|Sump repairs won't last
: MY vehicle is a 2001 Proton Waja 1.6
At a recent service, the automatic transmission fluid (ATF) was replaced and in
the process, the mechanic over-tightened
the drain plug, resulting in a small leak at
that point. Wrapping the drain plug's
threads with plumbers' Teflon tape did not
stop the leak.
Upon closer examination, it was discovered that there was a hairline crack in the
vicinity of the drain plug, and the workshop offered to carry out welding repairs
to the area.
I am not sure if this is a safe method of
repair and would appreciate your comments.
SUMP plugs are simply designed to seal,
either by means of a taper machined
beneath the plug-head, or by use of a copper, fibre of aluminium washer. Either way,
they only require gentle tightening in order
to achieve an effective seal.
Over-tightening, as you have discovered,
only serves to damage this seal and the surrounding area.
Although welding can be carried out as a
means of repairing aluminium components,
this is not preferable, and any repairs are
Compared to other common metals, aluminium has a high coefficient of expansion.
This means that it expands more than other
metals for the same temperature rise.
Any imperfections in the weld would
result in a weld fracture within a short time.
I would therefore recommend a replacement
sump. Perhaps a used one from the breaker's
yard can keep cost down.