DETROIT DIESEL 53
GEAR TRAIN AND ENGINE TIMING
A train of helical gears, completely enclosed between the engine end plate and the flywheel housing, is located
at the rear of the Series 53 engines.
The gear train on an In-line engine (Fig. 1) consists of a crankshaft gear, an idler gear, a camshaft gear, and a
balance shaft gear. The governor drive gear, the upper blower rotor gear for the three cylinder engines, are
driven by the camshaft gear or balance shaft gear, depending upon the engine model.
On In-line engines, the crankshaft gear is pressed on and keyed to the end of the crankshaft.
The idler gear rotates on a stationary hub.
The camshaft and balance shaft gears on In-line engines are pressed on and keyed to their respective shafts
and each gear is secured by a retaining nut and lock plate.
The crankshaft, idler, camshaft and balance shaft gears on In-line engines are completely interchangeable with
On In-line engines, the camshaft and balance shaft gears have additional weights attached to the rear face of
These weights are important in maintaining perfect engine balance.
Figure 1. In-Line Engine Gear Train Timing Marks (Standard Timing Shown)
February, 1972 SEC. 1.7.1 Page 1