429 Shaft Rocker lubrication

[Necro-Engineer]

Hi,
I have a 1966 cadillac ambulance/hearse combination car. The car has a 429 that i'm in the process of rebuilding. My Cadillac shop manual states that the shaft rocker system recieves oil from the block and in turn lubricates the rocker arms and valve tips. For the life of me, I cannot seem to figure how the oil gets from the heads to the interior of the rocker shaft. Can someone enlighten me as to how this takes place. I feel pretty certain it is not achieved by elven magic. lol

[Guidematic]

There are oil passages in the block that mate with oil passages in the head. The oil is then carried up through rocker shaft mounts and down the rocker shaft which in turn lubes the shaft. I'm not too sure on this, but the rockers may be drilled and timed shots (much in the same manner the crankshaft and rod journals are lubricated) of oil are sent to the ends of the rockers to lube the push rod end. Splash and spill off lubes the valve ends.

The 1967 429 is unique in that it uses the same pedestal set up that the 472/500 uses. Oil is sent up the push rod in the same manner the Chevrolet engines use. The splash and spill off then lubes the pivot and the valve end.

Mike

[Necro-Engineer]

thanks for the reply,

So what you are saying is there should be an oil passage hole in the bottom of the rocker shaft pedestal and one in the head where the rocker pedestal attaches to the head? I thought this should be the case. However, I can find no oil passages in the heads or the rocker pedestal. I might add that the pushrods on this engine are solid. There are no oil passages in the pushrods either. How is this engine lubricating the rocker assembly?

Can you give me some ways to identify what the year of this engine is. My '66 book says there is a stamp on the rear of the left cylinder bank just under the head, but I can't seem to find it.
Thanks again

[paul]

i think the engine # is just behind the intake manifold on the back upper part of the block 65 to 67 inbetween the 2 top transmission bolts but on the block. Im thinking thoe rocker shafts are the same from 58 to 66. i always thought the oil traveled up the push rods, could be wrong. 67 429 has the pedistal type rockerarms like they used on the 472s and 500s. engine #s are 49 to 58 on the RH side at the front of the head on a embossment. 59 to 64 on the left hand side of engine block in the center just ubove the oil pan lip. most likley all covered with gunk and oil.

[Guidematic]

I am quite sure on this one. Only the '67 has the oil passing through the pushrods, and you have to be very careful in your purchase of lifters for this year. Make sure they have the holes in the plungers to supply the oil to the pushrod or the valve train will run dry and self destruct.

Mike

[Joe 12138]

Looking closely at the oil flow diagram, which is shown on the first page or two of most 1949-1966 shop manuals explains MOST of the question. The oil passages are drilled into the block and heads, and 1/8 " pipe plugs seal the openings. The oil passages are usually at 90 or 45 degee angles to each other, as on cannot drill around corners. Look at the oil flow drawing closely......wherever there's a change of direction, there will be a pipe plug on the exterior.
       So, the main question here is "How does the oil get from the head casting to the rocker tube?".  The Bolt that holds the rocker assembly to the head is necked down (reduced in size) as copared to the threaded part. This reduced diameter section passes THROUGH a horizontally drilled oil passage in the head casting. The oil volume  is metered by the area between the bolt shaft and hole in the rocker standoff casting. The oil flows vertically UP one standoff per head. It enters the tube, and gets ditributed to the individual solid pushrods as someone else decribed earlier.
        The amount of clearance in the necked down area of the bolt is critical, so sustituting a generic rocker bolt on any OHV Caddy engine can be bad news if the oil passage is restricted due to not having the bolt shaft's diameter smaller the threaded part, both at the oil entrance at the head casting, or the discharge point at the rocker tube itself.  Again, look closely at that oil flow diagram.....there's more there to see than most people realize at first glance!  Next question?  Could I remove those pipe plugs to clean out those oil passages in the head? You bet!!!! 

[Coupe]

In addition to Joe's comments, the rocker shaft HAS to be oriented properly to allow oil distribution to the rockers. Your shop manual will describe this in detail. If '66 is the same as '57 there is a small reference notch in the end of the rocker shaft that has to face downward towards the valley. Another item to check is the rocker shafts themselves. Most likely sludge will have built up in them.  The plugs in each end are similiar to frost plugs. You will have to get new ones once they are removed.