This noise is said to come from the cams due to incorrect valve setup ( when setting valve clearance each cylinder must be set to TDC ) or from age and use of incorrect oil grade.
12.
It was de-tuned in the US with twin Strombergs and larger valve clearances, but in the UK retained triple SUs and the much tighter valve clearances . ( Series 1?cars also had ribbed cam covers ).
13.
The hydraulic lifter was designed to compensate for this small tolerance, allowing the valve train to operate with zero clearance leading to quieter operation, longer engine life, and eliminating the need for periodic adjustment of valve clearance.
14.
It was de-tuned in the US with twin Strombergs and larger valve clearances, but in the UK retained triple SUs and the much tighter valve clearances . ( Series 1?cars also had ribbed cam covers ).
15.
To flow more air, the head was revised extensively from the earlier model, featuring new ports, a'bathtub'combustion chamber borrowed from their own S2 racer, and a 1mm larger intake valve recessed into the head slightly for valve clearance.
16.
At the same time, higher gearing and reduced valve clearances cut the published power output by 2 bhp but cured the " valve-crash " reported by some buyers when approaching top speed on one of Britain's recently constructed motorways.
17.
In a typical application the helical camshaft would have a continuous duration range from about average for a road-going general purpose engine ( about 250 degrees measured at normal valve clearance ) to about 100 or 150 degrees above this.
18.
But actually reading the manual and the maintenance guide, you come to find out that ball joints need to be checked for looseness, and dust covers for deterioration, engine valve clearance for excessive filter noise and the fuel tank cap gasket for cracks.
19.
The wasserboxer, as with all Volkswagen boxer engines, directly drives the three-bearing camshaft via a small steel gear on the crankshaft, and a large aluminium one on the camshaft, so there is no springs, and are operated by pushrods, with adjustable rocker arms to facilitate valve clearance adjustment.
