Snap-On Diagnostics DGA 1000, Руководство пользователя

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Vehicle Testing Procedures
6-13
Fuel Leak Test
The analyzer is extremely sensitive to fuel vapor, even at relatively
low concentrations. Use this test to find leaks in fuel system
components long before the liquid fuel is visible. Any part of the
fuel system can develop leaks, but common leakage areas include:
•
Mechanical fuel pump vent holes,
•
Charcoal vapor storage canister,
•
Fuel filler cap,
•
Fuel lines, and
•
Fuel tank seams, flanges and rusty areas.
Testing Tips
X
Gasoline fumes are heavier than air. Keep the probe on the
lowest side of the area being tested when searching suspected
leak areas.
X
Air stream in the immediate area may affect test results. Shield
the probe from wind draft or stop the engine when testing near
a running engine. Small leaks may require testing after a
stabilization period in a breeze-free location.
Test
1. Hold the sample probe near suspected leak areas.
Do not put the probe in direct contact with the fuel
or allow it to draw liquid into the sampling system.
Fuel contamination of the sampling system ruins
analyzer accuracy and can cause damage to the
system.
✓
When working near a running engine, shield the probe
from drafts or stop the engine if possible to avoid vapor
contamination from other areas.
2. Note the HC reading.
Interpretation
•
HC readings above baseline < 10 ppm HC traces indicate fuel
leakage.