How do you prevent camshaft rotation when you install or remove a camshaft pulley? (such as when you want to replace a camshaft seal or timing belt). There are many procedures for locking camshaft pulley like using a variety of cam pulley holders. However, when you tighten cam pulley bolt, the camshaft itself may move due to the high friction of the bolt and that will make cams off their timing marks. One method is to remove valve covers and hold the camshaft with a wrench but I don't want to use this trick so please suggest other ways to do it.

Peugeot 406 1.8 16V (XU7JP4 LFY)

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  • To generate a specific idea for your vehicle, it'd help to know what motor you're working on. Jun 27, 2021 at 15:08
  • @DavidSupportsMonica - I added a picture of my engine as an example. Jun 27, 2021 at 15:20

1 Answer 1


Most pulleys are designed with holes that have pins or bolts put through them into the head.

Or there are vernier pulleys to get the cam precisely rotated into position.

Some cams have machined flats to be held with a soecial bracket so the cam is located correctly. NOT designed for a wrench as you suggest.

One engine we dealt with had issues of smoke and a 1/2 degree adjustment sorted it.

Based on the info added, the manual suggests either the sprocket locking tool or making one, both do not use the timing holes.


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