Figure 3-28. Cleaning fuel injector nut spray tip seat.

TM 10-3930-242-34

Figure 3-28. Cleaning fuel injector nut spray tip seat.

h a n d l e several times, then hold the pressure at

1,500 psi for 15 seconds, Inspect spray tip seat

for leakage. If the spray tip seat is satisfactory,

proceed to check the hold time for pressure drop

of from 1,500-to 1,000-psi in less than 5 seconds;

replace needle valve and tip assembly if the hold

time is less than 5 seconds,

g. Lapping Injector Parts.

(1) Clean the lapping blocks with compres-

sed air,

(2) Spread lapping powder (600 grit (dry)) on

one of the lapping blocks.

( 3 ) Place the part to be lapped flat on the

Figure 3-29. Fuel injector sealing surfaces that may require

block, and using a figure eight motion, move it

lapping.

back and forth across the block using just