Small Block Rocker Arm Oiling

OK just went around there again this morning.

The rocker gear has been removed now and there is a quite big difference in the oiling arrangements between the W2's and the stock arrangement.

Fundamentally, on the std heads, at the top of the rocker stand is a recess around the bolt to provide oil to the shaft. This recess intersects with the oil gallery coming up through the head.

On the other hand the W2's have a VERY small (say 1-2mm) gap on the lower side of the stand (maybe 4mm wide - the bolt hole basically covers the passage for oil to the rocker shafts. Forgive my ignorance, but is this "normal" it appears to cause a massive restriction in the oil system.

I'll try and post some photo's shortly.

from what you're seeing does it look like a smaller shank bolt at the bolt head or opening the shaft hole or?? will let it flow more

The W2 hold down bolts are a larger diameter than the std type but the principle remains.

We have thought about turning down the W2 bolts on a lathe, but not sure if that will weaken them too much.

Just trying to work out how to add photo's...I know there's a thread around here somewhere about it....

OK here we go... stock first.

Note the gap between the bolt and the head casting.

click edit then put a checkmark in the lower of the (3) boxes & click "change this post" then click on "browse" & select the pic out of your file where they are stored & click on that pic & it's address/name will load into the vacant white rectangular address bar. Not sure what your dimentions are but opening the shaft bolt hole dia or a smaller bolt just as long as the psi is contained from leaking out plus not restricted to flow into the shaft or at least the restriction opened up enough to get the flow you need.

Working on a convoluted way of adding the photo's one down another to go!

Here's the W2 version quite obviously an issue getting oil to the rocker shafts with this arrangement.

Side view of the W2

Ok, last one, back to stock now.


Note the thread for the rocker shaft bolt only starts about 1/4" down the bore.

On the W2, the threads go right up to the top of the stand

I'm thinking if you drilled a hole down alongside the threads for the oil to get past the bolt threads but 1st not being familiar w W2's that is a pedestal just like LA's (it's shallow in the pic & hard to tell) & the only diff (as far as valvetrain is the offset rockers right? or are the stands offset also?). What I'm missing is what bolt do the stock w2's use that lets the oil flow past it? EDIT just saw your latest pics. I'd drill the notch in the W2's & unless I am missing something I think that'd b a simple fix. You'd lose a little bit of thread engagement but that wont hurt you. W care you could temporarily plug below your drilling to keep shavings out.

I think there's three options - all have issues as my mate is reluctant to take the head(s) off.

1 - Over size the top portion of the rocker pedestal thus creating an area around the bolt that oil can flow through (per std arrangement).

Issue - Need to somehow prevent getting filings everywhere, incl down the oil gallery.

2 - Machine the Bolt Down on a lathe in the area where the oil flows out of the pedestal.

Issue - Need to ensure bolt retains enough strength to effectively hold rocker shaft.

3 - file back the oil gallery so oil flows straight into the rocker shaft.

Issue - Unclear whether this will provide sufficient oil.

I think you can get it WO taking the heads off. Plug the hole below where you are drilling/coat the bit w grease/duct tape etc to collect errant shavings & if you turn the bolt you can use a higher grade one. EDIT turn the drill slower to keep shavings from being flung out

I dawned on me yesterday as to why these W2's have this problem. I reckon the rocker stands were delivered per the standard configuration and have been subsequently milled down flat for the W2 rocker stands (aluminium blocks). This would have effectively removed the area for oil to reach the stands in question.

Anyway, he has now oversized the hole around the base of the bolt and widened out the area where the oil gallery comes up through the head. Hopefully this will provide sufficient room for oil to pass through the head into the rocker shafts.

Will fire it up later today and report back. Still have to do the other side, assuming it has the same issue.

Back in the early 80's when I did a W2 motor, I fried some arms and pushrods from lack of oiling. I had used the bushed arms from D/C and also the shafts plus the semi-finished pushrods. I did some checking and it turned out that even though the shafts were from D/C for the W2 application, not the regular heads, the oil holes were miss drilled 90*. The arms would have had to be straight up and down with the rocker tip pointing at the crank to get oil. By chance I had contact with one of the gents who designed the heads for Ma Mopar, Lee Muir at Chryslers west coast skunk works Shadow Racing, and he told me that Mopar made a bunch of these shafts with this screwup and did nothing to remedy it. I ended up replacing some arms, both shafts, some pushrods and ground in some light grooves into the shafts for oiling. With the heads assembled, stick a wire into the oil hole that squirts the valve, when the valve is closed, and see if the arm and shaft holes line up. If they don't, bingo! Just because D/C makes the stuff, it doesn't mean its going to work properly. Lee Muir developed these heads with the King, #43, and it was a MAJOR HONOR to meet this guy who did all this neat stuff way back in the Can-Am, Formula 5000 and REAL NASCAR days. This was the engine that was originally in Diego Teds, my old, Duster.

Hi All,

Sorry to exhume an old thread but my mate has come back to me with some issues.

Easy question I hope - does the hole in the shaft need to intersect with the hole in the rocker through some part of its travel to get a squirt of oil to the top of the pushrod, or is there (or should there be) sufficient pressure there to provide oil to that area. I suspect the answer is the holes need to align but I'd like some clarification.

Thanks

Shannon

I did not go back through this string but if you make sure to have the notch in the rocker shaft end down and forward on the left (drivers side) and down to the rear on the right (passenger side) side of the engine all will be well. If you don't have oil to the top then you have a misaligned cam bearing or oil galley plug missing. Remember that the engine only oils to the top in certain positions of engine rotation and then to alternate heads. Both do not oil at once.

Howdy, thanks for that.

Yep all of that seems to be correct and we definitely have oil in the shafts, but there's a couple of rockers that appear to be dry(er) than the others. However the notch is more of a grind mark than a notch (Mopar shafts).

In particular it appears that the offset (intake) rockers are more affected than the straight ones.

There's a long and painful back story to this regarding using econo rocker shafts and having to oval them out to fit race W2 arrangements etc. etc etc so my question really is as simple as;

Does the hole on the rocker arm, have to come into alignment with the hole in the shaft, for it to oil the pushrod?

On mopar engines big or small block the stamped rockers are all offset one way or the other. Put the left hand rocker in left hand right in tight hand and work your way around the vehicle. I always start on the drivers (left) side. Left towards front on left side and to rear on pass side.
Pictured is small block:

Yep got all that, we're OK with that.

It just appears to us that a misalignment of the two holes in the rocker and the shaft isn't allowing the oil to escape to oil the top of the pushrod. There appears to be oil everywhere except at the top of the pushrod.

I've attached a picture to try and explain what im on about!

Shannon

Oh OK I see what you are sayin. The hole(s) could very well have been drilled wrong. I would check another set of rockers to confirm & you may need to redrill em at the right clocking. On a side note iirc the DC manuals want the ball to be 9/32" below the rocker tip for the oil stream to be aimed correct and a straight line from the hole like a laser beam in a bullet hole goes right alongside/touching the surface of the rocker arm pad that contacts the valve stem and Hughes engines has an informative orange sheet on pushrod length/alignment etc. That's all I know. Post how it goes. EDIT The small holes in the bottom side of the shaft(s) you have them offset slightly (15 deg) toward the valve side correct? and the only other holes in the shaft are the (5) top/bottom large holes for the mounting bolts. post where the (2) holes in the rocker arm are (the (1) on one side for the pushrod cup and the (1) on the other side for the valve stem tip)