rocker arm question

Onder · Jul 17, 2013

Rocker arm in hand out of head. Little, as in almost no, passage of anything even air. Only
the slightest amount. No indication of dirt or swarf more a case of likely always was this way
due to incorrect alignment of pushrod pin.
So: can I simply press out the pin and examine or is this a sure way to ruin the arm and the pin?

Torontonian · Jul 17, 2013

Dunno , reading this sure is a way to ruin my brain though. The idea of the rocker spindle positioning is to restrict oil. The oil gallery cutout flats in the spindles should face towards the rocker covers ,this in an effort to further restrict. The Commando head is overoiled in general. You must heat the head up to extract or insert the rockers and spindle shafts. Whew !

Onder · Jul 17, 2013

It is out in my hand. All the other ones Ive had give free passage from hole in bore of arm
out to the hole in the pin where the push rod meets. Fully understand the oil situation in
regards too much oil but no oil isnt the idea.
AN and RGM both show this as an available part (although 1971 not for later 850 for some
reason), so seems like a removable item.
Nobody ever gone there?

Torontonian · Jul 17, 2013

Are we talking about the rocker arm hardened ball ends that the cup of the pushrod fits into ? Yes those are drilled to supply oil.

Dances with Shrapnel · Jul 17, 2013

Torontonian said:
Are we talking about the rocker arm hardened ball ends that the cup of the pushrod fits into ?

Try using a small steel or stainless steel wire and solvent to open up the passage or at least get a sense of where the blockage may be. You can drift out the balls but need a proper sized drift and a suitable bit to receive the ball end while supporting the rocker and hitting the drift. It is not too difficult. A good machinist vice might work to support the edges of the rocker. Don't try clamping the rocker.

Again, I would spend a little more time with maybe some safety wire and solvent or a bristle from a wire brush.

Patience can be a virtue.

Onder · Jul 17, 2013

Yes of course they are drilled . But obviously either the passage is blocked by
debris or the passage and the ball end stud werent properly lined up at birth.
So having run a piece of safety wire through the passage from the middle
with no change (and no telltale debris of any kind) and putting 100
pound of air on it with only the slightest amount of air coming out
I conclude misalignment .
I just wanted a bit of advise or hand holding on pressing out the pin.
If anybody has another way to clear the passage, speak up!

Hobot · Jul 17, 2013

May have to high heat it to get passages to swell and crude to soften and may have to use that really strong stuff that removes piston coke with its soaking for days and days till opens up or spend about $100 to replace. I found out the hard way the oil passage runs along the side and is pretty shallow, like finger nail thickness.

Dances with Shrapnel · Jul 17, 2013

A tiny bit of debris will have a field day with 100 psig air pressure. If you have not tried rooting around a bit more with solvent it might be worth the extra effort to see if anything breaks loose. If you are getting some air through there then you will get some oil through there and you really do not need much flow so if you have flow I would go with it as is. I think the drilled hole size had more to do with manufacturing practicalities than it did with oil flow capacity.

I would not add heat if you decide to remove and reinstall the ball. It will drift out just fine with the proper set up.

Onder · Jul 17, 2013

Well Im in agreement as far as the heat goes. Dont think it is solid with baked oil and debris
but I could be wrong. Rodding out with the safety wire is tough as you really cannot get in
there very well. Tried copious amounts of brake parts cleaner sprayed in but no joy.
Ill toss it in acetone overnight.
...but in the hard cold light of dawn (metaphorically, east coast USA is sweltering) Ill
drift it out.

Hobot · Jul 17, 2013

As far as the heat concern it may not help at all but the rockers can run at head temps well over 300'F. It would take a lot more heat than that to turn the oil to carbonized crust so expect metallic dust clog no amount of solvent will touch. I'd try a fluid jet or grease pressure over air pressure for this task. Best wishes on opening the passage.

Onder · Jul 17, 2013

Bah. Had at it just, piece of cake. Supported it in the vise and drifted down just enough to
expose the gallery. Clean and true as was the passage in the ball stud.
Off by 15 degrees or so.
Thanks for the hand holding.
Off to bed to sleep the sleep of the (self) righteous!

rocker arm question

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