** fsm typo; read this or engine damage may occur!!! **

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FinalImpact

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All,
Here are a couple of observations about the Yamaha Factory Service Manual (FSM) which if followed MAY RESULT IN DAMAGE TO THE VEHICLE!
1) Typo stating to turn the engine counter clockwise = WRONG -> Clockwise is correct!
2) Torque Oil Drain Plug to 31 ft/lbs = cracked pan if A USED washer and Oiled Threads are present!
3) Torque Rear Sprocket Studs/Nuts Torque to 72ft/lbs = Damaged threads if GREASE/OIL is Present on threads/washer!

Follow Post FSM ERRORS, Read this or Risk Damage to your Vehicle! Comment and post your input here.

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1) TIMING CHAIN & VALVE ADJUSTMENT ERROR TYPO!
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Production Literature:
LIT-11616-20-60 (S2) PAGE 89 of Section 3-4 is one area...
LIT-11616-17-50 (S1) PN 5VX-28197-10, indicates the SAME ERROR
  • Only rotate the crankshaft CLOCKWISE!! while performing repairs of any kind!
  • The critical error tells the user to rotate the engine COUNTER CLOCKWISE! Doing this action MAY damage the Timing Chain Tensioner, timing chain guides and/or the sprag clutch used in the engines Starter Motor!
The ERROR in literature reads as follows in red:
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ADJUSTING THE VALVE CLEARANCE
The following procedure applies to all of the valves.
a. Turn the crankshaft counterclockwise.
b. When piston #1 is at TDC on the compression stroke, align the TDC mark “a” on the pickup rotor with the crankcase mating surface “b”.

It should read:
** a. Turn the crankshaft clockwise. **

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DETAILS:
The timing chain is on the right side of the engine with the tensioner on rear of the engine block. Chains are meant to be pulled, much like a rope is pulled. As such, when the crankshaft is rotated clockwise it pulls the chain from the head, downwards to the crankshaft. Once past the crankshaft there is less load on the chain and the tensioner applies pressure to the guide to keep the chain taunt to reduce noise and wear.

Rotating the engine BACKWARDS (counterclockwise ) pulls the chain taunt against the Cam Chain Tensioner and guides. This may break the guides or depress the mechanical ratchet internal to the CCT and damage it. It also acts upon the Starters Sprag (one way clutch) spinning the starter motor backwards.

OUTLINE OF CCT, GUIDES AND CHAIN:
Right side of Engine, Cam Chain Tensioner on the Rear:



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2) OIL PAN DRAIN BOLT / DON'T CRACK THE PAN!
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Torque Spec: 31 Ft/Lbs, 43 Nm (4.3 m·kg)
- The FSM states to USE A NEW GASKET!!
- The FSM states ALL THREADS ARE CLEAN AND DRY!! < NOT OILED!
By Reusing the gasket AND having oiled threads YOU RISK BREAKING THE OIL PAN USING 31Ft/lb setting!!!

Read up on Metric ISO Bolt Torque Specification (ISO 898).
In **most cases** oiled threads require a torque reduction of 25%! In addition, a used washer is compressed, smooth and slippery when oiled. This reduces the friction between the Bolts Hex Head and the Oil Pan! Meaning: @31ft/lbs the TENSION APPLIED AT THE THREADS IS GREATER THAN THE PANS STRENGTH! This bolt only needs to stay secure and Not leak oil!

** BOTTOM LINE **
** TORQUE NEW WASHERS WITH DRY THREADS & DRY WASHER TO 31 Ft/Lbs!!!
** DO NOT TORQUE USED WASHERS WITH OILED THREADS TO 31 Ft/Lbs!!!

** RULE OF THUMB **
** REDUCE TORQUE BY 25% FOR OILED THREADS! (31 X 0.25 = 7.75ft/lbs)**
** USED WASHERS DECREASE FRICTION BETWEEN THE BOLTS HEAD AND THE OIL PAN!
** BECAUSE ITS AN OIL PAN AND OIL IS DRIPPING OUT, OIL IS ON THE WASHER!! REDUCE TORQUE BY 10% (31 X 0.10 = 3.1ft/lbs)!

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3) REAR SPROCKET STUDS/NUTS TORQUE TO 72 FT/LBS
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** 72Ft/lbs may result in DAMAGED THREADS IF THERE IS ANY TRACE OF LUBRICANT ON THE THREADS OR WASHERS!
** Clean these surfaces thoroughly with brake cleaner LEAVING NO LUBRICANT ON THE STUDS, NUTS, OR WASHERS!
** Lubricants reduce friction and the tension applied to the fasteners may exceed the actual STRENGTH OF THE MATERIALS!
** Read the FSM - CLEAN, DRY THREADS = NO LUBRICANTS!!!! THIS INCLUDES LOCTITE!

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  • When A BOLT STOPS TURNING, BE CAREFUL! SOMETHING MUST GIVE!
  • REMEMBER: Torque as seen by a Torque wrench is AN INDICATOR of tension being applied to a fastener!
  • BOLT STRETCH is the ACTUAL MEASURE OF TENSION APPLIED TO OBTAIN CLAMP FORCE!!
  • Oiled threads and washers reduce surface tension between the bolt head and the surface being clamped.
  • YOU MUST ACCOUNT FOR OILED THREADS VS DRY THREADS
************************************

EDIT LIST:
2014-11-19 Added new pic, Added drain plug, Added rear sprocket
2014-11-18 Reduced verbage
 
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