TM 5-3895-346-14
INJECTOR TUBE
ENGINE OVERHAUL
FUEL INJECTOR TUBE
The bore in the cylinder head for the fuel injector is directly through the cylinder head water jacket as shown in
Fig. 1. To prevent coolant from contacting the injector and still maintain maximum cooling of the injector, a
tube is pressed into the injector bore. This tube is sealed at the top with a neoprene ring and upset into a flare
on the lower side of the cylinder head to create water-tight and gas-tight joints at the top and bottom.
Remove Injector Tube
When removal of an injector tube is required, use injector tube service tool set J 22525 as follows:
1. Remove, disassemble, and clean the cylinder head as outlined in Cylinder Head.
2. Place injector tube installer J 5286-4 in the injector tube. Insert pilot J 5286-5 through the small opening of
the injector tube and thread the pilot into the tapped hole in the end of the installer (Fig. 1).
3. Tap on the end of the pilot to loosen the injector tube. Then lift the injector tube, installer, and pilot from the
cylinder head.
Install Injector Tube
Thoroughly clean the injector tube hole in the cylinder head to remove dirt, burrs, or foreign material that may
prevent the tube from seating at the lower end or sealing at the upper end. Then install the tube as follows:
1. Place a new injector tube seal ring in the counterbore in the cylinder head.
2. Place installer J 5286-4 in the injector tube. Then insert pilot J 5286-5 through the small opening of the
injector tube and thread it into the tapped end of the installer (Fig. 2).
Figure 1. Removing Injector Tube.
Figure 2. Installing Injector Tube.
240
