Autopapyrus · Moskvich 2140 (1988) 1.5 UZAM-412DE
https://autopapyrus.com/guides/moskvich/2140/alternator-drive-belt-replacement-and-tensioning/
https://autopapyrus.com/guides/moskvich/2140/alternator-drive-belt-replacement-and-tensioning/
Compiled automatically from service literature and owner experience. Specs are for the typical configuration — check them against your exact car before you start.
Moskvich 2140 (1988) 1.5 UZAM-412DE: Alternator Drive Belt Replacement and Tensioning
On the UZAM-412 engine, a single V-belt turns the water pump with its fan and the alternator from the crankshaft pulley. Tension is adjusted by moving the alternator on its bracket with the adjusting strap. A belt that has broken or is slipping leads to a discharged battery and engine overheating, because the water pump stops turning as well.
Part
| № | Part |
|---|---|
| 01 | V-belt for alternator and water pump drive, UZAM-4121 pc |
Tools
4- Set of open-end and box-end wrenches (typically 13, 17, 19 mm)
- pry bar or small mounting bar for pulling the alternator out
- ruler
- shop rags
Step by step
11 steps- Park the car on level ground, set the parking brake, shut off the engine and let it cool down. For convenience, disconnect the negative battery terminal.
- Inspect the old belt for cracks, delamination, oily or "glazed" sidewalls, and torn chunks. Note how it runs around the crankshaft, water pump and alternator pulleys.
- Loosen the nut or bolt that secures the alternator to the lower mount (the bracket pin) and the bolt that secures it to the adjusting strap. You don't need to remove them completely; the alternator just needs to move freely.
- Push the alternator toward the engine to slacken the belt, and take the belt off the alternator pulley first, then off the water pump and crankshaft pulleys. If the belt won't come off, turn it by hand together with the pulley as it goes, and don't pry it off with a screwdriver.
- Inspect the pulleys: the grooves should be clean, with no rust, scoring or oil. Check for radial play on the water pump pulley and the alternator by rocking the pulleys by hand. Play means a worn bearing, and a new belt won't last long.
- Install the new belt on the crankshaft pulley first, then the water pump pulley, and the alternator pulley last. Make sure the belt sits in the grooves of all the pulleys.
- Pull the alternator away from the engine with a pry bar, resting it against the alternator housing (not the thin cover or the rotor), and tighten the adjusting strap bolt.
- Check the tension. Press with your thumb at the middle of the longest span between the alternator and water pump pulleys: the deflection should be about 10-15 mm with a force of about 10 kgf (about 22 lbf). A belt that is too tight quickly ruins the alternator and water pump bearings, and one that is too loose slips and squeals.
- Do the final tightening of the alternator mounting nut and the strap bolt. The torque is not critical for fasteners of this size: tighten them firmly without stripping the threads, roughly in the range of 20-40 N·m (15-30 lb-ft) (M8-M10 threads).
- Reconnect the battery terminal, start the engine and let it run for a few minutes. Listen: there should be no squealing. Rev the engine and make sure the charging warning light goes out.
- After 100-200 km of driving, recheck the tension: a new belt stretches and most often needs to be tightened.
Common mistakes and warnings
- Work with the engine off, and never put your hands between the belt and the pulleys while the engine is running
- If the belt breaks while driving, don't keep driving: the pump isn't circulating coolant, and the engine will overheat quickly
- Check the belt for oil leaks, because an oily belt slips, and in that case you must first fix the leak (crankshaft seal)