Oil consumption

[ScottM]

I have an O320-D3G and I have recently just done a top overhaul for reasons in another thread. But it was to comply with the ECI AD.

My mechanic said that we need to watch the oil consumption through break in. I have added my first quart of oil since the oil change after the top. It happened at 13 Tach hours. What is normal consumption??

 

[tonycondon]

sounds about right scott. mechanics at my FBO always said when it got to 1 qt every 5 hrs or less, you were looking at needing an overhaul.

 

[mikea]

sounds about right scott. mechanics at my FBO always said when it got to 1 qt every 5 hrs or less, you were looking at needing an overhaul.

Lycoming says the limit is 1qt every 2 hours for my O-540. I was adding 1 every 2-3 hours before I got my top OH. It used a quart or two in the first 8 hours early last season but it's been using hardly enough to measure since.

I had the M20 oil/air separator installed at the OH which probably throws all oil consumption measurements off. I'm good at fixing my problems at least twice.

 

[JRitt]

Thats about what I am using on my fresh O/H on an O320-H2AD (23hrs 1.5 qts). First oil change is this weekend.

 

[Stache]

Every engine will have a different oil burn during break in. This is because the rings have to be sized to the piston and when the mechanic files off a small amount to get the proper rig gap they might shave off too much or maybe not enough. The rings are pushed out by the compression gasses to seat against the cylinder walls and will wear in. This wearing in will cause oil burn or blow by until the cylinder walls are worn to the rings.

If the cylinders are not using or burning any oil something is wrong after an overhaul or repair. All cylinders should use oil for about the first 50 hours or so. The manufacture oil consumption is only a recommendation on a test engine they used during certification under control factors.

I would suggest watching the oil burn and oil pressure. When you change oil have the mechanic cut open the filter and look for metal, you will see some. Over time the amount of metal will go away (its normal). All aircraft engine should use a little oil again its normal and designed to do so.

Stache

 

[Ed Guthrie]

sounds about right scott. mechanics at my FBO always said when it got to 1 qt every 5 hrs or less, you were looking at needing an overhaul.

That answer depends on the engine. I'd love to have my oil consumption be as little as 1 qt every 5 hours. For example, I've never seen oil consumption less 1 qt/5 hours with the IO-360-A1B6D I fly, and that's experience from the point 1000 hours since factory new through the next ~1200 hours, an overhaul, and 1300 hours more.

 

[pete177]

ya know ed, on my E I was using a quart every 5 hours and found quite a bit of it on the belly with no other oil burn symptons. It was almost like the oil was being sucked out of the breather. The little hole anti-sucetion/freeze over hole thats in the breather fitting seemed pretty small compared to some other motors so I enlarged it some. Wont know if it's made any difference for a bit as the plane's in for paint/interior.

 

[EdFred]

I know with my O-360-A3A, anything over 5-1/2-6 quarts just blows right out. Then takes about 10 hours to get down below 5. So, I keep my oil level between 4 and 6 quarts. No temp issues, no pressure issues.

 

[Tom-D]

If the cylinders are not using or burning any oil something is wrong after an overhaul or repair. All cylinders should use oil for about the first 50 hours or so.

That thinking is about 20 years out of date..

The new after market cylinders by ECI and Superior, brake in and seal up very quickly.

I have several engines overhauled using after market cylinders that used 1 qt in 25 hours to the first oil change, and under a qt between each oil change after that.

 

[PoAdeleted5]

deleted.