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Crankshaft Group - Removing and Installing the Cam Belt Idler

13-509 Removing and installing cam belt idler

The idler roller serves to increase the number of teeth on the cam sprocket that actually engage the cam belt. It is absent on early vehicles although there is provision for fitting it and a retrofit of the later system (longer belt) is easy. If this is desired, expert advice should be sought and careful notes should be made in the service documents.
The bolt does not retain the roller and must not be used to pull it into place. It is merely an oil pump retaining bolt that just happens to be there.
Service tool 3034 is highly recommended. In an emergency, the roller can be removed using extreme care and one or more large screwdrivers - take great care not to damage the interference fit.
The replacement roller should be driven home with a drift. Before doing so, check its diameter against the old one - it is possible (just) to fit the larger version in place of the smaller one, but this may seriously damage the front cam bearing - since the cam is line-bored, this scraps the cylinder head.