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Hints for changing the engine pulleys on a MY03 WRX for CDF alloy ones.

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  • Hints for changing the engine pulleys on a MY03 WRX for CDF alloy ones.

    Power Steering pulley removal.

    1. Undo the two 10mm cover fixings.
    2. Lift the corner to release cover & swivel it out the way around the throttle cable.

    3. Spray some "Plus Gas" or "WD40" on the shaft & nut to be soaking in.
    4. Slacken the two 12mm bolts holding the alternator & turn the adjuster anti clockwise to slacken the belt enough to remove.

    5. Place a short extension bar through the pulley aperture & rest it on the ledge of the pump mounting bracket.
    6. Use a 19mm ring spanner to undo the pulley nut whilst bracing the extension bar against the ledge to gain leverage & stop the pulley turning.

    7. Remove the nut & slide the pulley off the splined shaft..

    Alternator pulley removal

    The alternator pulley is held on by a 24mm nut but has no openings to lock it against anything. Don't be tempted to poke something inside the alternator as you will damage it. Impact air wrench is probably easiest way to loosen it.
    I had a new Alternator fitted not long ago at a Subaru dealer & you can see four sets of clamp marks equally spaced around the edge of the pulley. This is where they clamped the pulley whist it was undone. A strap wrench, oil filter tool or pipe wrench would work.

    Crank pulley removal.

    The crank pulley has a 22mm nut & it can be undone by putting the car in 5th gear & putting the handbrake on to hold it. Foot brake can be used if needed as well. Watch for & collect the key in the keyway.

    Fitting Classic pulleys.

    These pulleys are the easiest to fit , simply remove old pulleys and replace with new ones then tighten bolt.

    Newage pulleys

    These pulleys are made to create a fine spline in the alloy as they are tightened onto the shaft.
    1) Remove old pulley.
    2) Spray the shaft with some WD40 or brush the shaft with some oil.
    3) Place the new pulley on the shaft. It will only go half way.
    4) Keeping the pulley square, place the nut back on. Tighten nut until pulley is drawn fully onto the shaft.

    Bugeye pulleys

    The bugeye pulleys are on a plain shaft (as shown)
    You will need a puller to remove the old pulley as they are pressed on.
    The new pulleys have a tapered bore - so it will start to go on the shaft at the back of the pulley.
    You may be able to tap the pulley flush onto the shaft but it is recommended that they are pressed on.

    Finally check the vee's line up when you put the belts back on.


    KEYWAYS in the crank pulleys have been made to the top limit , if you find any that are tight going on you will need to either tap down the key in the shaft or file a small bit of key out.
    All the keyways in the shafts are never spot on the same, that is why we have made the keys to the top limit , if we go too high we risk making the keyway too big if the shaft only has a shallow keyway.

    Fitting :- Disclaimer: This is for information only & does not claim to be complete & should not be interpreted as instructions. If in doubt seek qualified help.
    Last edited by Flat Eric; 12-02-11, 10:35 PM.