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Old 27th January 2010, 07:25 PM
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Davey Davey is offline
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Default ZETEC timing gear fixing.

Hi all, just a brief note really to anyone intending on using a second hand Zetec motor regarding securely fixing the timing pulleys. As anyone who has worked on these engines will know the pulleys are all clamped in place by the centre bolts (both camshafts and the crank pulley) with no positive location like a keyway.

I know from personal experience that the bottom pulley bolt can come loose, especially if not loctited and torqued up to "FT" after a belt change) and if it does then your engine is likely to end up as scrap (unless you need a new anchor for a boat).

What I now do with these engines is to drill and tap to 4mm thread and fit a grub screw to provide positive location. The camshafts can be done axially (off centre obviously) through the centre boss face of the pulleys, the crank is a bit more tricky. For the crank pulley I drill in radially using an angle headed drill in the bottom of one of the teeth grooves and drill far enough to dimple the crankshaft itself. Make sure to throughly deburr the holes and remove all swarf.

I think this is only possible with the engine on the bench but my method is simple. This applies to engines out of a Focus, not sure about lumps from other models.

Remove the top engine mounting bracket and belt cover. Cut a piece of 50X50X3mm angle 26mm long and drill a 10mm hole through one face to line up with the engine mounting bolt hole the is below and central to the cam pulleys. you will probably need to grind a small notch into the holed flange on either side to clear the cam pulley teeth. This bracket can then be slotted between the teeth of the two pulleys and bolted to the head to lcok the cams in position.

At the flywheel end make a bracket out of angle iron or channel section to lock the flywheel (and therefore crankshaft) firmly in position.

Remove the bottom auxilliary belt pulley but leave the old belt on.

Now drill the bottom pulley as described above. Drill and tap the pulley centre bosses of the camshafts and fit 4mm grub screws adding a drop of loctite.

Now you can remove the belt and bottom timing pulley. Carefully tap the hole in the bottom pulley, then clean and deburr it.

Refit the bottom timing pulley lining the new tapped hole up with the dimple in the crankshaft and fit the grub screw with a drop of loctite.

Fit your new belt and tensioner and then you can remove your locking brackets.

open to comments, D.
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