3.0 litre engine. Had a garage mechanic replace water pump. 4 weeks
later it continues to leak, but only when the engine in cold. I have
isolated the leak to the timing belt housing that covers the water
pump, but have not attempted to get behind that cover.
Assuming the mechanic did replace the pump. He worked on it a second
time, but only so far as re-tightening the bolts. What is the most
likely cause of the continued leak? Is it the O ring that connects to
the engine? Is it a bad gasket connecting the two halves? Is it a tube
connecting to the pump?
It is odd that it will only leak when the engine is cold, or when I
apply pressure to the upper radiator hose. When the engine is cold, it
will drip, drip drip when I add coolant. Loses between a quart and
half gallon after each trip.