Vanadium in the fuel causes high temperature corrosion and cannot be removed in any pretreatment processes. Vanadium combines with sodium and sulphur during combustion process and form eutectic compounds with melting point as low as 530 degree celcius and react with protective oxide layer on steel and corrode them. they also can cause metal ash deposits in valves.The only defense is to reduce the working temperatures and coat critical parts prone to this corrosion with stellite or plasma coatings.
Since very small needle lift is obtained in the test equipment result in an unequal pressure distribution in the cut off shaft resulting in a hard contact in a small area along with high frequency oscillations, low lubricity of test oil will increase the chance of seizure. Full lift and high lubricity of heavy oil eliminates this risk of seizure during normal operation.( Always open and clean slide type valves before testing as cold sticky heavy oil along with small clearances can cause restriction in the movement of the spindle).
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