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Tools - Diesel Timing Meter Damage

Number 83-I-46 Section 6B Date 03/83
Subject: DIESEL TIMING METER
Snap-On Corporation advises that luminosity probes are being damaged by being overtorqued in the cylinder head. This cracks the quartz and allows soot to get behind the lens where it cannot be cleaned. In some cases, meters have been returned for repair when only the probe was at fault. Before the probe is used, hold it up to the light to make sure it is clear. When installing the probe in the cylinder do not exceed the torque specification of 11 N-m (8 ft.lbs.).