Service Bulletin No. 2994

Transcription

1 MODEL TYPE SECTION/GROUP DATE E / J Series Coaches equipped with Linnig Fan Clutch Service Information 6--Cooling July 30, 2008 SUBJECT CONDITIONS LINNIG FAN CLUTCH MOUNTING NUTS Parts may be purchased from MCI Service Parts, Louisville, Kentucky or from MCI ServiceParts,Newcastle,Ontario. Description: MCI has made a design change to the Linnig fan clutch installation. Removing the paint from the surface of the bracket where the nuts contact the brackets and re---torquing the nuts to the required torque will reduce the probability of the clutch mounting nuts working loose. This service information bulletin is applicable to E / J model coaches between the range of, and including, unit numbers Parts Qty. New P/N Description Nut, Flanged, Prevailing Torque a/r 15G-1-43 Torque Seal a/r Loctite 271 a/r T Stud, M , Gr. 8.8 a/r Loctite 603 a/r Loctite, Blue Service Information: 1. New parts will be available for service replacement. Service Procedure: General notes Read this entire procedure before beginning work. UseSafeShopPracticesAtAllTimes. To avoid personal injury, never enter or perform work in the engine compartment prior to positioning the ENGINE RUN and ENGINE START switches on the engine remote box to the OFF position. When performing work in the engine compartment always allow enough time for engine components to cool down to ambient temperature, eliminating the risk of burns. 1. Turn the main battery disconnect switch to the OFF position. Chock both sides of the tires. 2. Open the engine door. Position the ENGINE RUN and ENGINE START switches on the engine remote box to the OFF position.

2 Service Bulletin No DATE JULY 30, 2008 PAGE 3. Locate the Linnig fan clutch ( refer to Figure 1 ). Figure 1. Loosen the six pulley mounting capscrews 1/2 turn only. DO NOT completely remove the capscrews. 4. Locate the six ( 6 ) clutch pulley mounting capscrews ( refer to Figure 2 ). Brake loose the six clutch pulley mounting capscrews. 5. Adjust the belt tensioner to release tension from the belt. Remove belt from the clutch pulley. 6. Remove and retain the six ( 6 ) clutch pulley mounting capscrews ( refer to Figure 2 ). Remove clutch pulley and place it aside, to be re---installed at a later step in this procedure. clutch pulley mounting capscrew Figure 2. 2

3 DATE JULY 30, 2008 PAGE 3 7. Inspect clutch for broken mounting studs. If any of the mounting studs are broken, all four ( 4 ) studs must be replaced. Upon inspection, if a mounting stud is broken perform Steps 8. to 18. Upon inspection, if NO mounting studs are broken proceed to the top of Page 4, and perform Steps 19. to Disconnect clutch from driveshaft. Retain all mounting hardware to be re-installed at a later step in this procedure. Carefully disengage the clutch from the driveshaft. 9. Carefully remove the clutch from the coach and place on a workbench to remove the studs. If an extractor bit is required to remove the broken stud ( broken at or below the surface ), use a drill stop collar set to a depth of 0.30 maximum to prevent the bit from drilling into the clutch coil ( Figure 3 ). 10. Using a metric M tap, remove all burrs from internal threads. broken mounting stud Figure Apply Loctite 603 to the threads of new mounting stud ( p/n T ). Install mounting stud. Torque to 36 ft-lbs. 12. Remove the paint from the surface area of the bracket where the nut contacts the bracket ( Figure 5 ). 13. Position and orientate the clutch to the coach mounting bracket, ensuring the harness is routed through the notch at the 6:00 position. Fasten the clutch using new clutch mounting nuts ( p/n ). Torque to 50 ft-lbs. Apply torque seal to fastener. 14. Apply blue Loctite ( p/n ) to the threads of the mounting hardware removed in Step 8. Fasten the drive shaft to the clutch.. Torque to 58 ft-lbs. 15. Using clean shop air, blow out the pulley mounting holes. Using capscrews removed in Step 6. and Loctite 271, re-install the clutch pulley. Torque capscrews to 18 ft-lbs. Apply torque seal to fasteners. 16. Position the belt on the clutch pulley. Verify proper belt tension. Proper belt tension is attained when pounds of force are applied in the mid---span of the belt produces 1/2 inch deflection at mid---span. 17. Torque tensioner adjustment lock nuts to ft-lbs. 18. Position the ENGINE RUN and ENGINE START switches on the engine remote box to the ON position. Close the engine door. Procedure complete for clutches with broken studs.

4 Service Bulletin No DATE JULY 30, 2008 PAGE 4 Only remove one clutch mounting nut at a time ( Step19. / Figure 4 ) ( this allows the clutch to remain in the coach during paint removal ). 19. Remove and discard one clutch mounting nut ( refer to Figure 4 ). 20. Remove the paint from the surface area of the bracket where the nut contacts the bracket ( refer to Figures 4 and 5 ). clutch mounting nut Figure 4. remove the paint from the surface area where the nut contacts the bracket removal of paint Figure Install new mounting nut ( p/n ). Torque to 50 ft-lbs. Apply torque seal to fastener.

5 DATE JULY 30, 2008 PAGE 5 Repeat steps 19. to 21. to remaining mounting nuts, removing only one clutch mounting nut at a time. 22. Using clean shop air, blow out the pulley mounting holes. Using capscrews removed in Step 6. and Loctite 271, re-install the clutch pulley. Torque capscrews to 18 ft-lbs. Apply torque seal to fasteners. 23. Position the belt on the clutch pulley. Verify proper belt tension. Proper belt tension is attained when pounds of force are applied in the mid---span of the belt produces 1/2 inch deflection at mid---span. 24. Torque tensioner adjustment lock nuts to ft-lbs. 25. PositiontheENGINERUNandENGINESTARTswitchesontheengineremotetotheONposition. Close theenginedoor. Procedure complete.