General Repair Instructions
General Repair Instructions
The maximum possible care, cleanliness and proper tools are essential to ensure satisfactory and successful transmission repairs. The usual basic safety precautions also apply when carrying out vehicle repairs.
A number of generally applicable instructions for individual repair procedures, which are otherwise mentioned at various points in the repair information are summarized below.
Transmission
• When installing the transmission, make sure that the alignment sleeves between the engine and transmission are correctly positioned.
• When assembling mounting brackets as well as other waxed components the contacts surfaces must be cleaned. Contact surfaces must be free of grease and wax.
• When replacing a transmission, gear oil must be filled up to lower edge of fill hole.
• Capacity --> [ Code Letters, Allocation and Capacities ] Code Letters, Allocation and Capacities.
Gaskets O-rings, and Seals
• Always replace O-rings, gaskets and seals.
• After removing gaskets and seals, always inspect contact surfaces at housing or shaft for burrs and damage and repair them.
• Before installing radial shaft seal, fill space between sealing lips- arrow - half way with sealing grease (G 052 128 A1).
• After installing, check transmission oil level --> [ Transmission Oil, Checking ] Transmission Oil, Checking.
• Lightly lubricate O-rings with transmission oil before installing, this prevents the rings from being damaged when inserting.
• Always clean joint surfaces and apply sealant (AMV 188 200 03).
• Apply sealant uniformly, but not too thick.
Locking elements
• Replace circlips.
• Do not over stretch circlips.
• Circlips must be properly seated in base of groove.
• Replace spring pins. Installation position: Slit longitudinal to direction of force
Bolts and Nuts
• Loosen and tighten bolts and nuts for securing covers and housings in a diagonal sequence.
• Especially delicate parts e.g. clutch pressure plates must not be distorted and must be loosened and tightened in stages in a diagonal sequence.
• The tightening specifications stated apply to unoiled bolts and nuts.
• Always replace self locking nuts and bolts.
• For all hose connections, it must be checked that contact surfaces as well as bolts and nuts, if necessary, are to be waxed only after installation.
• Use thread tap to remove remains of locking fluid from all threaded holes in which self locking bolts are to be screwed. Otherwise there is a risk that the bolts will shear the next time they are removed.
Bearings
• Install new tapered roller bearing as supplied and do not use additional oil.
• Install needle bearings with lettering on bearing (the side with thicker metal) facing the drift.
• Taper roller bearings installed to one shaft must be replaced as a set. Use same make of bearings.
• Heat inner races to approximately 100° C before installing.
• Do not interchange inner and outer bearing races with those from other bearings of the same size, bearings are paired.
Adjustment Shims
• Measure shims at several points using a micrometer. Varying tolerances make it possible to measure the required shim thickness exactly.
• Check for burrs and signs of damage.
• Install only shims that are in perfect condition.
Synchronizer Rings
• Do not interchange. If reusing synchronizer rings, always install to same gear.
• Check for wear and replace if necessary.
• Check groove - arrow 1 - of synchronizer ring - A - and inner race for flat areas (grooves are worn).
• The coating must not be damaged on coated synchronizer rings.
• If an intermediate ring - B - is installed, check intermediate ring on outer contact surface - arrow 2 - and inner contact surface - arrow 3 - for "grooves", "scoring " and "blue coloring (from overheating".
• Check taper of selector gear for "scoring" and " grooves"
• Coat synchronizers with gear oil before installing.
Gear
• Before pressing on, clean and heat to max. 100° C on a heater.
• Temperature can be check using temperature tester (V.A.G 1558), ignition tester (V.A.G 1767) or diesel tester (V.A.G 1743).