Usage:
3208 Truck Engines ( 2Z)
The basic engine arrangements for 3208 Truck Engines (2Z) have been changed for 1985. The changes have been made so the engines will meet 1985 emission requirements. The changes include new governor and fuel injection pump groups. Also changed are the piston and rod groups, turbocharger groups and fuel pump drive groups on some engines.
The new governor and fuel injection pump groups have new fuel injection pump assemblies. The new parts are shown in Charts A and B.
Illustration 1. Orificed delivery valve (ODV).
The fuel injection pump assemblies have an orificed delivery valve (ODV). See Illustration 1. In the past, pump assemblies used a reverse flow check valve (RFC) as shown in Illustration 2.
Illustration 2. Reverse flow check valve (RFC).
The new ODV performs the same functions as the RFC with fewer parts. They both give protection against continuous fuel flow from the fuel transfer pump to the cylinder caused by a cracked or broken fuel injection nozzle. Both (ODV and RFC) bleed the fuel pressure pulses, that occur between injections, back to the fuel transfer pump.
The static timing for the fuel pump and governor groups used in these engines is shown in Chart C.
Some engine arrangements use new governor and fuel injection pump drive groups. The new drive groups have a different timing advance than the former drive groups. See Chart D.
The new fuel lines groups contain new fuel lines and new fuel injection nozzles. The new fuel lines have a larger inside diameter of 1.83 mm (.072"). The part numbers for the new fuel lines are shown in Chart E. The new fuel lines can be identified by notches on the nuts used in the fuel line assemblies. An example of the notched fuel line nut is shown in Illustration 3.
Illustration 3. Notched nuts used on new fuel lines.
A new 4W7016 Fuel Injection Nozzle Assembly is used in the turbocharged 3208 Truck Engine for 1985. See Illustration 4.
Illustration 4. New 4W7016 Fuel Injection Nozzle Assembly.
Fuel enters the new fuel injection nozzle assemblies from the top. See Illustration 4. The fuel line on the new fuel injection nozzle assembly is formed to go over the top of the rocker shaft of the valve mechanism. This will allow the fuel injection nozzle assemblies to be removed without removing the rocker shaft.
NOTE: The line assembly and adapter must not be removed from the nozzle assembly.
Some engine arrangements have replaced their former high compression ratio (18.2:1) rod and piston groups with lower compression ratio (17.5:1) rod and piston groups. See Chart F.
Chart G shows the new turbocharger groups used in the new engines.
The model year of the engine is listed on the emissions decal on the valve cover. The engine or engine parts should not be modified in any way. Parts for 1984 and earlier engines are still available.