ADC Oil Screen

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ADC Oil Screen

Postby IP076 » Mon Jul 13, 2020 5:12 am


I'm trying to do some research in preparation for the first oil change for me.

The airplane has an ADC Oil Filter installed per STC SA4172NM.

Disclaimer, the airplane and the books are 1800 miles away from me at the moment.

I've been googling around and trying to see what I can find as far as documentation, which turns out to be not much. Does anyone else have this equipment on their 170 and may provide some guidance to a newbie? From what I understand this is a reusable/cleanable screen instead of the typical single use filter. Is the original screen still remain in place? Any particular parts that one should have on hand for an oil change specific to the ADC system?

The airplane was picked up with a fresh oil change by a good friend of mine. Between getting it to his house, me flying for my insurance check out, some recreational flying planned, and letting my friend fly it a couple of times for storing it until I could make it out there, the airplane will be close to 20 hours on the existing oil. I'll have a 15-20 hour journey home, so we're planning on knocking out an oil change before I head west.

Thanks for any info you can provide.
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Re: ADC Oil Screen

Postby GAHorn » Mon Jul 13, 2020 5:26 pm

According to a 1999 AOPA report on oil filtration: In addition to its filter adapters using conventional spin-on elements, ADC sells a unique disk-style filter made up of woven stainless-steel cloth. It's said to provide 25-micron absolute filtration. The filter is held in a clamshell enclosure and protected by a ball-and-spring bypass valve. And here's the key element of the ADC setup — when the bypass valve opens, a lamp installed on the instrument panel lights. This way, the pilot knows when the filter goes into bypass and can make arrangements to look at the element. ADC acknowledges that its filter has much less media area than conventional filters, but says this is central to the design. You don't want the filter to be full of a lot of metal before you find out about it; with the ADC element, an abnormal amount of engine detritus will clog the element and open the bypass sooner than normal. ADC also says that its filter can benefit oil cooling thanks to the heat-sink-like fin arrangement. This is likely to be true, but you'll need to make sure the filter is in an area of good air flow to maximize this effect. Finally, in testing against conventional filters, the ADC disk fared poorly in the particle-entrapment tests. ADC counters that the tests measure the performance of the filters in new condition and that the ADC disk actually increases its filtration as it accumulates muck. True of paper-media filters as well, this characteristic is more pronounced in the ADC arrangement.

It’s also interesting that Air Wolf (producer of the ADC system) developed a replacement SPIN ON system for their previous “screen” system and offered a $50 trade-in for those who replaced the screen system. ... r-systems/

Hope this helps.
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Re: ADC Oil Screen

Postby IP076 » Mon Jul 13, 2020 6:58 pm

Thank you!

It definitely seems difficult to come across any technical docs for the version I have. I did notice the rebate offer a while back and it made me think that even they didn't think this system was the best idea.

At the moment, I'm just trying to make sure I get an understanding of the mod for the first oil change. Specifically, I'm trying to find out if there's a filter I need to have on hand to replace.

Someone mentioned in another thread, I'll use this until I have a problem with it but then likely go to one of the spin on oil filter arrangements.

Thanks again.
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Re: ADC Oil Screen

Postby hilltop170 » Mon Jul 13, 2020 7:17 pm

My understanding is you remove the filter element and wash it in solvent and reinstall it. Of course, that only applies if the element is in good shape.

Jeff Pearson at 818-371-9848 is a real proponent of the ADC and very knowledgeable about them. Give him a call. He may even have some spare elements.
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1951 170A, N1715D, s/n 20158, O-300D
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Bought again in 2006 after 22 years.
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