FE-FC Holden Discussion Forum

For Sale and Wanted => Parts Wanted => Topic started by: my8thholden on September 10, 2021, 08:04:23 AM



Title: rocker shafts
Post by: my8thholden on September 10, 2021, 08:04:23 AM
I read here over a few years that NEW rocker shafts are hard to get if not impossible , has any one here managed to get or knows of where to get , or have had made a pair of new rocker shafts for Holden grey engine ..thanks Vern


Title: Re: rocker shafts
Post by: ardiesse on September 10, 2021, 09:50:46 AM
Vern,

You would be right, I think.

I've sometimes thought about getting some made, but the effort of reverse-engineering . . .

Otherwise, you could go talk to someone like Diamond Hard Chrome at Enfield, or A1 Metal Spraying.  There's not much difference between a rocker shaft and a hydraulic ram.

Rob


Title: Re: rocker shafts
Post by: my8thholden on September 10, 2021, 07:42:49 PM
Rob ,,What is the correct diameter of the rocker shafts ? , is it in a technical book, my shaft measured 20.1298mm OD where the pedestal is , ie unworn , in the manual only reference I can find is in bush replacement where allowing for clearance it would be as near as .7925 which is near enough to the mm reading ..That is an odd size , one would have thought Holden would have used a standard size of hollow tube ...cheers Vern .


Title: Re: rocker shafts
Post by: ardiesse on September 10, 2021, 08:39:05 PM
Vern,

There'll be reasons why GM-H chose 0.7925", but they're not immediately apparent.

The rocker shafts were in fact stamped out of sheet, rolled up like a hollow section pin, welded and then ground to size.  I guess it saved on material, and there was no need to drill the hole in the shaft.

Rob


Title: Re: rocker shafts
Post by: my8thholden on September 11, 2021, 07:17:47 AM
Rob..They say the day is wasted if you don't learn something , I did not and would never have guessed the rocker shafts were rolled from sheet ..I'll seek yours and anyones comments , you would be aware the shafts wear on the underside where the operating action is the most load ,the thought of turning the shaft over 180 deg ..drill new oil holes on under side , reason being ,move the worn section to the top , its by no means a perfect solution ,but a shaft with minimal wear would be an improvement ,would that create too much back lash ? would you block off the oil holes now on top ?  .keep well Vern .
PS ..Thinking about the oil holes ,the holes now on top would have to be blocked off ,cause they would then be in line with the hole in the rocker ,oil would shoot straight out and the under side would starve for oil.