Tools & Materials
Your planer's feed rollers are driven by chains and sprockets. The outfeed roller has two sprockets on it: one connecting it to the gearbox, and the other connecting it to the infeed roller. The infeed roller has a single sprocket. Over time, the sprockets can wear, causing the chain to skip. If the planer is frequently overloaded, the key on the sprocket might shear.
Let's get started.
REMOVING THE OUTER SPROCKET 1. Remove the side covers.
a. Remove the two screws securing the left (side) cover to the planer.
b. Pivot the upper portion of the side cover toward the planer and lift the side cover until its bottom portion clears the rail on the frame.
c. Remove the left (side) cover from the planer.
d. Repeat this step to remove the right (side) cover from the planer.
2. Raise the cutter head.
a. Use the crank handle to raise the planer's cutter head to its highest position.
3. Tilt the planer.
a. Carefully tilt (and lay) the planer on its front.
4. Remove the chain cover.
a. Use a short (stubby) Phillips screwdriver to remove the two screws securing the chain cover to the housing.
b. Remove the chain cover from the unit.
5. Remove the outer chain (and sprockets).
a. Use snap-ring pliers to remove the retaining rings from the two outer sprockets.
b. Slowly and simultaneously slide the two outer sprockets (and the outer chain) away from the roller assemblies.
c. Remove the sprockets from the outer chain.
INSTALLING THE NEW OUTER SPROCKET
6. Install the outer sprocket.
a. Install the chain onto two sprockets (the new sprocket and the original). Both hub stems should face the same direction (toward the rollers).
b. Align the hub key of the left-hand sprocket (the one that attaches to the outfeed roller) with keyway on the roller shaft and press the sprocket partially onto the shaft.
c. Align the right-hand sprocket with the shaft of the infeed roller and rotate the infeed roller until the hub key (on the sprocket) aligns with the keyway on the roller shaft.
d. Press both sprockets firmly onto the roller shafts.
e. Secure the two (outer) sprockets with the retaining rings.
REASSEMBLING THE UNIT
7. Reinstall the chain cover.
a. Install the chain cover.
b. Secure the chain cover with the two screws.
8. Reinstall the side covers.
a. Install the top portion of the left (side) cover.
b. Lift the side cover until the bottom portion clears the rail on the frame.
c. Press the side cover down until the bottom portion seats behind the frame rail.
d. Secure the left (side) cover with the two screws.
e. Repeat this step to install the right (side) cover.