Rocker Info

The removal and replacement of the rocker assembly can be accomplished much less painfully if you follow these simple procedures:

Start by removing 1 valve cover (best if #1-2 side), rotate the engine by hand until it is firing #1 (you can check this either by position of the valves, both will be closed, or position of distributor rotor.) back the engine counterclockwise to 90-100º BTDC which should position all 4 rockers at or near closed valve location.  At this time, removal of the rocker assembly will be possible without putting things in a bind situation.  After removing the 1-2 side, simply rotate the engine 360º and remove the 3-4 side.

Keep this procedure in mind during final assembly, at which time you will place all four pushrods in their corresponding lifters then visually check to see that they are as far down and even with each other as possible prior to installing the rocker assembly.  In this situation, the complete rocker assembly should set down on its mating pad/shim surface.

WARNING! Pulling the rockers down unevenly against severe spring tension can prove to be a serious mistake, damaging the pushrods, adjusters and in some cases, break rocker shafts.

It goes without saying that you should clean everything before proceeding, but we’re saying it anyway. Remove the stock VW pedestal studs by jam-nutting the studs and unscrewing them from the heads. Screw in the replacement studs and slip the rocker assemblies over the new studs. The new rockers have been pre-assembled on stock heads and should sit flat on the pedestal bosses without hang up.

Check for any interference – rocker body to retainer, spring O.D., head casting and valve cover. Check shaft/pedestal assembly clearance and rocker arm body clearance near the cylinder head studs and nuts. Last, make sure the aluminum stand bases are flat and tight against the cast pedestal boss pads of the heads. Any movement here during operation can loosen pedestal nuts, which can snap the studs holding the rockers to the heads or damage shafts. Be certain each rocker arm can pivot freely and does not bind against the springs, retainers, corrective geometry shims or any part of the head casting such as the rocker stand pad area.  It is NOT necessary to laterally (sideways) center the roller tip to the valve tip, 1.5mm (.060”) off-center is acceptable. At this point check side clearances, which should be a minimum of 0.010″ to an optimal 0.015″. Slightly larger side clearances should not be a problem.

With rocker assembly secured to the head without pushrods and at zero lift (valve closed) the rocker/roller tip should contact the tip of the valve or lash cap at approximately 1-1.5mm (.040-.060”) BELOW center.  If it is below center more than this amount, you must shim the rockers out from the head until it meets this dimension.  If it is at center or above center at zero lift, something must be done to increase the valve tip length (add lash caps) or machine the head surface pads where the rockers are held down.  NOTE, this is very unusual and can only be the case if valves or seats are of non-standard configuration causing shorter than stock valve tip-to-rocker pad relationship or if you have aftermarket heads, the pads may be higher than stock or the studs are in other than stock location in relation to guide centerline.  In either case, correcting this problem requires re-machining the pad, relocating the stud or the use of other than our rocker assembly. To continue, ideally roller tip should contact valve tip at .040-.060” below center at 0 lift and .040-.060” above center at full lift.

If shims are required, do not let the shims overhang and interfere with the valve springs, cylinder head nuts or rockers themselves etc. Do not shim adjacent pedestals on the same head with shims of different thickness. This will prevent the roller tips from sitting flat as they contact the valve stems or lash caps and cause premature wear of these parts. Note: hardware store fender washers are NOT flat enough and could cause the rocker assemblies to loosen up and snap the hold down studs.  Shims should be large enough to cover most of the pad in terms of surface area and still clear the underside of the rocker arm body.

After you have set up the proper roller tip to valve tip contact, you can then begin to figure pushrod length needed to complete rocker arm geometry. We like to start this procedure with the adjusting screws turned out about 2 turns from bottoming in the rocker arm body (at the cup end). An adjustable pushrod is then used to establish the required finished tip to tip length.  The correct length places the adjusting screw and the pushrod in line with each other when the valve is positioned at half lift.

You can order pushrods from Pauter assembled to length, or you can cut and assemble them yourself. Just be sure that the ends of the tubes are flat and square so the tips (with interference fit) will seat solidly.  By the way, we favor spherical pushrod tips.

Be certain that whichever pushrods you use are capable of passing oil through tip-to-tip.  The method of lubrication to the rockers, springs and guides depends on this.  While on the subject of lubrication, there are some who believe the method of oil delivery we use is inadequate for this application.  NOT TRUE.  Keep in mind, nearly all small-block Chevys as well as all 9 years of Corvair (horizontally opposed 6 cyl) products use a similar method to this day with great success.

Lube all pushrod wear points with a good moly lube. Install barrel nuts with hex head against rocker stand, round barrel out also be certain to install hardened washers. Torque the 3/8 hold down studs/nuts to 30 ft/lbs. Set your valve lash according to your camshaft spec card.  Set aluminum pushrods use factory specs. Steel pushrods should be set COLD at .000?-.001? Operating clearance will be achieved through thermal expansion.  Caution, setting valves when hot may cause them to open when cold.  At this time, take a long look at the pushrod to pushrod tube for possible interference.  You should have at least 1mm of clearance throughout a complete engine rotation cycle.  Check all 8.  If interference is a problem, it may be possible to shim the rocker arm to one side to clear.  As we stated previously, it is not necessary that they are perfectly centered on the valve tip.  If stock pushrod tubes are used, sometimes just carefully tweaking them may be enough.  If these methods are not sufficient, the use of larger aftermarket tubes should work.  Further interference may require the addition of tapered pushrods.

In most cases when using Type 1 head castings with standard length valves, stock Type 1 valve covers will work.  The long hold down nuts supplied with the kit will allow you to use bolt on valve covers, be sure the valve cover bolts you use have 3/8-24 threads.   Be certain to check for any interference of rockers (particularly the adjusters) to valve cover prior to bolting them down completely.  After initial operation and the engine has cooled to ambient temperature, inspect the valve train, re-torque stands and check valve adjustment.