Usage:
3406B Industrial, Marine, Vehicular, Generator Set And Truck Engines
- SUPPLEMENT: 06/03/85
SERVICE MAGAZINE, OCTOBER 29, 1984, PAGE 6. The article "New Cylinder Heads, Fuel Nozzles And Fuel Nozzle Adapters Used" is not complete. Add the information that follows to the end of the article.
Put 5P3931 Anti-Seize Compound on the threads of the 7W1645 Fuel Nozzle Adapter before installation in the cylinder head. Use an 8T3201 Wrench to tighten the adapter to a torque of 205 ± 14 N·m (150 ± 10 lb ft).
Use an 8T3139 Spanner Wrench to tighten the 7W2315 Retainer to a torque of 48 ± 7 N·m (35 ± 5 lb ft).
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Reference: Service Magazine, October 15, 1984, Page 2, New High Alloy Material Is Used In Cylinder Head Assemblies.
Description of Change: Changes have been made to provide a stronger cylinder head on 3406B Engines. The new cylinder head is made from a high alloy material. See the reference article. The fuel nozzle bore in the new cylinder head is 40.45 mm (1.593") diameter. The former cylinder head has a fuel nozzle bore of 55.12 mm (2.170") diameter. These changes will provide a much stronger cylinder head and reduce the possibility of cylinder head cracking.
A new fuel nozzle adapter is used to fit the smaller bore in the new cylinder head. The new adapter holds the nozzle in place with a retainer that threads into the top of the adapter. See the illustration. This method of clamping the nozzle eliminates the need for the former clamping bolt.
The new fuel nozzle is identical to the former fuel nozzle except for a larger recessed hex on the top of the nozzle. The recessed hex allows the retainer to fit over the nozzle and seat correctly. The former nozzles cannot be used with the new adapters.
A new washer (gas seal) is used between the fuel nozzle and fuel nozzle adapter. The new washer is made of copper instead of nylon. The new washer will not deform during assembly. The new copper washer can be used with the former fuel nozzle and fuel nozzle adapter but the former nylon washer can not be used with the new fuel nozzle and adapter.
Adaptable As: The new cylinder heads, fuel nozzle adapters and fuel nozzles are in effect with the 3406B Engines shown in Chart A and can be adapted to all earlier 3406B Engines. The new parts are shown in Chart B.
Illustration. New adapter with nozzle held in place.
