Speedo cable HELP

[Francis F.]

just connected the cable for the first time since resto.
speedometer bouncing 20mph-to-60mph ,then finaly spun the red needle off.
It was a bear to connect up to the powerglide transmission,has anyone had the same problem.
Can a member offer a solution ?car is a "66" coupe/P G/small block,late production,and has been under restoration for a long-long time and going thru a shake down phase.
Francis

[John H.]

Re: Speedo cable HELP

just connected the cable for the first time since resto.
speedometer bouncing 20mph-to-60mph ,then finaly spun the red needle off.
It was a bear to connect up to the powerglide transmission,has anyone had the same problem.
Can a member offer a solution ?car is a "66" coupe/P G/small block,late production,and has been under restoration for a long-long time and going thru a shake down phase.
Francis

Francis -

Usually, that symptom (huge excursions followed by loss of the needle) means the speed cup is physically interfering with the magnets on the first worm, but I'll defer to anyone who knows those internals better than I do.

[Francis F.]

Re: Speedo cable HELP

thanks for the reply's but I may have solved it.I installed a 90*cable adaptor ,used for TACH's and speedo's
it appeares the cable had to be bent in a short radius where it enters the P.G.transmission,(very tight quarters)
no more cable noise,will have to wait to see how it works when needle is back on speedo.
Has anyone else had this problem????let me know
Francis