GOOD OIL

NZ Truth, Issue 1136, 8 September 1927, Page 13

GOOD OIL

\ About Decarbonizing ! The Engine In the case of some extremely ) hot running engines, carbon may > form on the upper part of the small end of the connecting rod where it will block the oil-ways which are I provided, and lead to their seizing. > It is advisable therefore when de- ; carbonizing an engine, to remove i the gudgeon pins' and make sure » that all is m order. WITH engines which have detachable cylinder heads, it is not always easy to decarbonise the under-sides of the piston, but it would he lair to say I that for every three times that the t combustion chamber is decarbonized s the under-side of the piston should be [ done once. i In hilly districts carbon formation is 'generally more rapid than m flat districts. When a car is descending a hill with the throttle closed, the partial vacuum above the pistons on each suction stroke causes oil to be sucked past the piston rings, evidence of which :s given by nearly every car when it is opened out after descending a hill, the "evidence" taking the form of a trail of blue smoke from the exhaust, caused, of course, by burnt oil. An engine which is often idling m traffic also carbonizes rapidly as slow running tends to draw oil into the combustion chamber. Carburettors usually provide a rich fuel mixture which tends towards increased deposit. The motorist Avho wishes to avoid carbon should — 1 Run on a weak mixture as far as possible, avoid conditions leading to ! overheating, avoid taking m dusty air 1 for combustion by installing an air L cleaner, and make sure that lubricating ! oil is kept down as much as possible by '■ piston rings that are effective. 1 Use only the best brands of oil, and see that the grade used is correct for the particular engine [ m which it is employed.