Installation of the Electronic Unit Injector
Perform the following steps: ?

If the fuel system is contaminated with coolant:
Drain the fuel tanks and refill with clean fuel.
Replace both filters with new, and clean the fuel/water separator, if equipped.
Inspect fuel injectors for damage and replace as required.
If the coolant system is contaminated with fuel, flush and reverse flush the system.
Using clean compressed air, blow out any fuel remaining in the injector bore.
Detroit Diesel encourages the use of an additional service seal (5104701) that is impervious to both coolant and fuel. This seal should be used in situations where injector tube seal leakage or deterioration is suspected or confirmed. Place the auxiliary seal in the injector hole and seat it against the top of the injector tube with a 41.3 mm (1-5/8 in.) diameter wood or plastic dowel.
Check to make sure the injector bore is thoroughly clean.
Apply a thin coat of clean ethylene glycol to the injector seal rings and install them in the injector nut ring grooves. Make sure seals are properly seated.
Insert the injector into its respective injector tube bore. Visually align the injector body for equal clearance between valve springs (there is no locating dowel pin on the underside of the EUI). After locating the injector, press down on the top of the injector body with the heel of your hand to seat it in the injector tube.
Determine which type of hold-down crab is used by measuring the overall height.