Technical Rocker shaft cleaning.

[paul in manche]

Gradually putting the engine back together in between other garage related jobs.
I've got the rocker shaft completely dismantled - a certain amount of swearing involved as a couple of the rockers were completely solid on the shaft. I left the whole lot marinating in paraffin for about 36 hours, then it stripped down much more easily. There was a certain amount of debris in the holes, a couple of the smaller ones that feed oil to the rocker fingers were blocked.
What's the best way of getting rid of the rest of the debris / muck inside, assuming that the two outer parts of the shaft don't come off the inner?
My thoughts were one - stick it in the ultrasonic cleaner and hope that it gets rid of most of it, or two drill a hole in the end, clear it all out, tap the hole and put a bolt in to fill the hole back up.
As always any help would be much appreciated.

 

[the hobbler]

Gradually putting the engine back together in between other garage related jobs.
I've got the rocker shaft completely dismantled - a certain amount of swearing involved as a couple of the rockers were completely solid on the shaft. I left the whole lot marinating in paraffin for about 36 hours, then it stripped down much more easily. There was a certain amount of debris in the holes, a couple of the smaller ones that feed oil to the rocker fingers were blocked.
What's the best way of getting rid of the rest of the debris / muck inside, assuming that the two outer parts of the shaft don't come off the inner?
My thoughts were one - stick it in the ultrasonic cleaner and hope that it gets rid of most of it, or two drill a hole in the end, clear it all out, tap the hole and put a bolt in to fill the hole back up.
As always any help would be much appreciated.

Rocker-shafts are usually a bugger to take apart! I have found that nearly ALL the shafts that Ihave stripped have had the towers seized in place (mainly because they don't rotate)---sometimes to the point where a certain amount of (gentle) brute force is required to remove them. I would NOT reccomend that you start drilling holes and then putting bolts into the hole---the ultusonic-cleaner sounds the best bet, and then a good blowing out with an air-line. Whenever I have stripped a rocker-shaft to clean, I have carefully cleaned the inside of the towers with a roll-up of fine emery-cloth AND the saft (with the same) to a point that the towers are gentle/firm push back onto the shaft

 

[giardini]

You're luckier than I was to have caught it in time.
Shortly after acquiring my Giardiniera 20-odd yrs ago, I had a major "episode" with a rocker seizing onto the shaft in the open position,
and a meeting of a valve and piston crown with destruction of both, plus terminal damage to the combustion chamber.
On inspection, I found that the space inside the shaft was solid with crud compacted to the consistency of coal. I imagine the engine had
been run on non-detergent oil for some years, then switched to detergent, liberating years of deposits that collected inside the shaft.
The only certain way of getting it all out was to drill out the end plugs of the shaft and ream it all out of there. I turned a pair of new aluminium
plugs on the lathe, pressed them in with a good interference fit, and it's been fine since.
I would not have trusted another cleaning method, never knowing if a leftover piece of crud might block one of the rockers' lube hole again.
You also can't tap the shaft end for a blanking bolt, as it's all surface-hardened. I hope this helps.

 

[paul in manche]

Spent ages yesterday looking for the rocker shaft, then gave up and found the other set of rockers (one of the benefits of making one engine out of two!). These were all moving ok, so I stripped them right down, the central shaft was pretty clean - no holes blocked, so the whole lot got 3 goes round in the ultrasonic cleaner and came up very clean. Soon as I'd reassembled the shaft I remembered where the first shaft was - I've got to that sort of age!!
Off out into the garage to sort out the valve clearances now.