My bus has an air intake on the driverside which must be for the cabin air. I can't find any information on how to service it, I'm assuming there would be a filter inside there somewhere? I'm including pictures of the outside and inside half of it. There is a air changer vent switch at the bottom too (if you cant read the picture it says "recirc. Air <- | -> fresh air") but I see no way to get in there. Only reason for me getting inside there is because there was a mouse infestation which I got rid of and the fact that this bus was used on nothing but dirt roads most of its life. So I'd like to really like to clean that out. Any advice? It's a 94 international thomas bus
On my bus that is only a fresh air intake vent. Not serviceable in any way and with no filter inside. Only way to get to it is to disassemble the dashboard and heating system. Mine also has a small door on the inside that closes a little bit when I turn the recirculate knob. But it never really closes completely.
If you really want to get creative you might try removing that front vent cover and putting some sort of filter material inside. It's only a few screws from the outside versus a whole disassembly job from the inside.
Ok, that's what I thought maybe I wasnt seeing something. It's just riveted together I'll do a one time cleaning, the other duct work I took off had dirt in it too I'd assume that's where it came from and I will be fitting a filter like you said it seems like a good idea, thanks