No oil thru rocker shafts

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Thanks for the help. A couple of good links to read there. I have a better understanding of it now. I think I will start by replacing the stud with a bolt and see if it helps, if it does then I will try opening the hole in the bottom of the rocker shaft. I have some good info and ideas to try now. Hopefully I will have time to work on it this weekend. I will update my progress and the solution after I work on it. Thanks again.
 
ANd just one more thought to add: with the head stud, the stud being in the middle of the of head hole is necessary.The dowels on the block locate the head, and if those are left out, and just the head studs are used for location, then the head may be be positioned downward. Then the head stud in that particular hole would be right up against the oil hole from the block and could seriously block the oil.

BTW the recess in the pedestal is right at .400" diameter. If you open up the shaft hole to that size, you will have to make sure you visually align the holes; these stock rocker shafts have some play on the shaft bolts.

Marcohotrod said:
the restriction/area around the 1/2" stud and .540 head passage is .033 square inches, same as the restriction/area around the 5/16" shaft bolt and 3/8" stock hole into shaft. when we use the .450" head bolt the restriction/area is .070 square inches, so I grind the oil hole into the shaft on the lower half to line up with the passage in the pedestal.
Click to expand...
I see you computations and they make some sense. Per that the stock restriction at the rocker shaft is about the same as the head stud in the head hole. So, by opening up the rocker shaft hole to a larger size, it is putting a similar sized restriction at the stud-in-head-hole rather than the rocker shaft. That makes good sense.
 
Hello all... I'm having an issue with a 360 I am doing for a buddy. I decided to prime the engine with the valve covers off to check for oil at the rockers. I have Crane cast rockers on Comp shafts (kind of a mix-match, but they fit good). The problem is, at 60PSI the oil is coming out of the shaft at the stands like a waterfall. Very little seems to be making it to the rocker bleed holes or between the rockers. Have any of you guys come across this??? The shafts are not grooved, but the holes are counter sunk. Thanks, Gene.

P.S. I know this is an older thread but seemed like a good place to ask.
 
Alphabet Soup said:
Hello all... I'm having an issue with a 360 I am doing for a buddy. I decided to prime the engine with the valve covers off to check for oil at the rockers. I have Crane cast rockers on Comp shafts (kind of a mix-match, but they fit good). The problem is, at 60PSI the oil is coming out of the shaft at the stands like a waterfall. Very little seems to be making it to the rocker bleed holes or between the rockers. Have any of you guys come across this??? The shafts are not grooved, but the holes are counter sunk. Thanks, Gene.

P.S. I know this is an older thread but seemed like a good place to ask.
Click to expand...
The shafts install only one correct way. There are slots in one end of each shaft. Passenger's side shaft installs with the slot to the rear and down, driver's side shaft installs with the slot to the front and down. Sometimes, there are no slots. In that even, the small oiling holes in the shaft point down and toward the valve springs.
 
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Alphabet Soup said:
Hello all... I'm having an issue with a 360 I am doing for a buddy. I decided to prime the engine with the valve covers off to check for oil at the rockers. I have Crane cast rockers on Comp shafts (kind of a mix-match, but they fit good). The problem is, at 60PSI the oil is coming out of the shaft at the stands like a waterfall. Very little seems to be making it to the rocker bleed holes or between the rockers. Have any of you guys come across this??? The shafts are not grooved, but the holes are counter sunk. Thanks, Gene.

P.S. I know this is an older thread but seemed like a good place to ask.
Click to expand...
Orient the shafts correctly and maybe put a little, like a little.. sealer on each stand before install. It's not common.. but it isn't unheard of either.
 
Thanks, I'm in the know about the shaft holes. This is only the second small block Mopar build for me, but I have built a couple dozen 383 thru 440's. I don't think I have to worry too much about left or right as the holes in these shafts are straight down. I'll have to take the shafts off to get a picture. I am considering putting some groves in them. But there seems to be so much oil out of the stands I'm not sure it would be much help. Gene.

P.S. writing this than re-reading it just gave me an idea to put the rockers on stock shafts and see what happens. I'll report back.
 
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Update, I did try a stock shaft. Things didn't change. I used a die grinder with a very small stone and made some groves in the Comp shaft.
Plenty of oil out between the rockers now and leakage at the stands has slowed down to a seep. Still not seeing much out of the weep
holes in the rocker. But things are looking up. I am including a picture of the Comp shaft, before groves. Thanks for all the help! Gene.

Resized_20250920_174718.jpeg
 
Are these the rockers in question?

If so, they look like 273 rockers, which are different than the cranes I have used.
It’s not much of a pic to go by, but I’m basing it off what appear to be friction lock adjuster screws.

IMG_3979.png
 
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The Cranes have a pretty good size relief cut for the lock nut style adjuster.
The Crane rocker also has a groove cut around the ID to aid with oiling.
IMG_3981.png


IMG_3986.jpeg
 
This is the box the rockers were in when I bought them. Along with the box flap you see. And the push rods you can see.
I assumed they were Crane. The half nuts were included. Gene.

Resized_20250923_181210.jpeg


Resized_20250923_181406.jpeg
 
I won’t say that Crane never sold those 273 style rockers.
I know they were available from several sources for quite a while.
In the 80’s I put together a 340 using those rockers sourced from TRW.

I’m def not a 273 rocker officianado, but I’ve seen more than one thread on them here referring to oiling issues with them from not using oe shafts(or shafts that duplicate the oe grooves and holes).
Seems as though having the extra hole in the shaft located near the adjuster screw hole in the body is important for proper adjuster screw oiling.

The SB Crane rockers I used(which looked like the rockers in my pics) had the groove in the ID of the body, which provided the oil a path to get from the hole in the bottom of the shaft to the adjuster screw hole and the spurt hole on top.

While priming, once the holes in the cam lined up to allow oil to the top, oil came out of all the holes at once.

Pic showing the groove in the ID-

1C588925-82DF-462C-8CBC-9EB0D552F74F.jpeg
 
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Crane, Isky, Erson and Mopar Performance all sold ductile iron rockers very similar to the original 273 style rockers. In fact, I might be leaving somebody out. There were several different vendors.
 
PRH said:
I won’t say that Crane never sold those 273 style rockers.
I know they were available from several sources for quite a while.
In the 80’s I put together a 340 using those rockers sourced from TRW.

I’m def not a 273 rocker officianado, but I’ve seen more than one thread on them here referring to oiling issues with them from not using oe shafts(or shafts that duplicate the oe grooves and holes).
Seems as though having the extra hole in the shaft located near the adjuster screw hole in the body is important for proper adjuster screw oiling.

The SB Crane rockers I used(which looked like the rockers in my pics) had the groove in the ID of the body, which provided the oil a path to get from the hole in the bottom of the shaft to the adjuster screw hole and the spurt hole on top.

While priming, once the holes in the cam lined up to allow oil to the top, oil came out of all the holes at once.

Pic showing the groove in the ID-

View attachment 1716459315
Click to expand...
I dug out some Isky big block rockers today. I will take one off and look for the groove. The small block ones I have don't have one. Gene.
 

The Isky BB rockers have a groove, as do the Crane BB rockers.
I’ve installed several sets of those thru the years.

IMG_3989.jpeg
 
PRH said:
The Isky BB rockers have a groove, as do the Crane BB rockers.
I’ve installed several sets of those thru the years.

View attachment 1716459678
Click to expand...
Exactly! This is why it's important to put nanner grooves in stock shafts if you're running the stock adjustable rockers. They have no grooves in the rockers.
 
Here is a pic of what my understanding is on how the factory did the oiling for 273’s with adjustable rockers.
The hole that faces down gets the groove, then there is an additional hole that’s up near the pushrod feed hole in the rocker.

IMG_3991.png
 
PRH said:
The Isky BB rockers have a groove, as do the Crane BB rockers.
I’ve installed several sets of those thru the years.

View attachment 1716459678
Click to expand...
I have used more than a few sets too. I checked the Isky BB rockers I dug out. They do have an inner groove like your picture, however it does not connect with either one of the oil holes. I'll try to post a picture tomorrow. Gene.
 
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