Tempest spin-on oil filter adapter

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Re: Tempest spin-on oil filter adapter

Post by 8258 » Sat May 18, 2019 3:12 am

thanks all for posts on advice - if I can say first of all, without adding your name to your reply and with only the membership number at the top of your messages, I don't know who to thank !

I have considered all of the above. I am very happy to oil change every 25 hours, my concern is the continual disturbance of the delicate oil temperature probe - this is how and why this entire episode began.

I have thought about very close clearance and the fact that the adapted and engine will be 'as one' but at engine vibration might cause the adapter to occasionally fret against the engine mount.

I think I will go head and purchase the mount and use thinner nuts and a thin shaped shim/spacer (with gasket each side) and hope that fits.

thanks
Graham

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Re: Tempest spin-on oil filter adapter

Post by 6298 » Sat May 18, 2019 8:56 pm

8258 wrote:
Sat May 18, 2019 3:12 am
thanks all for posts on advice - if I can say first of all, without adding your name to your reply and with only the membership number at the top of your messages, I don't know who to thank !

I have considered all of the above. I am very happy to oil change every 25 hours, my concern is the continual disturbance of the delicate oil temperature probe - this is how and why this entire episode began.

thanks
Graham
I’m not sure I understand. Does the “delicate oil temperature probe” suffer less damage with a filter than a screen?
Randy Thompson A&P IA Pilot
Hold STC SA547EA for installation of O-200 engine in Cessna 120/140 and 140A"s
Overhaul small Continentals

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Re: Tempest spin-on oil filter adapter

Post by 8258 » Sun May 19, 2019 11:36 am

Once a spin on oil filter is fitted, the delicate temperature probe remains un-touched, as the oil screen (in which the delicate oil temperature probe is fitted) does not need to be removed every 25 hours.

So, no removing of the screen = no removing of the delicate oil temperature probe

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Re: Tempest spin-on oil filter adapter

Post by 2066 » Sun May 19, 2019 1:23 pm

8258 wrote:
Sun May 19, 2019 11:36 am
Once a spin on oil filter is fitted, the delicate temperature probe remains un-touched, as the oil screen (in which the delicate oil temperature probe is fitted) does not need to be removed every 25 hours.

So, no removing of the screen = no removing of the delicate oil temperature probe
As John C. reminds us from time to time, it's important to know that the STC "requires" removal (de-soldering) of the screen. There may be some out there who misinterpreted this as "optional" early on and the danger is that debris may be building up in the now never-looked-at screens, likely leading to eventual engine damage. Mac

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Re: Tempest spin-on oil filter adapter

Post by 6298 » Sun May 19, 2019 6:56 pm

Here is my take on removing the screen. The instructions on the TAF filter say “Use filter with internal by-pass”. When this by-pass is open, contaminates go right past it and into the engine. If the screen was left in place those harmful contaminates would be stopped by the screen.
I have overhauled many C-85’s, C-90’s and O-200’s. The least worn ones have been ones with a screen only and 25 hour consistent oil changes. Most of the ones with filters were ran 60 or more hours between oil changes to reduce the costs of oil and filter replacement. Those engines had much more deterioration that the screened only ones.
I understand the thought that removing the temperature probe every 25 hours could lead to damage, but, replacing the temperature probe is not a common event.
My engine has reached 1800 hours three times and is ready for its next overhaul. Screen only and 25 hour oil changes. One exception was when we flew to Kansas and back for 32 hours.
Randy Thompson A&P IA Pilot
Hold STC SA547EA for installation of O-200 engine in Cessna 120/140 and 140A"s
Overhaul small Continentals

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Re: Tempest spin-on oil filter adapter

Post by 6643 » Sun May 19, 2019 7:51 pm

Here's my take on removing the screen. The STC requires it. If you install the filter adapter and don't remove the screen, you plane is unairworthy.

I have consulted with a prominent engineer who makes a living consulting on engine failure analysis. (He was involved in the Mobile 1 aircraft oil hoopla a while back.) He has assured me that the oil filter will never go into bypass mode under normal circumstances. All aircraft engines with oil filters either have a bypass built into the filter mount, or require a filter with a built in bypass. The TAF setup is no different; there is no bypass built into the adapter so one is required in the filter. The bypass is there in case the filter becomes clogged with retentate to the point where the engine would otherwise be starved for oil. Instead, the filter bypass opens and the engine receives unfiltered oil: better than none. Two points: first, if your filter is clogged with something, you've probably got other problems, and second, the screen is also designed to collapse under the same conditions that would cause the filter to go into bypass, and go into permanent bypass.

The reason the screen must be removed when the filter is installed is to prevent those servicing the filter in the future from assuming it has been removed and ignoring it. The screen can then catch debris that would ordinarily show up in the filter inspection and hide impending doom. Of course, if doom is impending, the screen will eventually go into bypass and dump its contents into the filter all at once.

I have no doubt that Randy's information is correct, but I don't think the filter is the problem. Maybe it's the frequency of oil changes, or maybe it's something else in the maintenance schedule. One thing I am certain of is the filtered oil will have much smaller contaminants than the oil that only sees the screen, and that, by itself, can't be a bad thing.

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Re: Tempest spin-on oil filter adapter

Post by 6643 » Sun May 19, 2019 8:05 pm

Oh, about the idea that removing the screen is (was) optional... Many years ago the then owner of the STC entered into an exclusive marketing agreement with a then well known parts vendor. The vendor took it upon themselves to modify the instructions to indicate removing the screen was optional, but these instructions were never approved by the STC holder or the FAA.

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Re: Tempest spin-on oil filter adapter

Post by V529 » Tue May 21, 2019 8:40 pm

Graham,

If you are still in need of pictures with the oil filter adapter installed with the additional 0-200 mount tube installed I can provide them. I have an 0-200 on my aircraft with the additional "bent tube" on the engine mount. The TAF filter housing fits easily.

The only thing I cannot determine from looking at your pictures is if your "bent tube" is the same as mine? My engine mount came from DUFF aircraft when they still existed.........

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