The Mac Valve has an internal rubber plunger which opens and closes the ports which allows air to pass through to a cylinder, air pump etc.. The following can cause the plunger to stick:
- Moisture -- It is important to make sure you have a refrigerator dryer inline with your compressor. The dryer is used to eliminate any moisture out of the air lines. It is also recommended to have an additional Filter before the air gets introduced to the mac valve. In these cases we will use an FRL (Filter Regulator Lubricator)
- Using the incorrect lubricant in the lubricator bowl (FRL) -- Using the incorrect lubricant, like WD40 and other similar oils, in the lubricator bows can cause the seals/rubber in the mac valve to swell and get damaged.
- Debris -- Debris in the lines can cause the plunger to stick. Open the valve carefully and flush out any debris out of the valve body. You can use air to clean the valve ports and body.
NOTE: Mac Valve recommended lubricants.
Manufacturer Oil Number
NFO NFO 10 H/NR
NFO NFO 10 W/NR
Chevron AW10 Machine Oil
Chevron Handy Oil - 15
Exxon Teresstic 32
Mobil Mobil DTE Light
Mobil Dexron II ATF
Mobil AFT 210 Type F
Mobil DTE 13M
Mobil Almo 525
Mobil Mist Lube 24
Mobil DTE 24
Mobil Hydraulic Oil 13
Mobil Hydraulic Oil AW 32
Wolverine A-Industrial 150 R&O
Titan Type F ATF
Tital Dexron II ATF
American Industrial Oil 32