TSIO-360LB OIL LEAK

I have the most baffling problem in the history of aviation. In
January, the engine in my Mooney 231 was overhauled by a reputable
shop. Since then, I can not fly at high altitudes (above 15K) without
consuming mass quantities of oil. It appears the oil is coming out
the breather tube.

After spending a month at the Mooney factory we learned the following:

1. They hooked up an airspeed indicator to the oil dipstick tube and
discovered that, at altitude, opening the cowl flaps will reduce the
crankcase pressure by nearly 1/2.

2. It isn't the crankshaft seal (already replaced that).

3. Not the position of the breather tube (Mooney verified it to be
correct) and today our local shop removed the elbow from the end so
that the tube now ends well inside the cowl (ensuring it's not in a
low pressure area). Didn't help at all.

4. Forty minutes at 17K will use in excess of two quarts. Below 15K
there is no visible oil loss.

5. Compressions on all cylnders are between 74/80 and 78/80.

The airplane has both a Merlyn Automatic Wastegate and the Turbo Plus
Intercooler.

Any thoughts??

Thanks,

Steve Conley
N231ML - SAC

(Stephen Conley) wrote in message . com...
I have the most baffling problem in the history of aviation. In
January, the engine in my Mooney 231 was overhauled by a reputable
shop. Since then, I can not fly at high altitudes (above 15K) without
consuming mass quantities of oil. It appears the oil is coming out
the breather tube.

I don't have an answer, but failing everything else, a workaround
would be to purchase and install an air/oil separator. This would at
least confirm if the oil is coming out the breather tube or not.

http://www.m-20turbos.com/breather.htm

-Nathan

(Stephen Conley) wrote in
om:

1. They hooked up an airspeed indicator to the oil dipstick tube and
discovered that, at altitude, opening the cowl flaps will reduce the
crankcase pressure by nearly 1/2.

Yes, but from what to what? Max is 100 (although I think it used to be
90).


-----------------------------------------------
James M. Knox
TriSoft ph 512-385-0316
1109-A Shady Lane fax 512-366-4331
Austin, Tx 78721
-----------------------------------------------

I would be looking at the turbo charger seals and bearings and waste
gate controller.
The higher you go the more the turbo charger has to work which puts
more stress on the seals and bearings due to a larger pressure
difference. Have some one follow you and look for exhaust smoke
above 17K.

On 28 Aug 2003 18:26:55 -0700, (Stephen Conley)
wrote:

I have the most baffling problem in the history of aviation. In
January, the engine in my Mooney 231 was overhauled by a reputable
shop. Since then, I can not fly at high altitudes (above 15K) without
consuming mass quantities of oil. It appears the oil is coming out
the breather tube.

After spending a month at the Mooney factory we learned the following:

1. They hooked up an airspeed indicator to the oil dipstick tube and
discovered that, at altitude, opening the cowl flaps will reduce the
crankcase pressure by nearly 1/2.

2. It isn't the crankshaft seal (already replaced that).

3. Not the position of the breather tube (Mooney verified it to be
correct) and today our local shop removed the elbow from the end so
that the tube now ends well inside the cowl (ensuring it's not in a
low pressure area). Didn't help at all.

4. Forty minutes at 17K will use in excess of two quarts. Below 15K
there is no visible oil loss.

5. Compressions on all cylnders are between 74/80 and 78/80.

The airplane has both a Merlyn Automatic Wastegate and the Turbo Plus
Intercooler.

Any thoughts??

Thanks,

Steve Conley
N231ML - SAC

Stephen Conley wrote:
: I have the most baffling problem in the history of aviation. In
: January, the engine in my Mooney 231 was overhauled by a reputable
: shop. Since then, I can not fly at high altitudes (above 15K) without
: consuming mass quantities of oil. It appears the oil is coming out
: the breather tube.

Do you have a leak from your pressurized mags into the crankcase? If you've
got a leak here, it will pressurize the crankcase more and more as you climb.

Were all the "upper deck" pressure lines hooked up correctly?

Are you sure the oil is coming from the breather tube? You'd have a large
oil mess under the fuselage if you were losing oil that quickly. I would
be more inclined to think the oil is leaking from one of the turbo bearings,
and being burned in the engine or vaporized in the tailpipe.

Please keep us (me) informed, as I am considering a 231 for my next plane.
--
Aaron Coolidge (N9376J)