Rock-afire Mac Valve Maintenance
An official procedure for MAC valve rebuilding is documented in the ShowBiz Pizza Place Operations Manual from 1981.
- Remove snap ring or spiral ring from top of spool
- Remove plastic cap and spacer
- Carefully remove the spring and spool trying not to damage or scratch up the inside metal
- Inspect the spool to make sure there is no dirt or debris in the mac valve casing or spool
- Remove and replace the 2 O-Rings on either side
- Clean the spool and casing of old grease with water and soap
- Lubricate the spool and casing with white lithium grease
- put the spool in the casing being sure the hallow end is facing up
- place spring into the hole at the top making sure it goes in strait and there's no obstructions
- place small white spacer onto spring making sure it is strait
- place white cap on top of white spacer being sure the groove lines up with spacer
- push down on cap and put the snap or spiral ring on making sure it went to the locking groove
