At every engine overhaul you have to replace all bearings, including the camshaft bearings.
Only since August 1965 Volkswagen uses camshaft bearings, before that the camshaft was mounted in the crankcase without bearings. at that time, it was normal for an engine to need an overhaul rather quickly. The life of the engine was extended considerably when Volkswagen decided to run the camshaft in bearings.
With the use of dual valve springs, but even with heavier valve springs, the lateral forces on the camshaft are much greater, resulting in higher than normal wear on the bearings and crankcase. To avoid this, you can equip Type 1, Type 3 and CT/CZ engines with so-called "double trust" camshaft bearings, which Volkswagen has used as standard on water boxer (WBX) engines and the latest Mexican Type 1 engines. Double trust camshaft bearings have a raised edge on both halves of the bearing, instead of just one side of the bearing. This allows more pressure to be applied to the camshaft without further damaging it. Please note that a small modification to the housing is required for this.
Oversized camshaft bearings are mainly found on engines that were overhauled by Volkswagen at the time, which can be recognized by the deeply milled engine number. For the assembly we recommend the use of an assembly paste, which ensures good lubrication during the running-in process and prevents premature wear (see tab `Options`).
Please note: In most cases you will need standard bearings, but always measure before ordering. Please note that once the packaging of the camshaft bearings is opened, no returns are possible.
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