Gib Key Dimensions

[veggie]

Does anyone know the standard gib key dimensions for a 6/1 ?

I bought a new gib key to install when I was diagnosing my flywheel wobble.
The new key has a nice finish and a consistent taper.
I thought this would be the answer to the sorry excuse for a gib key that this one is replacing.

Upon installation, I found that the new key can be tapped in almost all the way until it hits the flywheel.
The when I run the engine, I here the ping...ping....ping of a loose flywheel with every revolution.

Until I know the proper dimensions for a gib key, I don't know if the problem is the key, or a poorly machined key way in the flywheel.

Below are the dimensions of my new gib key and a picture showing how it fits into the flywheel.
If I tap a bit harder with the hammer, I can get the gib to go all the way in.

veggie

[veggie]

Follow up question:

Assuming the gib key is correct, then the keyway of the shaft or flywheel is too deep.
In that case, is it ok to lay a strip of shim metal in the shaft keyway to create the necessary interference?

See picture....

veggie

[vdubnut62]

According to Jack Belk, the  Indians simply don't use a standard size gib key.
Here is a link to his experience, complete with detailed measurements.
http://utterpower.com/fitting_gib_keys.htm
If I did use a piece of shim stock I would sure keep a close eye on it for a while, until I was sure that the key was not going to move.
Ron.

[billswan]

Veggie

Pull the new one and lay the old one side by side if the old one has enough metal just go after it with a file and make it fit! If the old one is a mess I see no reason a proper quality shim laying in the crank key way would not work.

AS vdubnut62 said keep an eye on it for a while until you are sure it is set.

You got to get that flywheel locked solid before you try any balancing! But you knew that.

Billswan

[mike90045]

And what about using "stuff" to help lock the key in?

I see a shaft collar?

Chalk?
Locktite? (how to remove it?)

[Henry W]

I would try to stay away from Loctite if you can. When you have the proper gib key and it is installed properly the flywheel will stay set.

If you need to use Loctite use Loctote 680 retaining compoud. make sure all parts are clean. Acetone works good.

Henry

[quinnf]

So long as the key is tight and you can get a puller between the head and the hub to remove it later, I'd leave it alone.  The more contact area you have between the key and the crankshaft and flywheel keyways, the more securely your flywheel is held.  The usual problem is with keys that only penetrate about an inch or so into the flywheel.

That said, brass shims would work fine.

Quinn

[Apogee]

You could always just lay a bead of weld down the back of the new key and then grind or file it flat for a perfect fit.

That's what I'd do....

Steve

[listeroil]

I have had a few genuine old lister engines with a shim inserted under the gib key. The main thing to watch out for when fitting gib keys is to make sure that they are not fitted to close to the flywheel. No closer than 1/2 inch for the tang or you wont be able to get the key out again. A shim under the key will be fine that what lister engineers used to do.
Mick

[veggie]

I cut a 4" strip of shim stock the same width as the key way and set it into place. Then I hammered the gib into place.
The key came to a halt with the head about 1" from the flywheel hub.
Perfect spacing for my 3/4 thick gib key puller to grab onto.
The wobble in the flywheel is gone and the wheel seems to be secure.
I will keep an eye on it for a while.

cheers,
veggie

[potter]

On two of my original Listers when I took the flyweels off I found on both hacksaw blade had been used as a shim.