Headstock Lock Seized

[DrTomServo]

Hello Everyone. I just purchased my '94 Mark V off Craigslist for a steal of a price. It's old, needed some oil/lube and a good dusting off. After further investigation, the headstock lock is seized; and not any way that I was able to look up on this forum. The wedge on the outside (side opposite the power button) is stuck in the lock position. The wedge on the inside has now extended double and the lip that should stop it has all cracked off.

This makes replacing the headstock lock based on the write from the service adviser impossible. I cant get the headstock off.

My plan is to use a hacksaw to cut about 1/2" off the threaded rod in the middle. This will allow me to unscrew the inside wedge out and tap the outside wedge out with a socket.

Anyone know of a better way or see a problem with this?

When installing the new headstock lock assembly, should I use graphite lube around the wedges?

Thanks for the help.

[wa2crk]

Hi Tom and welcome to the "Farm"
How did you ascertain that the stop lip has been broken? Have you been able to open the headstock or did some of the parts fall out.
As a general rule when the wedge locks are that far gone the only to get the parts out of the headstock is to cut the threaded rod. One word of caution, the operator's side of the rod has left handed threads. You will probably have to remove the headstock lock handle by driving out the roll pin and remove the handle by turning the handle to the right to unscrew it. Then cutting the rod in the middle inside of the headstock the pieces can be removed by pushing them into the headstock. It is necessary to remove the motor and motor pan to do this.
And yes graphite can be used on the threads after reassembly.
By the way, 94 is not old it is just maturing at this point.
We also like pictures here so if you can post a bunch.
If you are willing please post your location on your profile. There just might be a member close by to give some personal assistance.
Bill V

[DrTomServo]

Thanks Bill,

I took the motor, belt cover and back cover off to determine that the headstock lock needed to be replaced. Thanks for the help. The situation is about how I expected. Just wanted to double check there wasn't an easier way.

I've updated my location to Austin, TX but not sure it's showing up.

Thanks again.

[DrTomServo]

Ah, put it in the wrong spot. There are two for some reason.

[JPG]

If the rear wedge is seized, have you tried penetrating oil(kerosene works, but there are other 'penetrants). Then after time to 'soak in' some gentle,increasingly forceful impact force to the wedge(not the screw) inward until it moves.

Realize the wedges are soft and the internal threads are easily striped.

THEN you will have to use the hack saw.

Is the screw moving in/out of both wedges as the shaft is turned?