Air Cleaner Indicator

[Bird]

<font color=blue>where did this misinformation originate from</font color=blue>

John, I'm afraid I've never quite been able to accept that theory myself; that a filter is better when it's a little dirty, but in '95, while talking about my B7100, a Kubota factory rep told me, "Don't be in any hurry to change the air filter." He said it was better when it was a little dirty./w3tcompact/icons/frown.gif The B7100 only had the one filter instead of an innner and outer. Now the B2700 has the two filter system and when I ordered the inner filter from a dealer, he asked why I wanted it; said no one ever changes that inner filter so he didn't stock them./w3tcompact/icons/shocked.gif I told him, "I do." So he ordered it for me. I suppose it's possible that I'm wrong, but I still like clean filters./w3tcompact/icons/wink.gif

 

[Anonymous Poster]

<font color=blue>...never quite been able to accept that theory myself...</font color=blue>

Hi Bird,

I guess when I open up my next air filter package and they have a "small container of fresh dirt enclosed with explicit instructions of sprinkling gently over air filter before installing..."

I could change my mind... but I won't... /w3tcompact/icons/blush.gif

 

[GlennT]

Just picked up an indicator for my JD 670 yesterday. I had to buy a new one because we have no salvage yards locally. The indicator is a Donaldson and it cost $27.02 plus $1.75 freight. Hope it works.

 

[GaryK]

Don't know if this helps, but to reset most of these indicators all you have to do is push the end of it. You could be doing this inadvertenly, you could have a vacuum leak in line that the indicator is attached to or the indicator is defective.

 

[cowboydoc]

gvw,
I've noticed the same thing. I recently replaced the one on my pickup and the indicator never moved. I took it out as part of my 6 month maint. and it was terrible. I can't believe that anyone would recommend that being in there. I've since talked to some mechanics and they have said the same thing that you found that they are basically like the idiot lights and you could still have a problem even though it isn't indicated. If they do go off you may or may not have a problem and if they don't go off you may or may not have a problem.

 

[MChalkley]

gvw - Yep, it definitely sounds like you've got a bad indicator.

 

[MChalkley]

John - Re the "a dirty air filter cleans better than a clean one" discussion: I've always thought that sounded like a lot of hooey, too. My question to a Kubota rep who told me that was: "Why would the air filter manufacturers design a filter so it wouldn't be effective right out of the box? If it needed a little dirt on it to make it work, don't you think they'd make it with the dirt in it?" I think he figured I was too dumb to try to explain it to, because he didn't try. /w3tcompact/icons/wink.gif

I'll tell you one thing I do believe, though: I believe you should have a good air filter restriction gauge (meaning one that works) and not take the filter out until it's dirty enough to replace. This is especially true with systems like my Cummins' equipped Dodge, where you have to open the clean-air side, too, to check it. I believe the dirt introduced into the clean-air side is a lot worse than leaving the filter alone until it's dirty enough to show on the restriction gauge. Of course, on the ones like the Kubota, with an inner and an outer, you can change or check the outer with reckless abandon. /w3tcompact/icons/smile.gif

 

[BobinCols]

I was at a Wix-Napa filter class several years ago and the man giving the class told us that as the filter got dirty it was more efficient up to a point, that's why a restriction gauge is helpful when to change the air filter. You can't go by looks alone. I have seen air filters on a Ford powerstroke with less than 10,000 road miles that looked like it had 100,000 miles on it and the restriction gauge showed ok-the filter was replaced because it was so bad. Each person has to do what's right for them and it won't be the same for each of us as we have different work environments and different air filtration systems on our vehicles from different manufacturers. Go to Baldwin filters for more reading material on air filters and dirt: <A target="_blank" HREF=http://www.baldwinfilter.com/lines/air.html>http://www.baldwinfilter.com/lines/air.html</A>

 

[MChalkley]

BobInCols - I think I understand what you're saying. My opinion is that the air filter restriction indicator is quite reliable (again, assuming it's working), unless the air filter has ruptured, in which case it will tell you nothing. So, no matter how bad a filter looks, unless it's ruptured, and therefore offering no restriction to air flow (and no filtering, of course), you're better off to rely on the air filter indicator. Ruptures should be very rare, fortunately.