Leakage test.

TM 10-3930-673-34

(a)

Connect injector (1) to fuel injector

test set.

FUEL INJECTOR

(b)

Open valve and operate pump lever

TEST SET

at a rate of one stroke per second

while observing test pressure gauge.

VALVE

(c)

Spray must begin at a pressure of

3553 73 psi (24497.94

503.34 kPa).

(d)

Check for well atomized spray

pattern.

TR00785

(2)

Leakage test.

(a)

Use same test setup as for opening pressure test (Step (1) above).

(b)

Open valve on test set.

(c)

Operate pump lever as necessary to hold pressure at a level about 290 psi (1999.55 kPa) below

opening pressure noted in Step (1)(c) above.

(d)

No drops must fall from nozzle tip for a period of 10 seconds, while maintaining pressure

specified in Step (c), above. If drops do appear within 10 seconds, replace injector.

(3)

Chatter test.

(a)

Use same test setup as for opening pressure test (Step (1) above).

NOTE

Do not evaluate used nozzles at lower pumping rates. A used nozzle is serviceable if it

passes the leakage test, chatters audibly at higher pumping rates and uniformly

atomizes fuel.

(b)

Operate pump lever at a rate that causes nozzle to chatter softly while discharging fuel in a

broad and finely atomized pattern. If conditions of prior note are not met, replace nozzle.

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