The simple solution is often the best one.

[Boomlander]

After reconditioning Jethro's radiator at great expense I refitted it and filled with coolant.
Damn! the drain tap was weeping fluid from the swivel thingy.
Drained down and removed the offending brass B@st@%d, stripped it down, cleaned it, tightened the spring by fitting extra washer, refitted with ptfe tape and fibre washers, refilled the rad and hey presto.......It leaked again!
Drained down again, threw the tap in the scrap bin, fitted spare tap after checking it again with ptfe tape and washers, refilled the rad and would you believe it....It leaked the same as the first one!
Drained down, removed and discarded the tap, ordered new simple drain tap from main supplier.
New drain cock a doodle diddley arrived and turned out to be 1/8" BSP instead of 1/4" BSP!!
Sent drain cock a doodle diddley back for refund and ordered correct size from Ebay.
Fitted brand new drain cock a doodle diddley and refilled.............IT BLOODY WELL LEAKED!!!!!
Drained down for the 5th time, flung the useless item as far as I could and sat twitching in front of the car.
Scavenged a 1/4" BSP blanking plug from my odds and sods drawer that came from God knows where, fitted it with ptfe tape and a copper washer, refilled and...... Not a leak in sight!!
A five minute fix for a job that lasted ninety minutes! Ah well that's the car finished at last.....SHOWTIME!!

[philthehill]

You do not have to throw the brass drain tap away because the swivel thing is leaking.
With the brass tap you can lap the brass swivel thing into the brass tap body with some fine valve paste finished off with some Brasso.
Jobs done and no leaks.
Make sure that the small spring under the sector plate and split pin is serviceable because that is what pulls the swivel thing into the tap body. That spring being steel is known to disintegrate.
Phil

[Boomlander]

Thanks Phil, I did like the look of the swivel drain tap and I may have a go at lapping the taper plug to see if it will cure it when I get some spare time next month.
Meanwhile I think I will make do with the leak free blanking plug and just pop the bottom hose when I need to change the coolant.

[Andy W]

Thanks for posting that Boomlander...it helps to know that sort of thing doesn't just happen to me!

[bmcecosse]

No need for a drain tap anyway - a well fitted plug is much more secure, and just drain when required by pulling the bottom hose off....

[Boomlander]

Thanks for posting that Boomlander...it helps to know that sort of thing doesn't just happen to me!

No worries Andy, believe me I could write a book about all the "little jobs" on Jethro that have turned into absolute bloody nightmares - never having much time to spend on the car doesn't help but just wait till I retire!