Some Notes on the Six-cylinder Buick.
Page 10
If you've noticed an error in this article please click here to report it so we can fix it.
THE Buick with the six-cylinder engine is now being used to a fair extent for the lighter classes of commercial work. Therefore, the following notes should prove useful.
Incorrect assembling of one or two of the connecting rods and pistons can easily be the cause of irregular running, particularly at slow speeds. This fault is sonaetimes difficult to trace.
As in some other compactly built engines, the connecting rods are offset in relation to the crankpin, and when replacing them care should be taken to See that in each the forging number in the clan pel of the rod is so set in relation to the adjacent main bearings that the smooth channels of the rods face each other in pairs between the main bearings.
A peculiarity of the engine—and this, we believe, also applies to the four-cylinder model—is that the gudgeon pins are also offset, in relation to the vertical centre line of each piston, to quite a considerable extent, as shown in the diagram. great care must, therefore, be exercised when replacing a piston or fitting a new one, in order that the gudgeon pin be offset towards the near side of the engine.
When a piston is examined for the first time, the position of the gudgeon-pin holes might lead one to believe that the machining is at fault, but if the diagram be studied it will be seen that the effect of this offset is the same as if the cylinders themselves had been offset in relation to the crankshaft axis.
A knock which is somewhat difficult to trace can sometimes be heard in the engine of a six-cylinder Buick chassis running slowly. It sounds very much like a slight big-end or gudgeon-pin knock, but it is advisable, before dropping the sump or dismantling any other parts, to try tightening or repacking the glands of the water-circulating pump. If doing so stops or alters the period of the knock, it may be assumed that there is a little end play on the pump-shaft bearing which requires to be taken up.