Engine Components Inc. (ECi) plasma-faced top compression rings fitted to Lycoming and Teledyne Continental Motors (TCM) series engines as listed in the table below:
Engine: |
Type: |
Ring P/N: |
Ring Set P/N: |
Lycoming |
320/360/540 (5,125 inch bore) |
AEL74241PL |
ST203 & CN203 |
TCM |
470 |
AEC648009PL |
ST106 & CN106 ST108 & CN108 |
TCM |
520/550 |
AEC648005PL |
ST110 & CN110 |
This Continuing Airworthiness Notice (CAN) advises operators of engines listed in the above table to establish if ECi plasma-faced top compression rings are fitted to the engine, if an increase of oil venting from the crankcase breather is experienced in conjunction with the oil turning to a dark colour.
These symptoms usually develop within the first 100 hours TIS after installation of new rings.
Engine Components Inc. (ECi) Service Instruction No. 06-6 dated 23 October 2006 pertains to the subject of this CAN. A copy is available on the ECi website at http://www.eci2fly.com(external link)
The P/N of Lycoming ring set corrected to CN203 in revision 1 of this CAN. Engine Components Inc. (ECi) and the NZ CAA have received numerous reports of oil turning black with an increase of oil loss out the crankcase breather on engines fitted with ECi plasma-faced top compression rings. Investigation revealed delamination of the plasma coating on the top compression ring. The cause of the delamination is a combination of poor adhesion of the plasma-fill coating combined with high heat at the top compression ring face.
Operators that experience an increase of oil venting from the crankcase breather in conjunction with the oil turning to a dark colour should establish if ECi plasma-faced top compression rings are fitted to the engine. Top compression rings which show any signs of delamination of the plasma coating should be replaced per ECi Service Instruction No. 06-6 and the engine manufacturer instructions.
Note: Refer to ECi Service Instruction No. 06-6 for further information.