engine and drivetrain How To Know When To Change Air Filter?

[gamedeventura]

Hello,

 

I am continuing my first under the hood check of the 1971 2002 I'm looking after, and I was wondering how you can tell if the air filter needs replacing.  I read in a book that holding it up to the light and seeing if light can pass through is a good test, but I think perhaps that method doesn't apply to the kind of filter in this car (or it's just really dirty).  I took the filter out as shown and held it up to the sun.  I think the accordion shape rimmed with cardboard is too dense to check this way.   Was I supposed to try and remove the red parts and then check?  

 

Thanks for the help guys.

- David

Edited January 4, 2014 by HeroOfSpielburg

[Buckeye]

Did you put that in or came with the car? Clean air helps overall performance. Isay toss it and buy a new one < $10 from almost any auto part store.

[M3M3M3]

unless you have service records to know how long the thing has been in the car, chuck it and replace as part of your complete maintenance of everything else.

[Hans]

You'd need to try the test on a new one to get some idea, but they are so cheap you might as well do it every year. I write the mileage on my replacements with a marker as a reminder. AS a stop gap, tap it against the wall -outside- all around.

[Mike Self]

If you have access to a compressor, blow thru the air cleaner from inside to outside--if a bunch of dust/crud comes out, it's replacement time.  

 

Generally speaking, if you drive on paved roads and don't live near an erupting volcano or other big dust producer, a paper air filter element will last a long time without getting clogged.  Oil wetted foam filters (e.g. K&N) need cleaning far more often, which is a good arguement for retaining the factory air cleaner if you're sticking with downdraft carbs...

 

cheers

mike

[gamedeventura]

Thanks for the input guys.  I have no records for how old this filter is, so it's a good idea to replace it seems. In the future the "look through it" and the "tap it on the wall and see what comes out" tests are a good way to check in on newer ones.