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[harvo]

Suddenly my 71 TR6 has developed a battery drain.  Sitting overnite the battery drains down.  The alternator seems to put out over 13 volts to charge it when engine is on.  Disconnecting the negative battery cable prevents the drain.  Any ideas on what might be the likely culprit.
Thanks very much,
Harvey
New Haven, CT

[none]

I know you have tried disconnecting the battery, but have you tested the battery for its ability to hold a charge. It may have lost some of that ability which can happen quickly and that may have made it easier for a relatively small draw in the system to drain the battery over night. At any rate it would be a good thing to know the state of your battery for certain.
If the battery is good then the draw would have to be more substantial and possibly a hazzard as in something might be getting hot.
The easiest way to check a system is to split it in half and then split the side with the short and on and on till the problem is found. It is not so easy with the wiring in a TR6 but you can work through the electrical system by disconnecting components and eliminate those not part of the problem and work toward identifying the problem.
I would first disconnect the alternator, and next the relays. Use a meter to check the draw as you go.