YellerDaisy
Well Known Member
Question regarding a very old Lycoming O-360-A1A (pre 68?) that has crankshaft sludge tubes (or "Crank Pin Oil", part #71577).
I'm having this engine overhauled and my mechanic has no experience with the crankshaft sludge tubes. His question is: Should replacement sludge tubes completely seal?
The new sludge tubes installed about like we expected and they look good/normal. To confirm that they set correctly, we sealed the oil galley hole in the crankshaft main journal and applied air pressure (120psi) to the oil hole in the connecting rod journal. A little air leaks out from around the sludge tube (and it is at 120psi). We're not sure if this is normal or if anyone has ever bothered to even test this.
I would love to hear something that will set my mechanics mind at ease.
Btw, the Lycoming overhaul manual doesn't offer much (Item 7-61 in my version 60294-7-13) - at least that I've found. It just says to drive the new tubes in to the correct depth.
Thank you!!
I'm having this engine overhauled and my mechanic has no experience with the crankshaft sludge tubes. His question is: Should replacement sludge tubes completely seal?
The new sludge tubes installed about like we expected and they look good/normal. To confirm that they set correctly, we sealed the oil galley hole in the crankshaft main journal and applied air pressure (120psi) to the oil hole in the connecting rod journal. A little air leaks out from around the sludge tube (and it is at 120psi). We're not sure if this is normal or if anyone has ever bothered to even test this.
I would love to hear something that will set my mechanics mind at ease.
Btw, the Lycoming overhaul manual doesn't offer much (Item 7-61 in my version 60294-7-13) - at least that I've found. It just says to drive the new tubes in to the correct depth.
Thank you!!
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