A/C System Filter

[Kempo]

I was working on installing the A/C on my GTM last night. I noticed how hard it would be to service the unit after the car is finished. Having the blower located outside the cabin under the hood will pull a lot of dirty air in the system. Even having it inside with Shane's solution will in the long run get dirt and grime on the evaporator making it less efficient and maybe even making it fail given the fact that it is made of aluminum.


I know this cars are not daily drives and won't be subjected to as many hours of use as other vehicles but I just want to get the odds of having to service it as low as possible. I'm planing on making some kind of filter I can put over the blower to help on this issue plus making it less noticeable in the passenger foot box. Maybe another solution could be making some kind of slot on Shane's relocation duct to insert some kind of filter. I'm no engineer so I'm sure most of you could come up with something better than I could (hint,hint) If someone does please put me down for one.

[VRaptor SpeedWorks, LLC]

Production cars have been running around for many decades now with no filters on air thru the evaporator. The whole HEPA filter on production cars didn't really start until the 2000's. The evap core is essentially "self cleaning". As the dust and dirt settle on the condensation of the evap, it is "washed away" as the evap continues to sweat and drain out the drain tube.

[Kempo]

That is exactly the reason why so many evaporators had to be replaced prior to using those filters. That same condensation that "washes away" that dirt leaves some dirt behind and eventually clogs the evaporator. Is not only the dirt is also hairs,fibers etc.

[VRaptor SpeedWorks, LLC]

I've got a '94 Toyota Pickup with 170k miles on it. I live on a gravel road. The AC will still freeze you out. In 4 years working as a mechanic in a dealership, I've never replaced an evap core because it was clogged with dirt. Mouse nest (complete with dead mice)....yes. Build-up of dirt or fibers.....no.

[mmaragos]

I left the blower in the stock location, but sealed it up. It only draws air from inside the cabin. I am planning on putting a filter at the inlet in the cabin. :)

[Monty_GTM]

Has anyone found a good way to bring fresh outside air into the cabin and circulate it via the heating/cooling vents?

When you're cruising and don't want the windows open (noisy and/or when it's raining) and it's not hot enough for AC, a nice fresh freeze would ne nice :) Fresh air is healthier than constantly recirculated cabin air, especially during long trips.

[tirod]

The cabin isn't sealed airtight - even on recirc you pull in outside air from seals leaking, etc. Especially on a kit with tube frame - there is no sealed airtight firewall like a unibody or cab on chassis production car.

If anything, the HEPA filters were installed because "fresh" outside air - isn't. It's hay fever season right now here, the "fresh" air is loaded with ragweed pollen, and we who suffer keep the windows up and air in recirc to reduce the inbound irritants and contamination. Same when you follow a cattle truck, or drive on a dirt road - windows up when you come to a stop or follow someone within a country mile. It stops loading the interior air with an increasing amount of dust, odors, diesel smoke, or spray trucks fogging for mosquitoes.

Long trips, recirc, especially in the summer. Owner's manuals don't advise it, the problem is on production cars the a/c is so good it can chill the interior below 70, then you get out and are smacked by 90+ degrees and 90+ humidity. Route salesmen have been known to keel over in the heat as their overweight constitutions max out from the sudden impact.

A kit owner should have it so bad - the common complaint is that they can't even keep the rain out, it leaks thru every nook and cranny forward. Dry, so does the air, even in the winter, which so few actually attempt in the kits. It's been estimated a kit has so much surface area open to pass air into the cabin it's worse than removing the blower and heater core, leaving a gaping hole under the dash. Having driven like that in subfreezing temps thru a snowstorm to get to a drill weekend in the Reserves, I can testify that even long underwear and issue Artic gear isn't enough.

Don't kid yourself, these cars get plenty of fresh air, rain, dust, smoke, gasoline fumes, etc. Even our daily drivers can't keep out the smell of garbage truck dead ahead.