was sadly beyond redemption so I found myself at the
"Plumb Centre" trade counter blowing the best part of a fiver on a
replacement handle kit. I only mention this on account of the fun that
followed a few days after successfully completing the repair.

The disturbance due to fixing the flush handle mechanism upset my finely
moulded tinfoil hat spray deflector and the 'angle of dangle' of the
fluidmaster which took me a few days to settle down (as I prematurely
thought). I was having difficulty in readjusting to avoid failed refills
and failed shut offs.

Eventually, I gave up on the tinfoil hat and tried wrapping the air
breaker vents with SA tape. This actually seemed to do the trick without
apparent compromise to the valve's operation, leading me to wonder why
such an air break had been deemed necessary in the first place (a
question to which, even now, I'm still not quite sure of the answer[1]).

Anyhow, two or three days later, having got used to the occasional need
to encourage the fluidmaster valve to admit water, I discovered the half
landing toilet floor awash due to the valve sticking on a few minutes
after my missus had flushed it. I could see water escaping from the
overflow joint as well as a copious leak past the flush handle spindle
(added to by the water level overtopping the back of the cistern which
was, for no good reason, cursed by a 15mm reduction of the rim height
over a section of about 4 or 5 cms slap bang in the middle.

My first concern was the massive overflow drainage failure followed by,
not only that but badly sealed joint of same into the cistern and the
woefully inadequate flush handle spindle seal. Only then did I ponder the
fill valve failure which, in normal circumstances wouldn't be considered
a major fail when you have an effective overflow outlet to make the
system completely 'failsafe'.

When I disassembled the overflow pipework to check for blockages, I
noted the use of a single thin polyethylene washer on the external face
with a thick coating of what looked like some jointing compound (Boss
White?) slapped over the plastic retaining nut. The overflow pipe was as
clean as a whistle so I cleaned the gunk off the outlet threads discarded
the polyethylene washer and fitted a rubber washer under the retaining
nut to properly seal the connection.

The problem with the overflow is simply that it can't cope with the
binary operation of a Fluidmaster when it fails to shut off the flow due
to a lack of fall in the 2 foot of overflow pipe which has to pass
through a solid one foot thick brick wall (Victorian built property).
I've no doubt it would have been able to cope with the dribble of a
conventional ball cock valve which tends to fail to entirely shut off
rather fail stuck in full flow.

Anyway, by taking the appropriate care in refitting the plastic overflow
parts and fit an actual sealing washer where it counts, on the inside.
I'd eliminated just one of the annoying leaks that only happen under
'failsafe' conditions. I then had to see what, if anything could be done
about my recently purchased flush handle and its rather ****y spindle
bearing. In short, nothing could be done so I looked to the original
flush handle which I'd kept hold of (the rusted through bar and its
wrecked clamp I'd consigned to the garbage but the actual handle looked
retrievable so considered worth hanging onto - I hate burning my boats).

The 'corrosion' on the spindle was essentially lime scale, presumably it
had been forged out of chrome steel, unlike the attached bar and clamp,
so it took just 5 or 10 minutes to dress it up with a file and some wire
wool. It didn't need to look pretty, just smoothed down enough to push
into the rectangular hole in the plastic siphon operating lever from the
new flush handle kit. The old handle spindle was a much better fit in its
nylon bearing, enough to reduce the copious ****ing down to more of a
weep.

At this point, I could see that the overflow simply couldn't cope with a
stuck on Fluidmaster, however, after scrutinising the instruction leaflet
and the spare valve, I hoped against hope that I'd removed the flow
restrictor when I'd fitted it to compensate for the reduced pressure of a
half landing toilet location compared to the downstairs toilet which I
remembered specifically fitting (or, as it turned out, not removing).
Unfortunately, reducing the flow by refitting the flow restrictor wasn't
an option since it hadn't been removed in the first place.

If needs must, I reckon I can fill in some of the restrictor fluting
with hot melt glue to further reduce the flow rate to a point where the
existing overflow can cope. However, I'm thinking of filling in the low
section at the back of the cistern with some sort of epoxy filler to
raise the over-topping level another half inch or so to increase the
overflow drainage rate. If it works, I'll still have to contend with the
dribble of leakage from the flush handle bearing. I might be able to fix
this with application of a very thick nylon friendly grease. I guess I
should google for the grease resistant properties of nylon (I know the
standard lubricant for nylon bearings is water but, for obvious reasons,
this is not an option).

One of the major issues with Sunday's bout of 'plumbing work' was the
lack of a seperate isolator valve to save me having to run up and down
the stairs between the toilet and the basement stop cock. I've dug out a
brand new, unused half inch valve which proves to be blessed with 15mm
olives (14.98mm ID according to my Workzone electronic caliper) which
matches the 15mm (actually 15.08mm OD according to the same caliper)
pipework feeding the cistern.

I think my very next job is to install this valve before doing any more
'experimental' work on eliminating the flooding hazard of a stuck on
Fluidmaster valve. I'll be able to use it to restrict the flow by way of
an experiment to prove whether such a remedy would render the system
failsafe with the existing overflow setup. The result might see me
fitting an old fashioned ballcock valve which does at least, fail to stop
the flow in a more overflow friendly fashion. Upgrading the overflow to
cope with a Fluidmaster valve failure would require drilling another exit
hole in the wall at a 45 degree angle in order to speed the flow
sufficiently to avoid being overwhelmed by valve failure of the
Fluidmaster kind.

[1] I landed up using the spare Fluidmaster valve which I'd modified by
drilling a passage via the blind small bore plastic hose connector (think
windscreen washer hose nipple) that was present on the blue plastic 'air
breaker' top and sealed the vents with careful application of hot melt
glue as an alternative to my use of SA tape on the original valve.

Initially, I didn't fit the short 5 inches or so of plastic tubing that
I thought might be needed when I turned the water supply back on which
proved to be a mistake since despite the greater throw across almost the
whole width of the cistern, the resulting jet of water was enough to
raise enough spray to soak the toilet seat (cistern lid off) in the
minute it took me to return from the basement stopcock.

That problem was solved swiftly enough using a short length of curved
windscreen wash tubing to divert the flow at an angle against the side of
the cistern and deflect it downwards into the water. That dead ended
plastic hose connector 'ornament' on the blue plastic 'air breaker' had
been a constant source of puzzlement. Having a 'spare' to experiment on
gave me the luxury of drilling the blockage out to verify my suspicion
that it did indeed offer an alternative 'venting' route, allowing me to
block the original vents without fear of upsetting what may or may not
have been a vital part of the valve's operation.

Presumably this 'air breaker' incorporates a one way valve to prevent
spray back. It's rather unfortunate that my experience with two examples
of this valve type have led me to conclude that its design left rather
too much to be desired, ie reliability. However, blocking the vents and
drilling out the pipe connection does offer a reasonably neat work around
to this annoying shortcoming. Presumably, there must have been some
reason why the design included such a venting route, subsequently one has
to assume, to be superceded by the 'spray back' prone vent ports.

The important lesson from this experience is that anyone upgrading from
a conventional 'tried and tested' ball cock float valve to one of these
new fangled servo operated float valves is to make sure that the overflow
can cope with the effects of a shut off failure.

--
Johnny B Good