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Oil usage
- Timothy Barnett
- Posts: 2
- Joined: Thu May 28, 2015 3:46 pm
Re: Oil usage
I noticed you mentioned blow by - may I inquire what you meant by that term?
William Hughes- Posts: 97
- Joined: Mon Apr 21, 2014 9:23 pm
- Location: Saskatoon, SK
Re: Oil usage
Thanks for the help.
- Timothy Barnett
- Posts: 2
- Joined: Thu May 28, 2015 3:46 pm
Re: Oil usage
Keep in mind that there's more oil in the system than what you read on the stick. On the Cirrus we put 7 qts in at the oil change yielding 6 on the dipstick. A quart is taken by the filter, lines and "in suspension" in the engine. If we don't fly for a few weeks more drains down and the reading may go from 6 to 8 on the stick. Run the engine and it's back at 6. On the PA-30 similar situation but since I installed Air Wolf remote filters, which are larger -109 filters instead of stock -108, the system takes up 2 qts beyond the reading on the stick. I put 8qts per side yielding 6 on the stick.
For twin owners always remember that for the same volume of oil in each engine the left engine will show 1/2 - 3/4 qt more on the dipstick due to the stick position on the right side of the engine and the angle of the engines due to the dihedral of the wings. There are other threads on this.
- Charles
Charles Schefer- Posts: 563
- Joined: Mon Mar 12, 2012 7:09 pm
Re: Oil usage
I mean, if it sits for a week the engine will show more oil. If I then fly it on a long weekend for a long trip, say four or five three hour legs, then the oil will drop a quart. If I let it sit for another week, then back up it comes.
That makes all sorts of sense now that you mention that the oil could take a few days to actually all drain right down.
William Hughes- Posts: 97
- Joined: Mon Apr 21, 2014 9:23 pm
- Location: Saskatoon, SK
Re: Oil usage
Charles Schefer- Posts: 563
- Joined: Mon Mar 12, 2012 7:09 pm
Re: Oil usage
Just for your reference the term blow by is usually referred to a condition were your rings in one or more Pistons are not seated tight enough so that oil and heat is blowing by the cylinder walls and is effectively cooking your oil inside the crankcase. While your oil consumption will go up, the most tell tell sign is that your oil will be pitch black after an oil change and within a few hours. I have this problem too, but my engine is over TBO so I just change my oil every 25 hours or so until I'm ready to do the overhaul.
Alan
Alan Cheak- ICS member
- Posts: 142
- Joined: Sun Jan 12, 2003 8:17 pm
- Location: Peachtree City, GA KFFC