I have a 912 ULS3 3 blade MT propeller
(Version 3 for "Constant Speed" propellers, with drive for hydraulic governor and cover for sealing of governor flange)
When changing the oil lines must be vented so that there is air in the oil system.
With regular 912 ULS is not a problem. The compressed air and rotating propeller around to a steady stream out of oil without air.
But with ULS3 this is a problem. I can stand for 20-30 minutes and turn around the propeller (with compressed air in the tank) without a steady stream of oil. The oil that comes out contains air.
One way is to remove a temp plug on each of the cylinders, I can then crank the propeller fast enough around to a steady stream of oil out.
But according Heavy manual you should not not remove a temp plug from each sylynder. Because then disappear compression. It shall be compression when bleeding the air from the oil system.
In Sweden there are 5-6 new 912 ULS3 engines with MT propellers (hydraulic governor) who have had problems. The problem disappeared when changing the hydraulic tappets. This suggests that the engines have not been properly vented of air in the oil system of the aircraft manufacturer.
Can anyone tell me practice how bleeding the oil on a 912 uls3?
(Version 3 for "Constant Speed" propellers, with drive for hydraulic governor and cover for sealing of governor flange)
When changing the oil lines must be vented so that there is air in the oil system.
With regular 912 ULS is not a problem. The compressed air and rotating propeller around to a steady stream out of oil without air.
But with ULS3 this is a problem. I can stand for 20-30 minutes and turn around the propeller (with compressed air in the tank) without a steady stream of oil. The oil that comes out contains air.
One way is to remove a temp plug on each of the cylinders, I can then crank the propeller fast enough around to a steady stream of oil out.
But according Heavy manual you should not not remove a temp plug from each sylynder. Because then disappear compression. It shall be compression when bleeding the air from the oil system.
In Sweden there are 5-6 new 912 ULS3 engines with MT propellers (hydraulic governor) who have had problems. The problem disappeared when changing the hydraulic tappets. This suggests that the engines have not been properly vented of air in the oil system of the aircraft manufacturer.
Can anyone tell me practice how bleeding the oil on a 912 uls3?
