TM 5-3895-383-24
Pressure Test Location
(1) Plug.
The 1U5470 Engine Pressure Group has a gauge to read
pressure in the inlet manifold. Special Instruction, SEHS8524,
is with the tool group and gives instruction for its use.
Exhaust Temperature
Tools Needed
1U8865
Infrared Thermometer
1
Use the 1U8865 Infrared Thermometer to check exhaust
temperature. The Operators Manual, NEHS0510, for the
1U8865 Infrared Thermometer gives complete operating and
maintenance instructions for this tool.
Engine Blow-By (Air Flow)
Tools Needed
8T2700
indicator Group (Engine Blow-By/Air Flow)
1
Pistons or rings that have damage can be the cause of too
much pressure in the crankcase. This condition will cause the
engine to run rough. There will also be more than the normal
amount of fumes (blow-by) coming from the crankcase
breather. The breather can then become restricted in a very
short time, causing oil leakage at gaskets and seals that would
not normally have leakage. Other sources of blow-by can be
worn valve guides or turbocharger seal leakage.
8T2700 Indicator Group
The 8T2700 Indicator Group is used to check the amount of
blow-by. The test procedure is in Special Instruction,
SEHS8712.
Compression
An engine that runs rough can have a leak at the valves, or
have valves that need adjustment. Removal of the head and
inspection of the valves and valve seats is necessary to find
those small defects that do not normally cause a problem.
Repair of these problems is normally done when reconditioning
the engine.
Cylinder Head
The cylinder head has valve seat inserts, valve guides and
brass sleeves that can be removed when they are worn or
have damage. Replacement of these components can be
made with available service tool groups that are referred to in
the Disassembly And Assembly procedure, SENR3611.
Valve Lash
Valve lash is measured between the rocker arm and the valve.
All lash measurements and adjustments must be made with
the engine stopped, and with the valves FULLY CLOSED.
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