Maintenance and Lubication of 300 Series Strikes Under normal usage the 300 electric strike should be cleaned and lubricated once a year to maintain its reliability. In applications with high usage or dirty conditions, more frequent service may be necessary. Lubrication points are identified in the illustration. When servicing a 300, inspect the internal parts for excess wear for breakage and lightly lubricate per the instructions. Lubricate with HPG Grease , available here. Note: Never lubricate any strike with oil, such lubrication collects dirt and forms an abrasive and sticky compound that may affect the function of the strike. To Inspect and Lubricate the Strike: 1. Remove the strike from the face plate, held on by two (2) 12-24 x 3/8 HEX WASHER HEAD CAP SCS 2. Remove the upper, held on by two (2) 4-40 x 3/16 PHMS.  Removal of the upper cover should be done slowly because the locking cam spring may snap out of place.  Also, care should be taken to insure that the locking cam spacer and locking lever spacer are not lost. 3. Remove the cam spring spacer, cam spring and locking lever spacer. 4. Loosen the two (2) 6-32 x 1/8 SSSC holding the solenoid, then remove the solenoid and locking cam. 5. Remove the locking lever spring and locking lever.  In some versions of the strike, there is a recess in the locking lever and the case for this spring.  In cases with the recess, the locking lever spring must be compressed into the lever before it can be removed. 6. Lubricate the area in the case where the locking lever and locking cam est.  NOTE: Do not get any lubricant on the solenoid or switches.  Lubricate the cam pin and lever pin. 7. Check the locking angle of the keeper and locking lever for wear.  Replace the keeper and/or lever if worn.  If the keeper is disassembled for replacement or adding of a switch, lubricate the keeper pin.   8. Reinstall the locking lever and a new locking lever spring.  Caution: Make sure the locking lever spring is placed back into the recesses of the locking lever and the case.   9. Check the solenoid, plunger and plunger guide for excess wear, dirt, grime or oil.  If present, wipe clean. FAIL-SAFE: Remove the retaining ring for inspection of the plunger guide.  Reassemble the solenoid and plunger with a new retaining ring NON-FAIL-SAFE: Lubricate the bottom edge of the locking cam (contact points of the solenoid plunger). 10. NON-FAIL-SAFE: Lubricate the slot in the locking cam. FAIL-SAFE: Lubricate the bottom edge of the locking cam (contact point of the solenoid). BUY PRODUCT NOW !!