DETROIT DIESEL 53
15.2 Trouble Shooting (Engine)
fuel and the fuel pipes rid of air in order for the
system to provide adequate fuel for the injectors.
When an engine has run out of fuel, there is a definite
procedure to follow for restarting it:
1. Fill the fuel tank with the recommended grade of
fuel oil. If only partial filling of the tank is possible,
add a minimum of ten gallons of fuel.
and record the compression pressure indicated on the
2. Remove the fuel strainer shell and element from the
page. Do not crank the engine with the starting, motor to
strainer cover and fill the shell with fuel oil. Install the
obtain the compression pressure.
shell and element.
6. Perform Steps 2 through 5 on each cylinder. The
3. Remove and fill the fuel filter shell and element
compresston pressure in any one cylinder at a given
with fuel oil as in Step 2.
altitude above sea level should not be less than the
minimum shown in Table 1. In additon, the variation
4. Start the engine. Check the filter and strainer for
in compression pressures between cylinders must not
leaks.
exceed 25 psi at 600 rpm.
NOTE: In some instances, it may be necessary to
remove a valve rocker cover and loosen a fuel
pipe nut to bleed trapped air from the fuel
system. Be sure the fuel pipe is retightened
securely before replacing the rocker cover.
Primer J 5956 may be used to prime the entire fuel
system. Remove the filler plug in the fuel filter cover
and install the primer. Prime the system. Remove the
primer and install the filler plug.
Fuel Flow Test
The proper flow of fuel is required for satisfactory
engine operation. Check the condition of the fuel
pump, fuel strainer and fuel filter as outlined in
Low compression pressure may result from any one of
Section 2.0 under Trouble Shooting.
several causes:
A Piston rings may be stuck or broken. To
Crankcase Pressure
determine the condition of the rings, remove the
air box cover and inspect them by pressing on the
The crankcase pressure indicates the amount of air
rings with a blunt tool. A broken or stuck ring will
passing between the oil control rings and the cylinder
not have a "spring-like" action.
liners into the crankcase, most of which is clean air
from the air box. A slight pressure in the crankcase is
B. Compression pressure may be leaking past the
desirable to prevent the entrance of dust. A loss of
cylinder head gasket, the valve seats, the injector
engine lubricating oil through the breather tube,
tube or a hole in the piston.
crankcase ventilator or dipstick hole in the cylinder
block is indicative of excessive crankcase pressure.
Engine Out of Fuel
The causes of high crankcase pressure may be traced
to excessive blow-by due to worn piston rings, a hole
The problem in restarting an engine after it has run
or crack in a piston crown, loose piston pin retainers,
out of fuel stems from the fact that after the fuel is
worn blower oil seals, defective blower, cylinder head
exhausted from the fuel tank, fuel is then pumped
or end plate gaskets, or excessive exhaust back
from the primary fuel strainer and sometimes partially
pressure. Also, the breather tube or crankcase
removed from the secondary fuel filter before the fuel
ventilator should be checked for obstructions.
supply becomes insufficient to sustain engine firing.
Check the crankcase pressure with a manometer
Consequently, these components must be refilled with
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