Answer
Aug 21, 2025 - 07:19 PM
Adjusting the alternator belt on an L300 isn’t exactly rocket science, but you’ll wanna do it right so it doesn’t squeal or slip later. Here's how:
- Pop the hood and disconnect the battery. Always start with that just to be safe.
- Find the alternator. It's usually on the side of the engine with the belt running over it.
- Loosen the bolts. There’s one at the bottom (pivot bolt) and another up top (the adjustment bolt). Don’t take ‘em out — just loosen them enough so the alternator can move.
- Adjust the belt.
- If it's loose and you’re tightening it, pull the alternator away from the engine — use a pry bar if needed.
- If you're loosening it, just push it in a bit.
- Check the tension. Press the middle of the belt — you want around 10mm of play (give or take). Not too tight, not too floppy.
- Tighten the bolts back down. Start with the adjustment bolt, then lock in the pivot bolt.
- Reconnect the battery and fire it up. Listen for squeals. If it still makes noise, belt might be too loose — or too tight, which isn’t great for the bearings either.
If the belt looks cracked or shiny, do yourself a favor and just throw a new one in.
Of course, that's just the general idea of it. A more detailed and accurate procedure will be covered in the service manual, though. Perhaps if you could let us know more details about your L300, we'll be happy to point you to the right manual that suit your needs.
