This STC Kit is authorized for Ercoupe Models 415-C, CD, D, E, G, F-1, F-1A, A-2, A2-A and M10 aircraft SN 813 and above.
It is intended to correct chronically leaking Main Landing Gear (MLG) Oleo Struts caused by an inadequate "O" ring seal.
The kit includes the necessary modification parts and instructions to modify both MLG Oleo Strut Assemblies.
The MLG piston "O" ring seal is removed and the piston is reworked by enlarging the orifice hole and cutting threads to accommodate the installation of an AN4-5A bolt which is modified to provide the orifice function. The final assembly includes mounting an automotive style cup seal; similar to the arrangement found on early Model 415-C aircraft, serial numbers 112 thru 812.
The finished assembly is replenished with DOT 3 automotive brake fluid as shown in the Ercoupe Service Manual for Model 415-C aircraft, serial numbers 112 thru 812.
The use of MIL 5606 (Red) hydraulic fluid in the MLG Oleos is discontinued.
When accomplished in conjunction with an Annual/100 Hour Inspection, the additional labor requirement is approximately 1 hour.