My O-320 has 65 hours on it since major overhaul. I have put 20 hours on the engine since I bought the plane and I am "making" oil. The break-in oil was changed to Phillips X/C 20W-50 at 46 hours. In my 20 hours of flying the oil level has increased by 1 - 1 1/2 quarts. I can only surmise that gas is getting into the oil somehow. Has anyone experienced this problem? The majority of the last 20 hours has been low power, in the pattern work. Do I have a serious engine problem?
Engine making oil
- Thread starter grandpa
- Start date
behindpropellers
Registered User
NE Ohio
grandpa said:
Dumb question....gotta start somewhere.
You did check the oil when the engine was cold?
Level Ground?
Dipstick screwed all of the way in?
Did anybody put in extra oil?
Does the oil smell like gas? Has it lost its viscosity (runny)?
46 hours on breakin oil is a lot.
Maybe you can ship me the spare oil it makes....because mine just leaks it out
Tim
Roger Peterson
Registered User
Sweeny, Texas
your oil analysis will tell you how much gas you have in the oil. Also the stick must be wiped clean before each oil ck as the oil will usually crawl up the stick at least by one qt while sitting. You should make a oil leak some where as all engines should leak some or you won't be able to tell when they are out of oil.
mike mcs repair
Registered User
chugiak AK
couple questions....
did you read dipstick when you put X number of quarts in to make sure its reads right/right dipstick with engine?
oil milky looking when hot? (water/condensation)
oil Bubbly when hot (air in oil, missing internal plug in oil galley/spun bearing)
check the screen/filter NOW since you are seeing something funny???
did you read dipstick when you put X number of quarts in to make sure its reads right/right dipstick with engine?
oil milky looking when hot? (water/condensation)
oil Bubbly when hot (air in oil, missing internal plug in oil galley/spun bearing)
check the screen/filter NOW since you are seeing something funny???
mike mcs repair
Registered User
chugiak AK
dipstick marked for floats and now on wheels/skis, or vise-versa....
Calvin Brandt
Registered User
Delano, Mn
99% Certain gas is getting in your oil. I had this problem with a generator at one time. Drain the oil and add new oil and watch it. I suspect the rings on one cylinder is the culpert. Problem may go away after the second oil change. If not add some Marvel Mystery oil in the oil and gas per recommendations or do it now. Its good stuff.
behindpropellers
Registered User
NE Ohio
Calvin Brandt said:
Should he run it like he stole it or baby it?
irishfield
Registered User
Penetanguishene, Ontario Canada
Lance said:
Yep... what Lance said.. I can't see it getting in there any other way. Updraft carb would pour gas on the floor...not like a portable generator with the tank above.. and side draft carb. I had my Honda hydraulic from sitting for a few months with the fuel valve open.
S
StewartB
New owner? I'd start over with a new oil change and a quick run-in flight. Then I'd scribe the dipstick to represent a known oil quantity. I expect factory markings to be wrong until proven correct. I haven't had a correct one yet.
Stewart
Stewart
mike mcs repair
Registered User
chugiak AK
irishfield said:
vote 3 for lance, never thought of that.... but,but,but on second thought... how will the gas get from the primers into the intakes, through an open valve, then into the cyl and then into the crankcase ...without making a huge mess on the floor back down the intakes and out the carb air box????? don't think it would flow into there...
Calvin Brandt
Registered User
Delano, Mn
behindpropellers said:
Run it like you stole it.
irishfield
Registered User
Penetanguishene, Ontario Canada
mike mcs repair said:
Maybe he parks on a heavy slant and it only makes it to the cylinder! lol
Calvin Brandt
Registered User
Delano, Mn
If you have a leaking pimer the carb will be overflowing and leaking on the floor and not into the crank case.
Dave Prizio
Registered User
Tustin, CA
Making Oil
Since the primer lines go into the intake ports upstream of the valves, it seems that a leaking primer would dump all of at least most of he fuel back into the intake tract and down to the carburetor, not into the cylinders. I would suspect an internal leak in the fuel pump. I think a leak in the fuel pump diaphram may allow fuel to go right into the crankcase, but I must admit that I have never had one of those fuel pumps apart.
Since the primer lines go into the intake ports upstream of the valves, it seems that a leaking primer would dump all of at least most of he fuel back into the intake tract and down to the carburetor, not into the cylinders. I would suspect an internal leak in the fuel pump. I think a leak in the fuel pump diaphram may allow fuel to go right into the crankcase, but I must admit that I have never had one of those fuel pumps apart.
I appreciate all the responses, and no question's too dumb because I'm pretty new to aircraft engines. I was vague about engine break-in; the engine had two oil changes during break-in and the third change was to dispersant oil at 46 hours. The oil has never appeared milky so I doubted water contamination. However, I've since learned that water can be entrained in the oil to a small degree and not cloud the color. But my quantity increase (1 qt.) is beyond that scenario. So I have drained the oil and I captured nearly 9 qts. The oil was thin but not runny (@ 30 deg. F). I could not detect a gas odor in the oil which I assumed would be quite strong if it accounts for the extra quantity I drained. But I cannot eliminate that possibility yet. I checked the dipstick carefully with each new additional quart of oil I added. The readings were consistently 1/2 to 3/4 quart low. I added 7 quarts and the dipstick shows approximately 6 1/2. This is consistent with the level reading when I purchased the airplane. I've only flown 1 hour since the oil change and the oil looks perfect and the level cold is unchanged at 6 1/2. I don't expect to see much change until I get 5-10 more hours on it. I had taped off the oil cooler when I was flying in 8-10 deg. F weather in order to keep the temp near 180. Pressure at high idle was good @ 78-80 psi. On the last flight with the OAT @ 30 deg F I taped only half the cooler and oil temp was 160 and pressure 80, which I consider good or normal. I will let you all know how this works out. Again, I appreciate everyone's help.
