AOC 15 user manual Procedure for Bolt Replacement Requiring Loctite

Appendix J-3 Loctite Procedures 169

Procedure for Bolt Replacement Requiring Loctite

The Loctite Specification Sheets should be read and followed precisely. If it is not feasible to follow specification sheet exactly, it is imperative that the vendor be contacted and asked the consequences of such action (1-800-LOCTITE).

(1)It is very important to remove and replace only one bolt at a time when reinstalling any bolts so that preload is distributed evenly between all bolts.

(2)The surfaces of both the inserts and bolts must be CLEAN and DRY. A cleaning solvent must be used to remove all 242/271 residues and any grease, rust or dirt. A wire brush is usually necessary. Permatex Brake and Parts Cleaner or Loctite 22355 Cleaner & Degreaser (formerly Loctite 7070) is the recommended product.

(3)All AOC parts used in conjunction with Loctite are considered Inactive Metals (see Loctite specs). Therefore, the surfaces for all AOC applications must be primed before Loctite is applied! The threads should all be sprayed with Permatex Klean’N Prime or Loctite 7649 Primer-N.

(4)After surfaces have been prepared and have completely dried, apply Loctite to threads of the bolt. (An few air blasts may be helpful in blowing excess cleaner and primer from the inserts if applicable. This will also improve drying time.) A thin layer covering all threads on the bottom three-quarters of the bolt will be sufficient. (Be careful on blade bolts not to over apply Loctite, as excess Loctite will allow the washer to slip when applying torque, causing misalignment.) Do not apply Loctite to wet surfaces, as the bonding properties will be affected.

(5)Torque bolt to recommended value . For blade bolts, it is extremely important that blade washers be aligned properly and are well seated in the counterbore. If washers are misaligned, remove torque realign and apply specified torque once again. Loctite will fixture within 5 to 20 minutes after which blades and yaw bearing may be moved around. However, the Loctite must be allowed to cure 24 hours before any dynamics are initiated into the system (i.e. running the machine).

NOTE: The specification sheets show a procedure for applying Loctite to blind holes. In our blade/hub assembly procedure, this is not practical as there is a fairly large reservoir in the bottom of the insert. In this case, it is acceptable to apply the Loctite on bottom half of the bolt, as pressure will push the Loctite towards the top. In addition some may be applied to the insert also.

NOTICE: Use of the material contained in this document is subject to the warning on page Iv and the disclaimer on page v of this document.

DOC012R02 AOC 15/50 User Manual Nov 2001