On Type 1 engines up to September 1992, the oil is only filtered with the filter behind the sump plate. It was only in October 1992 that Volkswagen finally replaced it with a much better filtration system, with a modern filter mounted behind the oil pump. Type 3 engines never even had that as standard.
On CT/CZ, Type 4 and water-cooled engines, this improved filtration system is applied directly, not to the oil pump, but as on all modern cars against the crankcase. It is incomprehensible that it should have taken so long for Type 1 engines, the sieve behind the crankcase cover only retains coarse dirt, whereas clean engine oil is so important for an air-cooled engine, it is not only a lubricant but also helps to cool the engine.
If you want to filter the oil better, this external support is a godsend. It can be mounted between the oil lines of an external oil cooler, for example, or if you do not have an external oil cooler, using a filter flow oil pump.
You can also use your existing oil pump with a suitable oil pump cover equipped with an additional flow rate. With a filter flow oil pump, the oil passes from the pump through the filter and back to the oil pump. If the cover is loosened, the oil is fed to the filter, where it is pumped back through the main channel. For the latter option, the main oil channel must be drilled and equipped with a return hose adapter.
This adaptor is available with the inlets and outlets facing left or right, this is just where you want to mount the adaptor and how you end up with the oil hoses.
Comes without oil filter and connections, take it extra if necessary (listed on the tab options)
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