How do you tighten roller rocker arms?
Do one cylinder at a time and make sure your lock is backed out. Turn your motor over until your exhaust rocker just starts to press down on the valve spring, that is when you will adjust your intake valve for that cylinder. Spin your pushrod while slowly tightening the nut on the rocker. Do not over tighten it.
How much valve lift do rocker arms need?
High lift aftermarket rocker arms or a high lift cam may require using different springs that allow increased spring travel. Some springs cannot handle a maximum valve lift of more than .550″. For higher lifts, different springs are required. Follow the spring supplier’s recommendations when matching valve springs to maximum valve lift.
Why are rocker arms used on an overhead valve engine?
Rocker arms are installed on all overhead-valve engines and transmit lifter movement to the valves. Because the rocker arm is essentially a lever, the length of the rocker (its pushrod contact point to pivot), increases valve lift relative to cam lobe lift.
How big of a rocker arm do I Need?
For small block street performance engines with a flat tappet cam and no more than .450″ of lift, single springs with 80 to 90 lbs. of seat pressure with the valves closed are usually adequate. For street/strip performance engines, springs with 100 to 120 lbs. of seat pressure are usually recommended.
What happens if you twist the rocker arm?
If the rocker arm twists, it may bend the pushrod and/or allow the tip of the rocker arm to walk off the side the valve tip. If that happens, the rocker may push down on the retainer instead of the valve, causing the locks to pop out and the valve to disappear down the guide, destroying the engine.
Where are the rocker arms on an engine?
Rocker arms are typically located between the pushrod and intake and exhaust valves. They are pushed and pulled by pushrods to “rock” up and down, opening and closing the exhaust valve and intake valve of the combustion chamber on engines with a camshaft below the engine.
When do you need to replace a rocker arm?
Rocker arms are a lesser-known but crucial part of some types of internal combustion engines. Their deterioration can cause weak engine performance or even failure, so it’s important to know when replacement is necessary and how much the rocker arm repair cost will set you back. What is a Rocker Arm and How Does It Work?
How can I tell if my rocker arm is bad?
Visual inspection of the rocker arms can also reveal any cracks or wear. After removing the valve cover, look for pieces of metal below the rocker arms, as they can grind on the pivot point and valves when they are in poor condition.
Is the stud on the rocker arm nonadjustable?
If the rocker arm is stud-mounted, such as on a Chevy, then proper procedure involves attaining zero lash plus the specified amount of preload. Some engine designs, such as the Pontiac V-8, use a stud, but are considered nonadjustable in factory form.