Frustrated - Coolant Leak at Drain Tap

[Lin]

As many of you know, I just about have my restoration complete. However, I encountered a problem this week that I have yet to solve. The water drain tap on the LH side of the block (not the heater valve) begins to leak when I get to about 165 degrees. Slow drip at first and then more rapid. Coolant all over the garage floor!

I was using the original drain tap, so I ordered a new one to try. It leaks also!!!!

Have others of you encountered this? What suggestions do you have for fixing this. I can take it out and give the end a whack with a punch to try to "set" it in the valve. It is not easy to get to as it is behind the exhaust headers, heat shield and carbs. I did find that I can approach it from the front of the car.

I need help!!!

Lin
1960 BT7 in restoration
1959 Bugeye

 

[roscoe]

Hopefully you are absolutely sure it is the tap that is leaking and not the threads in the block. A small crack might open up just a bit when things get warm. If you have a plug you can put in in place of the tap, that would eliminate a small crack (or confirm it in the worst case). Alternatively, you could use a soft tipped air nozzle to see if the tap is leaking. Just remove it and plop it into some hot water, pull it out and pressurize it with some some shop air to see if it leaks. All that being said, if you can disassemble the valve and put some fine valve grinding compound on the core and then lapp it to make a good seat, clean off the compound and try again. Hope I haven't stated the obvious to you.

 

[Lin]

Thanks, John!
I gave the original drain tap a little help with a hammer and punch and reinstalled. It seems to be working fine!

Lin
1960 BT7 in restoration
1959 Bugeye