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Engine guides and mods

Forfour Belt Tensioning

How to adjust the belt tension via the alternator.

Modification Details

Is your poly belt making a squealing noise? it's probably not tight enough.

Tighten The Belt

Remove the decorative engine cover to gain better access.
Check the belt for obvious signs of wear or damage.

Ensure the keys are in your pocket.
You don't want someone accidentally starting the car with your hands in the engine.
It'll pull you in, flap you around like a rollerblind and spit you out with no skin on.

Over on the left is the alternator and its associated belt.
Below its main pulley wheel is the pivot bolt, loosen this nut by 1 turn.


On top of the alternator are another 2 fixings. The nut circled yellow below is the adjustement lock
bolt. Loosen this adjustment lock bolt by 1 turn. The final fixing circled in green is the adjuster bolt.

Turn this bolt half a turn clockwise to see if it has rectified the problem, if not, give it another.
Don't go too mad and don't be tempted to do this with the engine running.

This bolt should probably be torque to a particular setting but at present I don't have that info.
Don't over tighten as this can cause damage to the alternator and pulley bearings. 

When you are happy that the belt is tensioned properly (or better than it was), retighten
the other 2 nuts, start and rev the engine a bit, turn off and replace the engine cover.

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