4spdragtop
Well-Known Member
Where does pushrod oiling come from? Only in banana groove shafts?
Adjustable rockers a few questions.
- Thread starter 4spdragtop
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From the same hole.
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The pushrod oiling comes from the oil that is around the shaft underneath the rocker arm coming out of that little hole on the adjuster side it runs around the adjuster there's kind of a cup made into the rocker arm there and that runs down on to the pushrod.
I highly recommend plugging that outside machine hole on the adjuster side of the rocker arm. That is just an escape point for the oil that is trying to work its way down to the pushrod. That hole was put there so they could drill into the center of the rocker arm to get oil from the shaft to oil the pushrod.
4spdragtop
Well-Known Member
Thanks guys, great info. I'll do the mods when the time comes. Thanks!
The greatest load on those rocker arms is on the bottom where you need the banana grooves. Every bit of the spring pressure that is holding against that valve is pushing against the bottom of that rocker arm shaft.
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Let me rephrase that.
The greatest load against the rocker arm shafts is at the bottom where the banana grooves are.
The greatest load on the rocker arm is going to be at the rocker arm tip or at the tip of the adjuster. Remember we are multiplying by the rocker arm ratio here. And there is a change of angle in the pushrod at the adjuster.
rustycowll69
Well-Known Member
exactly. The greatest pressure is concentrated on bottom of shaft, just slightly outboard of the attaching holes in the shaft. I can tell you from painful experience that is where they'll gall up from improper lubrication. The dealership mechanic re-installed mine incorrectly and not only ruined the rockers & shafts, but oil pump, bearings, crank, cam & lifters. Get it right or pay the consequences.
Kendog 170
Let the boy go !
I don't know if this helps at all with the oiling hole alignment .
IMHO......You need 2 sets of holes when running adjustables with hydraulic lifters. One hole keeps the pushrod cup oiled and the unloaded part of the shaft, and the other with the banana groove keeps the loaded side of the shaft oiled. I ditched my single hole shafts when I saw evidence of heavy wear exactly where the second hole and the banana groove should be.
4spdragtop
Well-Known Member
Hey Troy, this is for solid lifters and adjustable rockers. I knew something wasnt "right" when I was looking at them. 1 step forward and 3 backwards. 
4spdragtop
Well-Known Member
Thanks, is that hyd or solid?
4spdragtop
Well-Known Member
Ok, so thinking about tapping the holes on rocker arms. If the interference fit is in the rockers, why doesnt the jam nut currently thread all the way onto the adjuster??
Kendog 170
Let the boy go !
Sorry IDK it's just something I saved for rocker position reference.
Daves69
Well-Known Member
FWIW, The rockers in the picture are hydraulics.
rustycowll69
Well-Known Member
in principle, it still applies for solids, too.
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That is a picture of hydraulic rockers. They use 1 oiling hole.
How high do you plan to spin your motor?
4spdragtop
Well-Known Member
Not high, 6k max? 
340. 904. I would like to take it down the track at least once or twice.
340. 904. I would like to take it down the track at least once or twice.
You don't HAVE to have two holes. The pushrods will get oil regardless. The oiling hole you have causes the rocker to ride on a pressurized cushion of oil. That oil makes its way around to the oiling holes in the rocker, regardless of whether an "extra" hole is there, or not. Now, what "I" would do is get the whiz wheel and banana groove the shafts at the oiling holes you have. That will allow oil to get into a much larger surface area. @prorac1 and @Prorac2 will chime in and show you the great job they did on theirs....IF they're payin attention. LOL
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Reading all of this has got me confused about my current configuration. The way I just pulled my rocker shafts and adjustable rockers was the drivers side of the engine has the notch cut out at the firewall and the oiling holes at about the 5:00 position pointing at the exhaust side of the head and banana groves at the bottom of the shaft. The passenger side has the notch towards the front and the oiling holes at about the 7:00 position with the banana groves at the bottom and the oiling holes pointing at the exhaust side of the head. If I turn the shafts around or swap the sides the geometry will never be correct if the notches are supposed to be the opposite way. These shafts and adj rockers were installed on my 70 340 way before it was mine.
4spdragtop
Well-Known Member
On our 67 273 stock adjustable setup we put notch down and to the left for both sides(when leaning over fender). I had purchased another used adjustable set for my 70 340 build. I finally got around to checking them out and this is why I started the thread. I would take off your valve covers and inspect to be sure. Cost you a set of gaskets to be sure.
If they have notches, the notch is down and to the rear on the passenger's side and down and to the front on the driver's side. What will they look like if you do that?
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All the "notched" ones I've seen this is true, down and to the left.
I can't say the same about the shafts with the half round or ground on looking cut outs.
And yes some 273s only had 1 set of holes on the bottom of the adjustable rocker shafts.
The bottom hole is on the valve spring side of the pedestal when mounted.
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Yeah, evidently there was more than a couple of different styles.
If I line up the notches as you explained the oiling holes which i only have one row would be pointing to the pushrod side and not the valve spring side. Aren't the oiling holes supposed to be pointing to the 5 oclock position on drivers side and 6 oclock in passenger side?
Then turn the shaft around.
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