COMP Cams 8959-16 Hydraulic Roller Lifters - Manual (Page 2)

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COMP Cams®
3406 Democrat Rd.
Memphis, TN 38118
Phone: 901.795.2400
Part #COMP4-140
Revised 3/22/12
Toll Free: 1.800.999.0853
www.compcams.com
3. Pushrod and rocker arms: Clean all pushrods thoroughly because most engines oil through
the center of them. If the original pushrods are being used, be especially sure they come clean
inside and out. Apply a small amount of COMP Cams® Engine Assembly Lube (Part #102) or
an equivalent lube on each end of the pushrods, and install them into the engine. Clean all
rocker arms thoroughly. If the original rocker arms are used, examine each one for excessive
wear, and replace any that are questionable. Apply a small amount of lube on all contact areas
of the rocker arm. With a clean rag or towel, wipe the tips of the valves clean and apply lube to
them where the rocker arms will come in contact with them. Also be sure to check the valve
stem tips for excessive wear. Next, install the rocker arms. Make sure the pushrod is in the lifter
and the rocker arm seat when making valve adjustments.
4. Adjusting pre-load: COMP Cams® Hydraulic Roller Lifters can be used with adjustable and
non-adjustable valve train designs. However, each type of valve train has its own set of
procedures for setting pre-load. This section is divided into two parts: Section I describes
adjusting pre-load with an adjustable valve train, while Section II explains adjusting the valves
using a non-adjustable valve train.
Section I. Setting pre-load with ADJUSTABLE ROCKER ARMS
Turn the engine in the normal direction of rotation. Start with cylinder number one (1). When the
exhaust valve begins to open, adjust the intake valve to the correct pre-load. To reach zero, take the
pushrod between your finger tips and move it up and down while you tighten the rocker arm. Once
you feel the pushrod has no more vertical slack, you are at zero pre-load. Make sure the pushrod is
in the lifter and the rocker arm seat when making valve adjustments. As stated before, the
recommended setting is 1 turn of the wrench on the rocker arm adjusting nut past zero. Now, you
can move on to the exhaust valve on the same cylinder. Begin by rotating the engine over again
until the intake valve reaches maximum lift and is almost all the way back down. Then set exhaust
valve using the same method as the intake (1 turn of the wrench past zero). Continue adjusting the
valves on each cylinder in this manner until all valves are adjusted.
Section II. Setting pre-load with NON-ADJUSTABLE ROCKER ARMS
A different procedure and measurement is required to set hydraulic lifter pre-load on engines with
nonadjustable rocker arms. First, install the pushrods and torque all rocker arm bolts down in the
proper sequence and torque specification. Rotate the engine by hand in the normal direction of
engine rotation until both the exhaust and intake valves have opened and closed completely. Allow
a couple of minutes for the lifters to bleed down.
Using the valve cover gasket surface on the head as a reference point, place a mark on the pushrod.
The smaller, more defined the mark, the more accurate the measurement. Be sure the reference
point you choose for the first mark is easily accessible and easy to duplicate. The pushrod will be
marked twice. It must be from the same reference point and angle for the measurement to be
accurate.
Loosen the rocker or rocker shaft bolts. Leave the rockers on the head so that they will support the
pushrods. Be sure the pushrods are standing free in the lifters and do not have any pre-load. Using
the same reference point, place a second mark on the pushrod. Make sure the angle and reference
point are the same as the first mark.