Usage:
Reference: Engine News, September 10, 1980, Pages 1 and 2.
In the article "4S6553 Engine Evaluation Test Instrument Group Has Been Canceled," you were told of problems with availability of this group at the source of supply. Replacement components of this test instrument group will be available until the current quantities are exhausted.
Owners of the 4S6553 Engine Boost Group can still use it, but it is Caterpillar's recommendation that it be used in non-critical applications. In critical applications the new 6V3121 Digital Multitach Group should be used along with the 6V3150 Low Pressure Group for speed adjustments. This new group has an accuracy of ± 1 RPM instead of ± 50 RPM with the 4S6553 Group.
The 4S6997 Dual Boost Gauge, 1P7443 Tachometer and 1P7444 Tachometer Generator can still be repaired by:
317 E. Lewis
Wichita, Kansas 67202
U.S.A.