Cam Pulley Wobble

[Softlad 2]

A friend is rebuilding an E36 318 standard auto after having the head rebuilt.

We were in the process of putting it back together today and noticed as we were about to do the timing belt that when you slot the cam pulley onto the end of the cam, there is a small notch on the internal radius of the pulley that has to line up with a recess in the end of the cam.

Once slotted together there is almost 2 timing belt teeth backwards & forward movement as the notch wobbles about in the slot.

Should there be a spacer or jacket of some kind that centrally positions the cam pulley notch into the slot on the cam, because as there is just a single bolt securing this in place at the axis as soon as the engine is started it's going to slip.

Please advise

[williams 0]

when doing time belt on m40 engines and u have loosened the pulley the cam timing needs to be set again, put the crank on top dead centre,make sure the cam is rocking on cylinder 1 or 4 (there is a square on the front of cam) make sure it is level with the head,tension up the cambelt and lock it. then u can lock the cambolt,be sure to turn the motor 360 deg to recheck timing marks-this is done so that the cam timing will always be 100%

[*Glenn* 854]

You need special tools to lign up the timing correctly. You can guess or take pot luck with it , however it wont be right and could effect performance and / or idle

[bravo 34]

So the m40 has an adjustable cam pulley?? Or the key on the cam and the notch on the puley are worn?

[Silver Fox 43]

It has a little adjustment each way Graham.

One tooth out equated to around 5 hp on our car. Makes a big difference, about 4 secs at Puke.

[Silver Fox 43]

You need special tools to lign up the timing correctly. You can guess or take pot luck with it , however it wont be right and could effect performance and / or idle

Tools are easy to get thru Ebay, or you can make your own which work just the same. As Glenn says, it makes a big difference.