Tom3holer
MEMBER
Cape Cod
I have a 520 in my 185 that spits oil out the breather all the time.
I thought it might be a function of too much oil but recently, to check the dipstick accuracy, we drained it along with a new filter added 10 qts and it read 9 1/2 on the stick. After 10 hours or so its down almost a 1 Qt . with oil stains down the belly. I would clean it off after each 2 hr flight and had new stains extending back 2 -3 feet.
The engine has 220 hrs on it now since FREM in 2009. I have flown it about 100hrs this past year. The compressions were, from after the first 25 hours when it was switched from mineral to AS 15-50, all in the low 70's with a couple at 70/80. I would think if it was broken in properly the compressions would be better than this.
Pressurizing the crankcase is the reason for dumping oil out the breather as far as I know. One recommendation was to change to mineral oil and run the "piss" out of it for ten hours which might get the rings to seat better and reduce the crankcase pressurization. I would think that with the walls all glazed over that might not be too effective without running a ball hone through each jug.
As always any thoughts or suggestions greatly appreciated.
Tom
I thought it might be a function of too much oil but recently, to check the dipstick accuracy, we drained it along with a new filter added 10 qts and it read 9 1/2 on the stick. After 10 hours or so its down almost a 1 Qt . with oil stains down the belly. I would clean it off after each 2 hr flight and had new stains extending back 2 -3 feet.
The engine has 220 hrs on it now since FREM in 2009. I have flown it about 100hrs this past year. The compressions were, from after the first 25 hours when it was switched from mineral to AS 15-50, all in the low 70's with a couple at 70/80. I would think if it was broken in properly the compressions would be better than this.
Pressurizing the crankcase is the reason for dumping oil out the breather as far as I know. One recommendation was to change to mineral oil and run the "piss" out of it for ten hours which might get the rings to seat better and reduce the crankcase pressurization. I would think that with the walls all glazed over that might not be too effective without running a ball hone through each jug.
As always any thoughts or suggestions greatly appreciated.
Tom