74-18-05 SLICK ELECTRO, INC: Amendment 39-1930. Applies to slick magneto Models 447, 662, 664, 667, 668, 676, and 680 manufactured prior to August 1973 with Serial Numbers 3080608 and below.
Compliance required as indicated, unless already accomplished.
To prevent failure of the magneto impulse coupling due to loose pawls, accomplish the following:
A. Prior to the accumulation of time in service which corresponds to the engine manufactures recommended overhaul period or within the next 100 hours, whichever is later, after the effective date of this AD, all magnetos with S/N's 3080608 and below must have the old impulse couplings replaced with new couplings listed below:
Slick Magneto Models - 662 and 680; Impulse Coupling Complete - M-2369
Slick Magneto Model - 664; Impulse Coupling Complete - M-2370
Slick Magneto Model - 667; Impulse Coupling Complete - M-2371
Slick Magneto Model - 668; Impulse Coupling Complete - M-2372
Slick Magneto Model - 676; Impulse Coupling Complete - M-2373
Slick Magneto Model - 447; Impulse Coupling Complete - M-2374
Note: Reference Slick Service Letter 1-73.
B. Magnetos manufactured prior to November 1970 with serial numbers 0110000 and below which have not accumulated sufficient time in service to require replacement in accordance with Paragraph A above, must be inspected within the next 100 hours' time in service or at the next annual inspection, whichever occurs first, after the effective date of this AD and thereafter at intervals not to exceed 500 hours' time in service from the last inspection until impulse couplings are replaced in accordance with paragraph A above.
C. Magnetos manufactured between November 1970 and August 1973 with serial numbers 0110001 through 3080608, which have not accumulated sufficient time in service to require replacement in accordance with Paragraph A above, require a one time inspection. This inspection must be accomplished within the next 100 hours time in service after the effective date of this AD or at 500 hours total time in service whichever is later.
D. The following method is to be used when accomplishing inspection required by Paragraphs B and C above.
(1) Remove the impulse coupling hub from the shaft and inspect the pawl rivets for looseness. Use a pair of pliers on the head of the rivet; use caution with the pliers so as not to damage the head of the rivet. If the rivet turns in the plate, the hub assembly should be replaced. (See paragraph A for correct replacement assemblies.)
(2) For proper spring tension in reassembly, refer to instructions on page 25 of Slick Green Service Manual (Form No. 1012), or page 27 in their yellow Service Manual (Form No. 1020).
Notes: (a) Reference Slick Service Bulletin No. 1-71.
(b) Use Slick Service Letter 1-74, when removing couplings in accordance with Paragraph D above.
This supersedes Amendment 39-1809 (39 F. R. 12337), AD 74-08-05.
This Amendment becomes effective August 28, 1974.