Oil Change Interval

How to keep the Cessna 170 flying and airworthy.

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Mark A
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Joined: Mon Sep 23, 2019 5:44 pm

Oil Change Interval

Post by Mark A »

What’s the recommended oil change interval for the C-145? I was going to change at 25 hours but some folks say that the oil is better now and they change at 50 hours. Thanks
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IA DPE
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Re: Oil Change Interval

Post by IA DPE »

Do you have a Spin On Oil Filer (F&M etc.) or just a screen?

I have the spin on and change at 40- 50 hrs. If I only had a screen, I’d change at 25.
1955 C170B N2993D s/n 26936
1986 DG-400 N9966C
bugs1961
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Re: Oil Change Interval

Post by bugs1961 »

25 recommended with the original screens and up to 50 with an oil filter adapter. Me personally, and with me doing my own oil changes, I shoot for 20 hr changes with the screens. Never let it get to 25.

Good time to clean and gap plugs, take a look at valves with the borescope, inspect exhaust, and take a close look at everything.
Mark A
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Re: Oil Change Interval

Post by Mark A »

I have spin on oil filter. Plugs were cleaned and gapped during annual. Thanks
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dstates
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Re: Oil Change Interval

Post by dstates »

Mark A wrote:I have spin on oil filter. Plugs were cleaned and gapped during annual. Thanks
Always best to go by manufacturer's recommendations...

In general I've always heard oil change at 25 hours for oil screen and 50 hours for spin on filter.
N1235D - 1951 170A - SN: 20118
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GAHorn
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Re: Oil Change Interval

Post by GAHorn »

I’m sure there’s a Continental SB or SL addressing this issue. As already mentioned, originally engines with oil screens were recommended at 25 hours, largely because screens have NO BYPASS capability. When carbon blocks them up then lubrication suffers. (I once helped a friend with his GO-300 on a different matter and it came to my attention he had no knowlege of the screen at all. He had performed his own oil changes fo the last 5 or 6 periods without addressing the screen. When we pulled the screen it was almost completely blocked with carbon.)

Continental published a brochure “Tips on Engine Care” which states the following:
Change engine oil as follows:
• Engines utilizing only an oil screen - Every 25 hours
• Engines that use 4.80 high oil filters - Every 50 hours or 6 months, whichever occurs first.
• Engines that use 5.80 high filters - Every 100 hours.


More important than hours flown is likely the chronological time between oil changes. SIX MONTHS according to Continental, regardless of time flown.
ContinentalEngineCare.pdf
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'53 B-model N146YS SN:25713
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Mark A
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Re: Oil Change Interval

Post by Mark A »

Thanks
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mit
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Re: Oil Change Interval

Post by mit »

Spring and Fall in interior Alaska. Unless you are flying 100 hours a month.
Tim
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