METHOD FOR THE DETERMINATION OF THE COMPOSITION OF DIESEL-ENGINE PISTON DEPOSITS BY INFRARED-SPECTROSCOPY

A chemical method for separating diesel engine piston deposits into va rious organic and inorganic components is described, The components ar e subsequently analyzed by infrared spectroscopy, The method is illust rated with examples of deposits removed from the upper lands and upper ring grooves of pistons taken from heavy-duty diesel engine tests, Su btle chemical differences were observed between two deposits removed f rom upper lands of pistons taken from diesel engine tests which had be en carried out with the use of lubricating oils with different formula tions, More obvious differences were found between the deposits taken from the upper land areas and the upper ring grooves, These results in dicate that a combined chemical and spectroscopic approach has the pot ential to provide detailed chemical information about engine deposits.