User Manual

COMP Cams®
3406 Democrat Rd.
Memphis, TN 38118
Phone: [phone] Fax: [phone]
www.compcams.com
Part #131
Revised 5/10/11
#5100 Camshaft Belt Drive System
Thank you for choosing COMP Cams® products; we are proud to be your manufacturer of choice.
Please read this instruction sheet carefully before beginning installation and also take a moment to
review the included limited warranty information.
If there are any questions or problems during the installation, please do not hesitate to contact the toll
free CAM HELP® line at 1-800-999-0853, 7 a.m. to 8 p.m. CST Monday through Friday.
Belt Drive System Preparation and Installation
:
Step 1: Install the camshaft gear on an old cam, and carefully rotate it into the engine block. Rotate the
camshaft by hand, and note where the gear contacts the block.
Step 2: The front of the engine block above the center oil galley will need to be relieved so that the
edges of the cam gear do not rub the block. It may also be necessary to relieve an area around the 3
o’clock position of the cam tunnel at the edge of the camshaft gear. Grind these areas until you can
rotate the cam freely in the block without the cam gear rubbing.
Step 3: Bear in mind that the camshaft thrust washer is .150" thick, and that any area where the gear
just barely rubs should not need clearancing. With the thrust washer installed at final assembly, the
cam should rotate freely with no rubbing or binding between the engine block and camshaft gear.
Step 4: Before installation, the rear belt guard must be installed on the crankshaft gear. It has a radius
at the back of the gear that should clear all aftermarket crankshafts. It is common to have the bolts tight
in the belt guard itself. A tap or drill can be used to open the holes a bit. We recommend using anti-
seize or a high temperature lubricant on the gear and pushing it onto the crankshaft with a bolt and
sleeve, such as COMP Cams® Part #4920 and #4789. Warming the gear up with hot water will also
aid installation. The crankshaft gear is correctly installed when it is fully seated against the crankshaft
snout. Under no circumstances should a punch or any other tool be used to drive the gear onto
the crankshaft, as doing so will damage the crankshaft gear and crankshaft main bearing thrust
surface.
Step 5: Lubricate the thrust washer on both sides, install it on the camshaft, and bolt on the camshaft
gear using a 0° cam bushing and the stainless steel retainer plate furnished. Carefully feed the camshaft
into the block until the gear and thrust washer are fully seated. Hold a straight edge against the faces of
both the camshaft and the crankshaft gears. Ideally, the two gears should be no more than .025” out of
alignment with one another. If necessary, the rear surface of the crankshaft gear may be machined in
order to improve gear face alignment. Although every effort has been made to ensure that gear
alignment will be within specification, the wide variation between engine blocks makes alignment
verification a necessary step.
INSTRUCTIONS