Rocker Arm Nuts & Poly Lock Nuts

Using poly lock rocker arm nuts in place of factory-style replacement rocker arm nuts will prevent the rocker arms from loosening. This is due to the set screw tightening against the top of the rocker arm stud, pulling on the rocker arm nut threads against the stud threads, and effectively holding and preventing the rocker arm nut from turning.

Aftermarket high performance rocker arm nuts are made from strong materials, increasing their strength over factory style nuts. This ensures they will not crack or break during heavy and high-rpm use. For example, using 3/8 poly locks for stud girdle (as well as 7/16 poly locks for stud girdle) applications helps to keep the valvetrain in place with increased strength.

Depending on the type of rocker arm nut your engine is using, the steps to remove it will change. You should always follow the procedures in the manual for your specific application. However, in most cases, the first step is to turn the motor over with a socket wrench until the rocker arm is at its loosest point (lifter on backside of cam lobe). This takes the pressure off the valve spring from the rocker arm. Then a wrench or socket will remove the rocker arm nut. If it is a poly lock, or contains a set screw / lock, loosen it first before removing the nut.

If you are experiencing rocker arm nuts that are backing off the rocker stud, the best solution is to upgrade the rocker arm nuts to poly lock rocker arm nuts. However, in many cases, taller valve covers will be required to clear the height of the higher poly locks. It may also be possible to run thicker valve cover gaskets to raise the original valve covers high enough for clearance. This will require careful measurement and test fitting.

Depending on the engine application and the rocker arm nut design, the distance down the rocker arm stud can be different for rocker arm adjusting nuts. Following the valve lash adjustment and nut tightening sequence will put them in the correct position.

When you discover the rocker arm nuts on your engine are not properly keeping the rocker arms tight, upgrade them with poly lock rocker arm nuts as well as additional high performance auto parts from JEGS. Browse our complete selection of rocker arm nut options to keep your valvetrain adjusted properly.