Air Filter Observations (1 Viewer)

[Tools R Us]

I have done the off road game for a long time, mostly in the desert, some off road racing, etc. Have fallen for the air filter advertizing/myths/BS, a new filter is best, change them often, etc. A few years ago a buddy who works for the biggest local heavy equipment shop, started an argument about air filters, turns out he had the facts. An engineer from one of the air filter manufactures (IIRC Donaldson) had just put on a seminar on how to get the most from your air filter. The next time he was in, brought the handouts, titled something like; Changing the air filter is the best way to wreck your motor. The seminar points:

1: Most damaging debris gets into the motor during filter service, do it as little as possible. Be very careful to fully clean the housing, gaskets, etc, when doing filter service.

2: The second highest damaging debris contribution is from the first part of a new or cleaned filter life. New or cleaned filters are least efficient, they get more efficient with debris loading and are most efficient just before they are too loaded, cause power loss.

3: Inspecting a filter is almost unless. It can look dirty, it should, that’s it job, but maybe fully functional, efficient. The only way to tell if a filter is fully loaded is by measuring restriction, inspecting will only cause wear to the seals, likely get debris on the clean side of the filter, etc.

4: They never recommend cleaning a filter. But if you do, never get cleaning solution from the outside of the filter to the inside. Only blow, rinse, etc, from the inside out. Be very gentle when cleaning, high pressures can easily damage, rearrange filter fibers, cause holes, etc, especially when the filter is wet.

5: The only way to truly maintain filters is with a restriction gauge. Properly used, will increase life of filter, motor, etc, reduce all related maintenance costs. Properly bolt it together, seal it up and don’t touch it until the gauge indicates it is time.

 

[Tools R Us]

For someone who always cleaned filters, often, this was a bit of a tough pill. Installed a FilterMinder, went a couple of years, couldn’t take the gauge not moving, the filter in the rig had been cleaned several times, etc. So, as part of the Cruise Moab prep in April 2010, installed a new cleanable filter, sealed it up and left it.

This fall the gauge started moving, had a couple of trips planned that included lots of up hill, so deemed it time. The run was over to 30K miles, by my documentation 116 trail days, likely more, those days are from photo and/or track logs, do lots of Forest Service work, sometimes don’t take pix or save a log. Lots of them very dusty desert conditions. The last couple of Utah trips have been very dry, so places like Beef Basin, Lockhart, White Rim, (most run 4 times on this filter) etc, were silt clouds, with my rig often tail gunning.

The FilterMinder read ~18in/h2o, could likely of gone further, but was dying to look! Was surprised at what was found. Almost no debris in the housing, only a bit in the textures of the can base. Cant see it in the pic, but the filter pleats are ~1/2 full of silt. The next pic is simply taping it on the floor, actually dropped it ~1". It was significantly/noticeably heaver than the cleaned one. When handled silt falls out everywhere.

Conclusion: Totally sold on the FilterMinder, all of my rigs will have one. The ‘80 series filter setup is killer, the cyclonic works great, as long as the tuna can is emptied/cleaned, the filter will last a very longtime. In less dusty conditions, I bet they would go 50K or even 100K miles, making the cleanable filter a lifetime unit? They are very efficient/effective units and most likely clean them way too often.

 

[Finnyfam60]

Nice writeup and info!

I motion for FAQ.

 

[jhunhapi]

where did you exactly put them? tnks for the info

 

[Copenhagen1]

where did you exactly put them? tnks for the info

X2

And great write up x2 as well. Very interesting information.

Sent from my iPhone using IH8MUD

 

[tominboise]

Right on. I am going to buy and install one of these in my LX and in my diesel Silverado.

Did you just drill a hole in your filter housing to mount it?

 

[oilbrnr]

So, did you clean and re-use that filter, or put in a new one? Assuming you followed point 4 and put in a new one...

I've had Filter Minders that came from the factory on my diesel trucks, and only recall once that I saw one move. I really started to doubt their functionality. Guess I'll let the filter in the Dmax go longer this time and see what happens.

 

[scrowley]

Nice write up. Holy s*** that is the most dirty filter I have ever seen.

 

[Howard705]

Hmmm... lots of gas chevy trucks in the '90 had them. I always pushed the resets on them to see if they were starting to move. Always figured there was a good reason for them. Great info!

 

[mudbludger]

Its mounted just under the seam of the outlet pipe for the air filter housing, judging by its position I would assume a hole has been drilled for its fitment. Looks like a good idea, will have to get one as I am guilty of changing an air filter element every 5k

Thanks for the heads up.

 

[jcardona1]

Nice write up! I'm interested. Did you simply thread this into the intake pipe? Or is there a nut on the inside? I see they sell two version of this, threaded and one with a grommet...

 

[canman]

Good info. I'm always worried about dirt etc getting into the engine when I'm changing either the oil, oil filter and air filter. Reducing frequency of these maintenance actions certainly reduces the chances of introducing stuff into the engine. I will likely install one of those gage's now for s$$ts and giggles.

 

[94SRUNNER]

Kevin as always, thank you for the great knowledge you provide so many of us with.

I will also be adding this to my to-do list for the upcoming week of projects.

 

[Paul_L]

http://www.consumerreports.org/cro/magazine/2012/08/debunking-fuel-economy-myths/index.htm

 

[canman]

More info on this from Donaldson. Interesting that they recommend against any type of cleaning for their heavy duty type filters...Begs the question if one should wash the OEM Toyoa filter or just replace based on either filter minder reading or age.

http://www.donaldson.com/en/engine/support/datalibrary/073635.pdf


http://youtu.be/vUtkeRXeCoc

 

[Tools R Us]

This is the one that I have: http://www.amazon.com/Wix-24800-Air-Filter-Monitor/dp/B000CSGT7S/ref=pd_sim_sbs_auto_4 Not Wix brand, but the same thing. It didn't come with a grommet. Has a brass fitting that screws into the gauge, IIRC, 3/8" x 24 thread. Got a short bolt that fit, drilled a small hole through it for airflow. Installed it with loc-tite, wouldn't want it to fall out!

It can be installed anywhere between the filter and throttle butterfly. I put it in a flat spot where I could get a wrench to the bolt.

 

[Tools R Us]

There are a ton of differing types, rhyary installed an electronic one in his rig: https://forum.ih8mud.com/80-series-tech/423040-adding-electronic-filterminder-your-rig.html

I don't see the point. The way the under hood units work: When the motor is run, it registers the reading, they ratchet, hold the highest reading, push the button to reset. The only time that it "sees" big readings is at full throttle/RPM. Even with the filter in the condition that it was, could have reset and if just cruising around town, it would have shown a relatively low reading. The movement to higher readings is glacial, mine shows ~8in/h2o on a fresh filter, went years that way, reset, came back the same, repeat. Simply glancing at it (optionally resetting) when you are under the hood is fine.

Some of them (like K&N) only have a couple of steps, good and clean. I wanted one with more steps, so I could watch the progression. There are two "rules of thumb", one says that on gas motors the filter clean number is ~20-25in/h2o, the other says clean when the restriction reaches ~10in/h2o higher than the clean filter reading. That is why I changed at ~18in/h2o, don't know that it would make any difference if it was run to 25in/h2o?

This one looks good, lots of steps, grommet type, pop a hole and stick it in. http://www.amazon.com/Wix-24801-Air-Filter-Monitor/dp/B0014BI1KA

 

[Tools R Us]

So, did you clean and re-use that filter, or put in a new one? Assuming you followed point 4 and put in a new one...

I have two of the cleanable type, had one clean on the shelf, so tossed it in, will see how long that one goes.

I've had Filter Minders that came from the factory on my diesel trucks, and only recall once that I saw one move. I really started to doubt their functionality. Guess I'll let the filter in the Dmax go longer this time and see what happens.

If the filter setup is well designed, it will take a very longtime. It really highlights how much resource most waste on them!

 

[Tapage]

here is where I have mine ... I did along with my last turbo intercooler mod and the bad news is my air box / filter ( OEM ) it's way too restrictive for my turbo ( booster 24 PSI ) setup ..

 

[BILT4ME]

I agree with all of the statements by Tools R Us. Having worked on the farm and in very heavy dust and dirty conditions, I have seen air filters nearly completely full and plugged. I have worked in the industrial air filtration industry for over 25 years and the theories work the same in regard to filtration and what is referred to as the "dust cake".

Filtration does, indeed, get better the dirtier a filter becomes. One of the key reasons people change their filters often is not because of better filtration, but because they are told they will get better gas mileage by having a cleaner filter. This, too is true. As differential pressure (DP) increases, the resistance to airflow increases and it requires more horsepower to draw the air through the filter. Since the engines are basically a positive displacement pump, it has to work to suck the air through. Pushing a filter to the 20" WC (water column) is definitely getting very dirty. Pushing a filter to 30" creates a LOT of resistance. I am sure someone has actually run the HP required from a dyno for clean filters VS dirty air filters. The differences can be simulated (not actually using a clean or dirty filter) on a dyno if anyone is interested and has a dyno at their disposal.

Knowing the Toyota LC group, everyone is more about longevity and the heck with gas mileage (to some degree). If you are more about squeezing the most HP and gas mileage and less concerned with getting 500K miles out of your truck, you may want to change the filter more often. That's for those that like to tweak the last 0.10 MPG out of the LC.

Either way you like, use your truck the way best suits you. If you're going to be out in the dust and dirt, don't change your filter until it's time. If all you do is drive in the city and never see the dirt, change your filter all you want, your filter dealer will love you.

By the way, you can also set up a gauge inside the cab to watch your DP on your filter if you like. (It's kinda gaudy though) Yes, as the throttle opens, the DP increases because you are pulling more air through the tube, increasing the velocity, which translates to higher resistance (DP).