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Oil use on long cross country


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As some of you know I recently acquired a 66 E model. Sunday I flew it from KOWP to 58M which ended up being two stops and about 8 to 8.5 hours of flight time. Prior to flight I checked the oil and it was at 6 quarts. Yesterday I went to the airport to do some pattern work and checked the oil in preflight and it was just a touch below 4. There was some oil below the air intake and down the underside of the engine cowling.

I'm wondering if this rate is normal for a long cross country, and maybe I had some venting along the way too. Any thoughts?

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50 minutes ago, gitmo234 said:

As some of you know I recently acquired a 66 E model. Sunday I flew it from KOWP to 58M which ended up being two stops and about 8 to 8.5 hours of flight time. Prior to flight I checked the oil and it was at 6 quarts. Yesterday I went to the airport to do some pattern work and checked the oil in preflight and it was just a touch below 4. There was some oil below the air intake and down the underside of the engine cowling.

I'm wondering if this rate is normal for a long cross country, and maybe I had some venting along the way too. Any thoughts?

Check to see what your POH says about oil quantity for extended flight. Starting extended flight with 6 quarts sounds low. I know my POH says 8 qts for extended flight.

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My J will definitely stabilize at 6.5 quarts, but will throw out anything more than that. I also use more oil with long climbs and high RPM, but seeing less than 4 quarts demands a good cleaning and inspection. Not sure where the oil leak is, but valve covers, cylinder drain tube connections, case cracks and front crank seals are common. 

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First stop was 6, but that was after 90 minutes only. The second stop it appeared to be 6 or slightly lower, but it was night, and the oil was so clear/new looking that it was hard to tell and we weren't sitting long enough for the oil to collect again to get an accurate reading. It was a very quick refuel, oil check, and get in the air to try and get back before midnight

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I've been told that if a plane sits a few inches nose high when parked it can influence the dip stick measurement by a full quart...sometimes the ramps we park on are not so level. 

In my F, I fly with 6 and burn about a quart every 4 hours (beginning ~12 hours after the oil change) on long flights, long climbs, high RPM, etc. 

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1 minute ago, Brian Scranton said:

I've been told that if a plane sits a few inches nose high when parked it can influence the dip stick measurement by a full quart...sometimes the ramps we park on are not so level. 

In my F, I fly with 6 and burn about a quart every 4 hours (beginning ~12 hours after the oil change) on long flights, long climbs, high RPM, etc. 

I could definitely see that being a problem. I also have one cylinder with <100 hours on it and one with about 110 hours.

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In my F, I fly with 6 and burn about a quart every 4 hours (beginning ~12 hours after the oil change) on long flights, long climbs, high RPM, etc. 


About the same here, but another 66E. If I fill to 8 qts after an oil change, it blows out or get "used" filling the additional hoses to the relocated oil filter faster. Then settles down around the 6 qt level.
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10 minutes ago, 211º said:

 

 


About the same here, but another 66E. If I fill to 8 qts after an oil change, it blows out or get "used" filling the additional hoses to the relocated oil filter faster. Then settles down around the 6 qt level.

 

This could be part of the case. Oil was changed and it hasn't been run since until I started it up for the cross country

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One unanswered question: how old is your oil? Before 12-15 hours, I don't burn anything of notice. But as the oil gets dirty (or breakdown--which doesn't really happen) I begin to use more (like I said, about a qt per 4-6 hours). 

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4 hours ago, Brian Scranton said:

One unanswered question: how old is your oil? Before 12-15 hours, I don't burn anything of notice. But as the oil gets dirty (or breakdown--which doesn't really happen) I begin to use more (like I said, about a qt per 4-6 hours). 

Oil was changed in April and not flown so ~0 hrs...however, I completely agree that oil usage goes up as the hrs increase 0-25 vs 25+. 

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46 minutes ago, Godfather said:

Oil was changed in April and not flown so ~0 hrs...however, I completely agree that oil usage goes up as the hrs increase 0-25 vs 25+. 

When I change oil, I put on a new filter and add 7 qts., then take a test flight and check for leaks. It will read just above 6 for a few hours, and generally takes 10-12 hours before I add the first quart (but I may add 1/2 qt before a long trip). Long climbs to altitude and cruising at 2500 does increase oil usage above short, low burger runs at 2300 . . . .

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2 hours ago, Yetti said:

Run it. Watch it. I dont think you have enough history with the engine.   See the thread about 2500 on climb out

I’m thinking this is the answer for now. i can’t find the thread you mentioned.  Next week I’m due to start making my commute to DC by air when VFR. I’ll whipe it down and observe

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Guest paulie

Every engine has it's own level. People fill up to eight and think it's burning oil. Let it run down to 5, fly it and see if it stabilizes at that level. If so fill to six and repeat. If stable try seven. My io-360 likes to be at 6.5, any more and it blows it out the breather.

 

 

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Summary:

1) measuring the oil level takes being level. Done after sitting a day...

1a) oil hides in the oil cooler, and prop, and other places...

2) over 6qts, high probability of being pushed out the case vent.

3) high power, for a long climb, and high angle of climb aids the oil pushing out the vent.

4) oil that gets burned leaves a trail in the exhaust pipe.

5) oil that gets vented leaves a trail on the belly.

6) There is a list of rubber bits that can be checked for leaks.

7) rubber bit leaks leave a trail all over the inside of the cowl.

8) case cracks leak oil.  Something that gets looked into after Steps 1 - 7 have been exhausted...

9) Long cruise itself doesn't use up much oil as discussed. It lacks the characteristics of high power, high angle, and high temperature (CHT and oilT)

10) Do a lot of measuring to get to know your plane.

Best regards,

-a-

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23 minutes ago, gitmo234 said:

I’m thinking this is the answer for now. i can’t find the thread you mentioned.  Next week I’m due to start making my commute to DC by air when VFR. I’ll whipe it down and observe

Here it is.

 

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8 hours ago, carusoam said:

Summary:

1) measuring the oil level takes being level. Done after sitting a day...

1a) oil hides in the oil cooler, and prop, and other places...

2) over 6qts, high probability of being pushed out the case vent.

3) high power, for a long climb, and high angle of climb aids the oil pushing out the vent.

4) oil that gets burned leaves a trail in the exhaust pipe.

5) oil that gets vented leaves a trail on the belly.

6) There is a list of rubber bits that can be checked for leaks.

7) rubber bit leaks leave a trail all over the inside of the cowl.

8) case cracks leak oil.  Something that gets looked into after Steps 1 - 7 have been exhausted...

9) Long cruise itself doesn't use up much oil as discussed. It lacks the characteristics of high power, high angle, and high temperature (CHT and oilT)

10) Do a lot of measuring to get to know your plane.

Best regards,

-a-

Great, thanks. Lots to look at. This could be a combo of a lot. New oil change after sitting awhile + not being run after and sitting awhile + not being level + high angle of attack.

We were climbing out at 25/2500 so lower setting but at 110 mph IAS I was getting about 1k feet per minute sometimes.

My plan is to wipe it down, run it some more, take it easy on climb AOA, check it a while and develop the actual "pattern of life" or "pattern of oil" before I get too worried. For good measure I may remove a cowling just to make sure it doesn't look like an engine murder scene.

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Huge benefit of having the side cheeks that come off the cowling...

1) each cylinder head has an oil return line with so many aged hose clamps...

2) each rocker box cover has a gasket that was once cork...

3) airspeed has a tendency to really move an oil drip around... including out the front of the cowl.

Fun stuff...

Best regards,

-a-

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