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Home >> Mercedes Benz >> 1987 >> 560SEC (126.045) V8-5.6L (117.968) >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Component Tests and General Diagnostics >> Component Tests >> Injection Valve Test
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Injection Valve Test


This Test Is Divided Into The Following Sections:

A. Valves without Viton Seals

B. Valves with Viton Seals

Special Tools:





Injection Valve Test
A. Valves without Viton Seals

Injection Valves Without Viton Seals:





Tightening Torque (without Viton Seals)
- Injection lines to fuel distributor (reference value)
^ 10-12 Nm (89-107 in. lbs.)
- Injection lines to injection valves (reference value)
^ 12 Nm (107 in. lbs.)

NOTE: Before testing injection valves, fill container of tester with clean test fluid (e.g. Shell Mineral Spirits 135) and bleed tester.

CAUTION!
^ Never use normal gasoline or other easily flammable/combustible fluids in valve tester.

^ Only injection valves which do not meet specifications must be replaced. Always install new seals when reinstalling the injection valves.

Test:





Injector Tester:





Damaged Injection Valves
- Evaluate On Valves Without Viton Seals Only!

Formation Of Drops:





Cord-like Jet:





Poorly Proportioned Jet:





Good Injection Valves
- Evaluate On Valves Without Viton Seals Only!

Well Proportioned Jet:





Slightly One-Sided Atomization:






Injection Valve Test
B. Valves with Viton Seals





Tightening Torque (with Viton seals)
- Injection lines to fuel distributor (reference value)
- 10-12 Nm (89-107 in. lbs.)
- Injection lines to injection valves (reference value)
- 12 Nm (107 in. lbs.)

NOTE:
^ Injection valves should be tested as soon as possible after removal from the engine (Viton seals will dry out and affect the opening pressure readings).

^ Before testing injection valves, fill container of tester with clean test fluid (e.g. Shell Mineral Spirits 135) and bleed tester.

CAUTION!
^ Never use normal gasoline or other easily flammable/combustible fluids in valve tester.

^ Only injection valves which do not meet specifications must be replaced. Always install new seals when reinstalling the injection valves.

TEST:





Fig. 1: