On the TR-3 through the TR-4A, the water drain 'valve' is
indeed a petcock that is open when the handle is pointing
away from the block (90 degrees to the block) and closed
when it is parrallel with the block. I have found on one
or two occasions that the valve in the open position
fails to drain any coolant. This has always turned out
to be due to the area where the valve accesses being
full of years of sediment.
As a means to clear out this sediment, I remove the
radiator cap and with the valve (petcock) on the block open,
I force in compressed air. You don't need high pressure air,
usually 20 to 25 lps/in will do it. If, as I suspect,
that clears up the passageway, then thoroughly flush the
cooling system several times. The idea is to get as much
of the sediment loose and suspended in the coolant
while flushing out the system.
Bill Sohl
|