Operators, make sure you keep a close eye on the 621G scraper’s cab air filter, especially after a heavy rain.
The filter’s access door has a series of louvers that allows open air flow. Problem is, the louvers also allow water from rain and cab run-off inside the door. That water fills the channel along the inside bottom of the door.
If there’s too much water, it overflows the channel and the air filter soaks it up like a sponge. A soaked filter element gets moldy real quick!
You may also see buildup from water that seeps past the drain hoses attached to the A/C drip pan.
The hoses are installed with a grommet that fits into a hole in the plastic drip pan. But the grommet doesn’t fit tight and the silicone sealant holding it in place gives way from vehicle vibration.
Here’s the bottom line. There’s a fix in the works to get rid of the water. But in the meantime, make sure the air filter element stays clean and dry. Replace a wet or moldy filter with NSN 4330-01-602-0614. If it’s just dirty, clean the filter with low-pressure air (30 psi or less).