Tach cable problem on 250

[Pat Fischer <pfischer@rmi.net>]

While driving my TR to work a couple weeks ago, the tach was operating 
normally - then it wasn't. I saw a brief bob of the needle, and then it 
dropped to 0.  We have a new cable we're trying to install.

We hooked the new cable to the tach. If we try to turn the distributor 
end of the cable by hand, it won't turn. Should it be this hard?  We're 
thinking not. (The cable turned easily out of the car.)  Is something 
wrong?  Ideas for fixing?

Many thanks in advance.
Pat Fischer/Roger Elliott