TM 5-3895-383-24
1U6602 Tachometer Group (Photo-Tachometer)
The 1U6602 Tachometer Group is a hand held phototach for
general use. The 1U6602 Tachometer Group is a phototach
only and reads only the basic input frequency (one pulse per
revolution per piece of reflective tape) on any visible rotating
part. The 1U6602 Tachometer Group does not replace the
6V3121 Multitach Group.
Special Instruction, SEHS8854 is with the 1U6602 Tachometer
Group and gives instructions for its use.
9S8140 Cooling System Pressurizing Pump Group
9S8140 Cooling System Pressurizing Pump Group
The 9S8140 Cooling System Pressurizing Pump Group is used
to test pressure caps and to pressure check the cooling system
for leaks.
DO NOT loosen the filler or pressure cap on a hot engine.
Steam or hot coolant can cause severe burns.
Checking Pressure Cap
Tools Needed
9S8140
Cooling System Pressurizing Pump Group
1
One cause for a pressure loss in the cooling system can be a
bad seal on the radiator pressure cap.
Typical Schematic Of Pressure Cap
(A) Sealing surface of cap and radiator
DO NOT loosen the filler or pressure cap on a hot engine.
Steam or hot coolant can cause severe burns.
After the engine is cool, loosen the pressure cap and let the
pressure out of the cooling system. Then remove the pressure
cap.
Inspect the pressure cap carefully. Look for damage to the
seal or to the surface that seals. Any foreign material or
deposits on the cap, seal or surface that seals, must be
removed.
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