It is quite difficult to diagnose the health of a gearbox by the noise it makes. If you are unable to pinpoint the source of the noise, contact a qualified technician.

Cause of failure (Remedy)

Noise in the gearbox. Noise decreases or disappears when the clutch is depressed:

  • - Insufficient oil level in the gearbox housing (Check the level, add oil if necessary, check for leaks, clean or replace the breather if necessary)
  • - Poor oil quality. Water has entered the oil (when water enters, the oil will form a white emulsion) (Change the oil)
  • - Worn or damaged bearings, gear teeth (Replace worn bearings, gears)

Gears are difficult to turn on, there are no extraneous noises:

  • - Looseness of the shift forks on the stems due to loosening of the stop bolts (Tighten the bolts of the shift forks on the stems)
  • - Burrs on the teeth of the sliding sleeves of the synchronizers (Cut off the burrs with a needle file)
  • - Wear on the pin holes on the bottom of the shift lever (Replace the bottom of the lever)
  • - Clutch won't turn off (Repair clutch)

Transmissions spontaneously turn off:

  • - Damaged or worn splines on the clutch, gear or synchronizer hub (Replace defective parts)
  • - the bolts of the gearbox to the clutch housing and / or the clutch housing to the engine are not tightened (Tighten the mounting bolts)
  • - Lost elasticity or collapsed detent springs, worn rods (Replace defective parts)

Noise, crackle, squeal of gear couplingswhen the gear is engaged:

  • - Clutch does not fully disengage (See Clutch Troubleshooting)
  • -Low oil in gearbox housing (Add oil, check for leaks, clean or replace breather)
  • - Worn or deformed shift synchro ring (Replace ring)

Oil leak:

  • - Wear of cuffs (Replace cuffs, if necessary, clean or replace the breather of the gearbox)
  • - Strong wear, nicks on the surfaces of the shafts on which the edges of the cuffs work (Smooth out minor damage - with fine-grained sandpaper and polish)

When installing a new cuff, you can slightly underpress it, avoiding distortion (if necessary, placing distance washers up to 1 mm thick under it) so that the edge of the cuff works on the unworn part of the shaft. In case of significant damage, replace the shafts and cuffs

  • - Increased pressure in the gearbox due to clogged breather (Clean or replace the breather of the gearbox)
  • - Loose gearbox housings, front cover or shift lever housing, gaskets damaged (Tighten threaded connections) Replace gaskets (sealant can be used when installing them)
  • - Drain and fill plugs loose (Tighten the plugs, you can put them on the sealant)