Driveshaft roll pin hole size

[teejk]

Originally Posted by Matt G.

No, the worn driveshaft and/or coupler needs replacing. Fixing the cause of the problem is much better than a band-aid that fixes the symptoms.

Worn couplers and driveshafts will go through pins much faster, too, another reason to do it right.

ok...makes sense I guess other than I can't envision why the pin would enlarge the hole on either the shaft or the couplers since it is the softer material (shaft 5/8" solid round stock, couplers appear to be cast iron). Try to drive one of those pins out and see what peens first. But what do I know?

but I did get the call today...20 miles to go pick up the $6 round "corky" gasket from the only CC dealer in the area. an opportunity for somebody to package all the gaskets suggested for a 38 year-old 1250 rear-end rebuild...

needed or not, GOUGE me so I only need to make one trip!

[sawdustdad]

In my case, the previous owner of my 149 put a 1/4 inch bolt through the driveshaft at the engine coupler, and it was loose enough that it has apparently damaged the hole to the point it won't hold the pin. It seemed "pretty" tight when I set the pin, but obviously it wasn't tight enough. I'm hoping changing to a flex disk will solve the problem for me.

[teejk]

Originally Posted by sawdustdad

In my case, the previous owner of my 149 put a 1/4 inch bolt through the driveshaft at the engine coupler, and it was loose enough that it has apparently damaged the hole to the point it won't hold the pin. It seemed "pretty" tight when I set the pin, but obviously it wasn't tight enough. I'm hoping changing to a flex disk will solve the problem for me.

sounds like he bored the holes to get the bolt in (that would be easier than doing it right).

not familiar with the 149 at all...did the flex discs come into play with the QL's?

[Matt G.]

teejk-

The pin is hardened and the couplers, driveshaft, and input shaft are not.

[sawdustdad]

Originally Posted by teejk

not familiar with the 149 at all...did the flex discs come into play with the QL's?

I think that's correct. I ordered a couple flex discs, a drive flange and a coupler from ccspecialties. There is another thread--I think it's the 149 resto-mod (red 149) thread where he did this.

[gillis51]

It's supposed to be a 1/4" x 1 1/2" dowel pin.

[sawdustdad]

1/4 hole worked fine. Posted some pictures of the finished drive shaft in another thread. The spiral pin measured .260 dia.