A CURIOUS TROUBLE

Shannon News, 21 August 1928, Page 4

A CURIOUS TROUBLE

An engine was recently taken down for decarbonising and valve-grinding. After everything had been cleaned in kerosene, the valves ground in, and the parts reassembled, the engine was

. run for a short time in order to get f the correct tappet adjustment with the cylinders warm. On the first journey out it was noticed that the tappets became noisy at certain periods, after which the noise would stop. The engine was stopped during one of the times that the tappets were noisy, and,

on examination, it was 4 found that those of No. 1 inlet and No! 3 exhaust had twice as much clearance as had-been given to them previously. However, they were again adjusted to the correct distance. It was then found that at times there was blowing past the valves, showing that the clearance was not sufficient. Eventually the tappets with thpir guides, were removed, and it was discovered that the roller pins were badly worn and that they were being forced round in the pushrods by the i oilers so'that sometimes the worn part of any particular pin was at the top, thus dotting the tappets drop lower, whilst at other times it was at the bottom, and the tappets were returned to their proper- position. w A cure was effected by fitting new roller pins.