452
Cleaning out the
drain tube A brief note on an occasional maintenance item which
probably should be available only after the 9pm watershed! Here Victor Smith describes
how to find this item and clean it out. (Aug 12)
Recently I found my V8 with a pool of water in the driver's legwell after
a night out in the elements during the MGLive! weekend. Whilst mopping out I recalled
the late Geoff Allen, our former V8 Historian who worked at the MG Plant for 27
years, telling me about the little known part which drains the fresh air vent
chamber below the small chrome grille immediately in front of the windscreen.
It is AHC321 - Tube-drain and dust valve, which is the polite way of referring
to the rubber tube which was there to act as a drain for the fresh air vent chamber.
Geoff referred to it as "Ted's Knob" as that was the name of the part
on the production line where a fellow with a reputation with ladies was very able
at fitting the part! Well over the years two things happen to Ted's Knob
- first it hardens as the
rubber ages and second the dust, mud and leaves which find their way into the
fresh air chamber accumulate at the bottom and with the water that gets in there
washes down into the rubber drain tube. When all is working well the sludge passes
through but with age there can easily be a blockage. In fact the photo alongside
shows a plug of silt and small stone chips in the hardened slit which had blocked
the drain.
The caution before you start attempting to clean out the rubber
drain is be very careful not to cause the rubber tube to
detach from the upper mounting point as it is a real devil
to put back or fit a replacement. Removing the sludge
needs a long rigid wire inserted from the top through the
grille down through a small circular opening on the base of
the fresh air chamber. A wire coat hanger carefully straightened
can be used. Gradually work your way down through the accumulated
gunge until the lower end goes through the tip of the rubber
drain. You then need to apply a
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Drain tube blocked with a plug of silt and stone chips
careful
reaming action. Then with the car on ramps, get underneath and careful squeezing
of the hardened rubber slit and prolonged excavation with a screwdriver, you will
see an extraordinary variety of material fall by your hands! So it is wise to
wear plastic goggles. The part is shown on page 108-N15 of the MGB Parts
Manual AKM0039 February 1977 First Edition See an illustrated note. More |