Final Drive (Task No 9) - Monday 9th February 2015

Final Drive
Bench Unit

Today has been much awaited, as it signaled the start of our final Level 3 Practical Assessments!  I was assigned the Final Drive Task upon their commencement, though in my eagerness, I omitted to take photographs of the disassembled unit and the hitherto associated individual components!  However, with a bit of improvisation and initiative, I will obtain these at a later date (hopefully tomorrow if someone else is assigned the same task), and will then include them within this post in order to support the diagnosis that I have arrived upon regardless.

Plan:  Gather tools and equipment and retrieve relevant vehicle information.  Dismantle and check all Final Drive composite components and provide analysis of their condition.  Call Tutor. Reassemble to manufacturer's specifications, especially regarding torquing sequences, tolerances of Rolling Torque, Backlash, Cap Spread and Cap Bolt Torques.  Call Tutor. Provide information as per selected knowledge questions.  Provide Level 3 standard drawing of gear mesh (Pinion to Crown Wheel) contact variations. Report to Tutor. Clean and account for all tools and equipment, tidy work area and then assist with Workshop housekeeping duties as necessary.

Analysis & Report

Bearing Type (Pinion): Needle Roller Bearings - Both require re-packing with GP Grease, but one set is currently seized to Pinion Shaft.  Recommend purchase and installation new set of Bearings (x2).  Recommend also replacement of the Pinion Shaft Roller Bearing Mating Surface Races (x2).

Collapsible Spacer:  Recommend renewal of spacer.  Length measured using Micrometer:
55.44mm.

End Cap Outer Races: Worn & Pitted.  Recommend replacement.

End Cap Adjusters: Serviceable.

End Cap Inner Needle Roller Bearings:  Both are dry and worn.  Recommend replacement (x2).

Crown Wheel & Pinion: Wear pattern indicates excessive backlash, however they both appear serviceable for further use, upon correct re-adjustment, and with the aforementioned renewed associated components.

Planetary Gear Set Roll Pins:  3 of 3 Intact and serviceable.

Inner Planetary Gear Set:  Not requested to be examined.

Replacement of specified quantity and grade of EP Transmission Oil, as per manufacturer's specifications.

Tools & Equipment:  All accounted for.

Comment:  Many thanks to Julian Jones (Assessor), who put me at ease in a situation I was previously apprehensive of, but then events and knowledge flowed - and I thank you muchly!