Oil Through Push Rods? '73-440, oem Rockers, Howard's Lifters

[greycharger]

I need to order in push rods from Jegs as they are the only vendor I have found with the fuel cell filler neck I need and I want free shipping for $100 order.
I've scanned the threads, but found nothing definitive. Apparently, the Push Rods do not need to oil the Rockers? I have Howard's 91711 lifters (AMC / Mopar so they have the oil holes), new OEM Rocker Arms on 452 heads, Comp Cam dual springs, 268/289 XE Camshaft. I am assuming 5/16 diameter/9.31 length. Jegs says that 1973 440's did not put oil through the push rods.
Info? Options?

 

[R/T Boy 67]

Mopars of that era did not oil through the pushrods. The rockers received oil through a passage into the rocker shafts.

 

[greycharger]

Seems odd, but the shaft and rocker socket must get sufficient oil or they wouldn't have done it that way.

 

[beanhead]

R/T boy is correct...oiling through the rods can be done but isn't necessary, unless maybe it's a higher performance build.

I am assuming 5/16 diameter/9.31 length.

Correct on the diameter..I would strongly suggest measuring for pushrod length though, especially if machining has been done to the block and/or heads. If you find you need a different length then what is sold off-the-shelf, contact Manton or Smith Brothers they will make you a set to fit. A little more expensive but if your pushrod length is too far off you can have all kinds of issues..

 

[R/T Boy 67]

With a stockish setup, it works fine. Just as a side note, hyd. lifter slant 6 engines oiled through the pushrods in a reverse sort of fashion.

 

[PurpleBeeper]

Seems odd, but the shaft and rocker socket must get sufficient oil or they wouldn't have done it that way.

Sure enough. If you look at the holes in the heads where the rocker shaft bolts go, #2 & #4 (so to speak) have bigger than necessary holes for the bolts (oil comes in the bolt-to-hole gap). That oil gets inside the rocker shaft (hollow tube) and that shaft has some small "sprinkler holes" all along the bottom....sort of like a "slow drip garden hose" with holes all along it to water your garden.... and that's where the rocker arms get oiled. It's an unusual design for sure.

The lifters get oiled "from the sides" from lifter galley holes in the engine block. The pushrods can just be "solid rods" in most cases....except as other guys have mentioned.

 

[69Bee]

R/T boy is correct...oiling through the rods can be done but isn't necessary, unless maybe it's a higher performance build.

Correct on the diameter..I would strongly suggest measuring for pushrod length though, especially if machining has been done to the block and/or heads. If you find you need a different length then what is sold off-the-shelf, contact Manton or Smith Brothers they will make you a set to fit. A little more expensive but if your pushrod length is too far off you can have all kinds of issues..

Comp Cam pushrods can be ordered by a size, and stock pushrods can usually have a 0.060" shorter and longer for these issues. I have used Manton twice, and they were awesome. I had a set made for a Bentley/RR engine, and saved the customer about $1000

 

[wyrmrider]

Oil through the pushrods never hurts
it can help with the pushrod push through the rocker problem
stock pushrods for stock springs
higher pressure springs and faster action cam go with the hollow pushrods

 

[greycharger]

Oil through the pushrods never hurts
it can help with the pushrod push through the rocker problem
stock pushrods for stock springs
higher pressure springs and faster action cam go with the hollow pushrods

Can't find anybody who makes them. Just spent 45 minutes looking for 5/16 oil through push rods.

 

[69Bee]

Comp Cam 7789-16 for OE length 9.300", 0.080" wall https://www.summitracing.com/parts/cca-7789-16
Comp Cam 7788-16 for 9.250 length (-0.050"), 0.080" wall https://www.summitracing.com/parts/cca-7788-16

Help from you not so local machine shop...

 

[BSB67]

Today's lifters are already challenged to do the simple task they were designed to do. That is to not bleed down oil. I think giving the lifter one more unnecessary job of oiling the rocker is totally unnecessary. I think 4 million BBM ran without pushrod oiling. I've never heard of a mild BBM application that had a rocker problem that needed PR oiling to solve.

Honestly, there is a limit to everything that is more is better.