Inspection and troubleshooting of GAZ-2705 gearbox parts
Wash thoroughly the parts and components of the gearbox and blow with compressed air
Carry out an external inspection of parts and assemblies.
Replace damaged gaskets.
Check the condition of the shafts. If there is piping (shells) on the bearing journals and seats, or signs of visible wear, the shafts must be replaced.
When replacing the input shaft, it is necessary to check the ease of its movement in the clutch driven disc.
To do this, you need to insert it into the splined hole of the driven disk (the clutch does not need to be disassembled) and move the input shaft in the longitudinal direction.
Check the condition of the gearbox gears.
If there are chips and chipping of the teeth, or burrs on the surfaces of the holes, replace the gear.
Check the condition of the bearings.
If there is piping (shells) on the running tracks and rolling elements, traces of indentation of the rolling bodies on the running tracks, damage to the separators, replace the bearings.
Check the status of synchronizers.
If there are chips and nicks on the splines of the hub and sliding coupling, wear of the crackers and breakage of the springs, the synchronizer must be replaced.
Check the condition of the synchronizer blocking rings.
If there are nicks and chips on the gear rims, or significant wear on the cones, replace the blocking rings.
Check the gap between the gears and the corresponding locking rings, which should be within 1.1-1.5 mm.
Otherwise, the locking ring must be replaced.
Check the condition of the gear shift rods.
If there is bent, burrs or burrs, the hole for the locking pin is loose, or holes for the clamps are worn out, the rods must be replaced.
Check the condition of the gear shift forks.
If there is wear on the legs and the fork is bent, replace it.
If oil leakage through the seals is detected during operation, as well as wear of the working edges, replace the seals.
Check the condition of the gearbox housings.
If cracks, nicks and deep scratches are detected on the mating surfaces, collapse and wear in the bearing housings, replace the crankcase.
If burrs and deformation are detected on the thrust washers and lock rings, as well as if the lock rings lose their elasticity, they must be replaced.
Nominal dimensions and fit of mating parts of the gearbox
Name of part Nominal diameter, mm / Name of mating parts Nominal diameter, mm
- Input shaft bearing 80 –0.030 / Front gearbox housing 80 –0.011
- Secondary shaft bearing 75 –0.011 / Rear gearbox housing 75 +0.030
- Gear block bearing 62 –0.013 / Front gearbox housing 62 +0.030
- Gear block bearing 62 –0.013 / Rear gearbox housing 62 +0.030
- Reverse intermediate gear 24 +0.020 24 +0.007 / Reverse intermediate gear axis, needle bearing 18 –0.011 + 2·3 –0.010
- Gears 2nd, 3rd, 5th gears 42 +0.025 42 +0.009 / Secondary shaft, needle bearing 37 –0.090 + 2·2.5 –0.010 37 –0.025 + 2·2.5 –0.010
- 1st gear and reverse gears 47 +0.025 47 +0.009 / Secondary shaft, needle bearing 42 –0.090 + 2·2.5 –0.010 42 –0.025 + 2·2.5 –0.010
- Input shaft 30.254 +0.025 / Secondary shaft, roller bearing 19.235 –0.013 + 2 5.5 –0.007
- Synchronizer hub 1st, 2nd gears 2.847 +0.023 2.847 +0.063 spline width / Secondary shaft 2.847 -0.063 2.847 -0.023 spline width
- 5th gear and reverse synchronizer hub 2.847 +0.063 2.847 +0.023 spline width / Secondary shaft 2.847 -0.023 2.847 -0.063 spline width
- 3rd, 4th gear synchronizer hub 1.441 +0.063 1.441 +0.023 spline width / Secondary shaft 1.441 -0.023 1.441 -0.063 spline width
- Synchronizer sliding sleeve 4.181 +0.080 4.181 +0.030 spline width / Synchronizer hub 4.181 -0.030 4.181 -0.080 spline width
- Cardan sliding fork 2.068 +0.045 2.068 +0.030 spline width / Secondary shaft 42.068 –0.080 42.068 –0.120 spline width
- Front and rear parts of the gearbox housing 14 +0.075 14 +0.032 / Gear shift rod 14 –0.011
- Intermediate shaft drive gear 35 +0.014 35 –0.011 / Intermediate shaft 35 +0.076 35 +0.060
- Intermediate shaft 2nd gear 38 +0.014 38 –0.011 / Intermediate shaft 38 +0.076 38 +0.060
- 3rd gear intermediate shaft 37 +0.014 37 –0.011 / Intermediate shaft 37 +0.076 37 +0.060
- 5th gear gear 35 +0.014 intermediate shaft gear 35 +0.014 35 –0.011 / Intermediate shaft 35 +0.07 6 35 +0.060
- Steelbabbit bushing 38 +0.015 / Cardan sliding fork 38 –0.025 38 –0.050
- Forks and heads of gear shift rods 14 +0.024 14 +0.006 / Gear shift rods 14 –0.011
- Rear gearbox housing 8 +0.051 8 +0.025 / Plunger 8 –0.058
- Synchronizer sliding clutches 8 –0.250 / Shift rod forks 8.5 +0.015
- Shift mechanism housing (spherical surface) 35 –0.100 / Shift lever (spherical surface) 35 –0.100 35 –0.350
- Gear shift rod head 14 +0.160 14 +0.050 groove width / Gear shift lever (lower part) 14 –0.240 spherical surface
- Gear shift lever (bottom) 6.2 +0.200 groove width / Pin 6 –0.048
Part name Clearance, mm / Preload, mm min max min max
- Input shaft bearing 0.000 0.041 /__ __
- Secondary shaft bearing 0.000 0.041 /__ __
- Gear block bearing 0.000 0.043 /__ __
- Gear block bearing 0.000 0.043 /__ __
- Reverse intermediate gear 0.007 total 0.051 total /__ __
- Gears 2nd, 3rd, 5th gears 0.018 total 0.070 total /__ __
- 1st gear and reverse gears 0.018 total 0.070 total /__ __
- Input shaft 0.019 total 0.071 total /__ __
- Synchronizer hub 1st, 2nd gears 0.046 0.126 /__ __
- 5th gear and reverse synchronizer hub 0.046 0.126 /__ __
- Synchronizer hub 3rd, 4th gears 0.046 0.126 /__ __
- Synchronizer sliding clutch 0.060 0.160 /__ __
- Sliding fork of cardan transmission 0.100 0.165 /__ __
- Front and rear parts of the gearbox housing 0.032 0.086 /__ __
- Intermediate shaft drive gear __ __/ 0.046 0.087
- Intermediate shaft 2nd gear __ __/ 0.046 0.087
- Intermediate shaft 3rd gear __ __/ 0.046 0.087
- Intermediate shaft 5th gear __ __/ 0.046 0.087
- Steelbabbit bushing 0.025 0.065 /__ __
- Forks and heads of gear shift rods 0.006 0.035 /__ __
- Rear gearbox housing 0.025 0.119 /__ __
- Synchronizer sliding clutches 0.500 0.900 /__ __
- Shift mechanism housing (spherical surface) __ __ /__ __
- Gear shift rod head 0.050 0.400 /__ __
- Gear shift lever (lower part) 0.200 0.448 /__ __