TM 5-3805-290-23-1
FUEL SYSTEM TESTS, INSPECTIONS, AND ADJUSTMENTS - CONTINUED
0011 00
CYLINDER BALANCE TEST - CONTINUED
2.
Listen for change in engine idle speed or for idle to become more erratic.
a.
If change occurs, tighten fuel line and go to step c.
b.
If no change occurs, this cylinder is misfiring.
c.
Repeat steps a and b for each cylinder to be tested.
d.
Record results of test and refer to Fuel Injector Nozzles Replacement (WP 0163 00) to test nozzles in question.
FUEL QUALITY TEST
0011 00
1.
Determine if water and/or contaminants are present in fuel by checking water separator (TM 5-3805-290-10).
N OT E
A full fuel tank minimizes potential for overnight condensation.
2.
Drain water separator, if necessary (TM 5-3805-290-10).
N OT E
Water separator can appear to be full of fuel when water separator is actually full of water.
3.
Determine if contaminants are present in fuel by removing sample of fuel from bottom of fuel tank.
N OT E
Color of fuel is not necessarily an indication of fuel quality. However, fuel that is black, brown, and/or simi-
lar to sludge can be indication of bacteria or oil contamination. In cold temperatures, cloudy fuel indicates
that fuel may not be suitable for operating conditions.
4.
Visually inspect fuel sample for contaminants.
5.
Check fuel API with Calibration fluid and diesel fuel test kit (Item 22, WP 0205 00). Acceptable range of fuel API is 30
to 45 when API is measured at 60F (15C), but there is significant difference in energy within this range.
N OT E
The measured fuel API rating and corresponding temperature must be corrected to 60F (15C) before
selecting fuel correction factor. Use Table 1 to determine fuel API rating at 60F (15C).
A correction factor greater than 1.000 may be the cause of low power and/or excessive fuel consump-
tion.
Table 1. Fuel Density (API).
API at 60F (15C)
Correction Factors
32.0
0.987
35.0
1.000
40.0
1.022
45.0
1.044
6.
If fuel quality is still suspected as possible cause of problems regarding engine performance, disconnect fuel inlet line
from tank (WP 0035 00), and temporarily operate engine from source of fuel known to be good. This will determine if
problem is caused by fuel quality.
