Crane Ductile Rocker Oiling Question

[threewood]

This may be stupid but I have thinking about it all day. I have a set of the Crane ductile iron rocker arms on my 440 with thick, hardened rocker shafts. The oiling holes in the shaft are on the bottom and grooved to oil the entire width of the inner rocker arm.

Inside the rocker is an oiling groove that covers 360 degrees. Now, here is where it gets confusing. There are two oil passages, one to the top of the rocker and one to the threaded adjuster. My guess is these oil the pushrod cup and valve tip. However, there are no corosponding oil ports in the shaft and I cannot see how oil gets to these passages!? Is there enough pressure to get oil into these along the shaft? Do I need to groove my shaft for these as I did for the lower oil port?

Grooved shafts...

You can see the port on top of rocker and on adjuster. These have no direct feed...

 

[moper]

The oil comes from the shaft to the rocker, that 360* groove directs oil to the tip and adjuster. None of these get oil 100% of the time. Only for a few crankshaft degrees of rotation when the oiling holes in the cam line up to connect the oil feed to the passage up to the heads.

 

[70bigblockdodge]

Oil passes up from number four cam bearing into a passage in the head that runs in the dividing wall in the intake ports and flows into the rocker shaft from pedestal through enlarged bolt holes in each once every other revolution as mentioned above

 

[threewood]

The oil comes from the shaft to the rocker, that 360* groove directs oil to the tip and adjuster. None of these get oil 100% of the time. Only for a few crankshaft degrees of rotation when the oiling holes in the cam line up to connect the oil feed to the passage up to the heads.

But the tip and adjuster ports are not in the 360* groove, they are located on the flat bearing surface of the rocker arm. They dead end into the shaft which is why I was asking.

 

[Brewzer67]

There will be residual oil that gets dragged to the top of the rocker by virtue of the rocker rotating on the shaft and capillary action. The hole represents the path of least resistance so the oil finds its way out under pressure.

 

[khryslerkid]

I answered this once before.

http://www.forbbodiesonly.com/mopar...-quick-questions.120049/page-4#post-910540418

 

[threewood]

There will be residual oil that gets dragged to the top of the rocker by virtue of the rocker rotating on the shaft and capillary action. The hole represents the path of least resistance so the oil finds its way out under pressure.

Ok, so the two oiling holes are not suppose to get direct oil like the rocker bodies, and they just dribble oil out?

 

[threewood]

I answered this once before.

View attachment 433983
View attachment 433984

http://www.forbbodiesonly.com/mopar...-quick-questions.120049/page-4#post-910540418

That is a good thread, thanks! So where the oiling holes end on the bearing surface inside the rockers. ..they are not suppose to align with any hole or slit in the rocker shaft?

 

[khryslerkid]

That is a good thread, thanks! So where the oiling holes end on the bearing surface inside the rockers. ..they are not suppose to align with any hole or slit in the rocker shaft?

The oil being under pressure between the rocker and the shaft finds its way around the shaft and out the oil hole at the adjuster. Oil coming out the hole at the adjuster lubes the pushrod tip as it runs down the pushrod.

Just make sure to install the shaft with the oil hole at the bottom and angled to the outside of the head. You can see that the 3/16" oil hole is off center on the shaft.

 

[Brewzer67]

Ok, so the two oiling holes are not suppose to get direct oil like the rocker bodies, and they just dribble oil out?

That is somewhat correct. The rocker gets fed from the shaft, and the holes in the rocker leak that oil that is fed to the rocker to the pushrod cups and to the spring side of the rocker.

 

[moper]

They don't need a bunch of oil. It's just dripped and splashed on the tips and pushrods.