Ok, I learned something today. It's hard to believe :-) When the head temp
sender falls out of the head due to lack of threads as in my case, you can't
just put it back in the hole while on the road. When this happens, the
engine will not run, period. When it's just loose, it'll run, but not very
well. 

I had to take the bus to the repair shop to get the unit put into another
hole. How to get it there? To get it home from the brewpub, I stuffed a
towel in there to hold it in place. I didn't have far to go. I figured the
towel wouldn't get hot enough to combust in the short distance. I had
farther to go to get it to the shop.

I learned the sender is just a thermistor. It's basically a resistor that
changes resistance as the temp changes. 

Everyone has one of the Muir static timing lights in their tool kit right??
If not you should. My static light is just a lightbulb in a socket with clip
leads on each wire. 

What else is a resistor? Right, a light bulb. All I had to do was to clip
the wires in place of the head temp sender and it ran like a champ. Next
time this happens, that's what I'll do and it'll get me home fine. I won't
have to drive 1000 miles at less than 55 mph! This is just a temporary fix
to get it to the repair shop, but I suspect it'll get me home better than a
towel next time.

If your engine is sputtering and you suspect a bad or loose sending unit,
just unhook it and put your static light in it's place. If it doesn't get
better, provided your bulb is good, it probably isn't the sending unit.
Jim Kirk
captain@iquest.net