Harry R Sierra MC 360 1975 AD Airworthiness Directive 96-09-10 C
Gang, I am coming up to 2000 hours and it seems this AD requires an oil pump or impeller replacement. Does anybody has some details around the cost of the parts, where to buy them and the level of effort ie how many hours to do that job?? Anything else I should be aware of?? Anything else I should be doing etc ?? Any kind of information is welcome.
Well, I found some more information. My engine was overhauled in 1994 by Magnum Aircraft Engines in Ontario (Ca). I have a detailed parts list for items that were replaced at that time and I have :
Part # SL78528 Pump housing (1 item)
Part # SL18109A-5 Impeller set
Part # SL75441-1 Gasket set
Can anybody tell me if this is the part number for the impeller that needs to be replaced as per the AD or am I lucky and this is the new replacement part number??
Technical Editor:
I found the following info in about two minutes using the BAC search function on the MML Archives. It is from one of Bob Steward’s MML postings on January 22, 2001. I will post the following on BAC in FAQ.
From: Bob Steward
96-09-10 specifically requires removal of the aluminum and steel pair in favor of an all steel set with one carburized and one nitrided. (Kit P/N 05K19423-S)
From the text of the AD:
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CAUTION
Although the steel driving impeller P/N 60746 is superseded on all models except GO-435 and GO-480 and is still a functional in-service item on these engines, it must not be used with new impellers.
In Parts Data above, Driven Steel Impeller Assy. P/N LW-18110 supersedes Aluminum Driven Impeller and Shaft Assy. P/N LW-13775.
Aluminum Driven Impeller and Shaft Assy. P/N LW-13775 is a discontinued item. In order to avoid confusion and prevent inadvertent mixing of gears, P/N LW-13775 must be returned to your authorized distributor along with the appropriate paperwork to receive full credit. This applies only to current “on shelf” inventory. It is not applicable to impellers already installed in any engines.
To insure new impellers are used together, they must be purchased in a Kit P/N 05K19423-S.
EDITOR’s NOTE:
This AD mandated compliance by no later that July 15 of 2001. All these engines should have been updated long before now.
Here is the documented Lycoming-numbered parts list that complies with the AD:
AL05K19423S Oil pump gear replacement kit (nitrided/carburized gears)
SL18109A-S Superior Airparts equivalent kit
LW-18109 Nitrided oil pump driving impeller
LW-18110 Carburized oil pump driven impeller and shaft assy
78528 Oil pump housing, one-piece with oil feed passage
78531 Oil pump housing, one-piece
Harry, I think that your SL18109A-5 number is really the SL18109A-S. It is common for the 5 and the S to be both mis-written and mis-read, on this and other parts. You should be in good shape. Having said this, since this AD was mandatory as of July 15 of 2001, please keep looking in your engine and airframe logbooks. There should be an entry there somewhere, by an A&P or A&P-IA, that clearly states that this AD was complied with by installing the Superior kit during overhaul. Check for the entries back in that timeframe.