Stock rocker shaft oil hole orientation

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oliver

oliver

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Just noticed one 2 different sets of rocker shafts, the oiling holes and orientation notches are completely different. Whats up with this? Seems like the rocker shaft on the right is drilled completely wrong as the wear pattern is completely offset from the oil hole. Could the shaft on the right be original mechanical cam 273 shafts? They only have one set of small oiling holes.

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Every ***'y diagram I've seen shows the small oil holes pointing "down" away from the bolt hole centerlines. Don't worry about the notched ends, as many were notched incorrectly. (and I'd say the shaft on the right in your photo was made incorrectly, but it may still be useable)
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69_340_GTS said:
Every ***'y diagram I've seen shows the small oil holes pointing "down" away from the bolt hole centerlines. Don't worry about the notched ends, as many were notched incorrectly. (and I'd say the shaft on the left in your photo was made incorrectly, but it may still be useable)
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hmm, do you mean the shaft on the right is wrong, because look how far off they are clocked compared to the drawings. seems like the one on the left is correct.
 
oliver said:
hmm, do you mean the shaft on the right is wrong, because look how far off they are clocked compared to the drawings. seems like the one on the left is correct.
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Yes on the right. (I corrected my post now). Looks like they are about 45° offset to the bolt holes. I think you can use them, just orient the holes per the Chrysler diagram. As long as they basically point "down" they should work.
 
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I have a bunch of SB shafts and I think the old hyd ones had the small holes and the later LA they changed it to a bigger hole and changed the location a little. The mech 273 had banana grooves and 2 sets of holes
 
Left and down with the notch. later ones was left and facing the intake side of the head.

So the driver side notch is at the front of the motor and the passanger side notch is at the rear.
 
Jadaharabi said:
Left and down with the notch. later ones was left and facing the intake side of the head.

So the driver side notch is at the front of the motor and the passanger side notch is at the rear.
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Only if they are notched correctly. I have seen many with bad notches. You have to look at where the oil holes are pointing.
 
The wear patterns say what they are from. The left one is for the hydraulic lifters and stamped rockers... the narrow area in the middle of each rocker wear pattern, where there is no wear, is from the formed groove along the bottom of the stamped rocker. The large hole looks normal from what little I have seen of those shafts.

OP, you have it correct about the right hand shaft. The wear pattern on the right looks to be for the 273 adjustable rockers for solid lifter cams; there is no 'no-wear' area in the middle of each wear pattern. That hole on the side would be for the squirt hole to the pushrod & adjuster area. Mine have a 2nd hole pointing downward plus banana grooves. But perhaps some of those solid lifter shafts had the lower hole omitted.
 
what happens if you turn that right shaft around difference in offset would be much less the way it looks
do orientate the way the diagram shows holes on the intake manifold side
 
Wyrmrider said:
what happens if you turn that right shaft around difference in offset would be much less the way it looks
do orientate the way the diagram shows holes on the intake manifold side
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Yeah. I think we figured that the shafts on the right are for mechanical cams and the oil hole points towards the intake.
 
Remember the Road Runner method. The shafts have slots in the end. The passenger side shaft, the slot in the end goes down and to the rear. Right Rear. Road Runner. Driver's side goes slot down to the front. This puts the holes......regardless of size in the correct orientation. The holes always point to down and to the outside of the center line of the engine.
 
RustyRatRod said:
Remember the Road Runner method. The shafts have slots in the end. The passenger side shaft, the slot in the end goes down and to the rear. Right Rear. Road Runner. Driver's side goes slot down to the front. This puts the holes......regardless of size in the correct orientation. The holes always point to down and to the outside of the center line of the engine.
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I knew that. My question mainly was about the oil hole orientation vs the slot position. Basically we figured out that the shafts on the right are for solid lifters, that's why the oil holes are biased towards the intake vs towards the exhaust.
 
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oliver said:
I knew that. My question mainly was about the oil hole orientation vs the slot position. Basically we figured out that the shafts on the left are for solid lifters, that's why the oil holes are biased towards the intake vs towards the exhaust.
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Really? First time I've heard this. Where'd you find this information?
 
oliver said:
I knew that. My question mainly was about the oil hole orientation vs the slot position. Basically we figured out that the shafts on the left are for solid lifters, that's why the oil holes are biased towards the intake vs towards the exhaust.
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That's right, your two different shafts one for hydraulic one for solid adjustable rockers
 
RustyRatRod said:
Really? First time I've heard this. Where'd you find this information?
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They are what are usually thought of as the '2nd' set of holes, to oil the pushrod cup through the matching hole in the pushrod end of the rocker. I've not seen one like the OP posted on the right of his pix, where the shaft was lacking a '1st' set of holes pointing downward in the usual direction.

My 273 adjustable shafts have both sets of holes. (Plus banana groove). I can't explain all the varieties of these shafts.... maybe some for 2BBL and some for 4 BBL???
 
nm9stheham said:
They are what are usually thought of as the '2nd' set of holes, to oil the pushrod cup through the matching hole in the pushrod end of the rocker. I've not seen one like the OP posted on the right of his pix, where the shaft was lacking a '1st' set of holes pointing downward in the usual direction.

My 273 adjustable shafts have both sets of holes. (Plus banana groove). I can't explain all the varieties of these shafts.... maybe some for 2BBL and some for 4 BBL???
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Plus all the W2 and aftermarket variants. Makes it confusious.
 
well, I guess that answers my old question on what the differences were between mech and hydro rocker arms.
 
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