421-9727 Top End Engine Overhaul Kit for 3412D Marine Engines{1000} Caterpillar

Marine Engine:

3412D MARINE (S/N: REA1-UP)

Introduction

This Special Instruction is intended to provide information on the Engine Overhaul Kit Consist and detailed information on specific parts that should be used based on engine arrangements.

This Engine Overhaul Kit may contain extra parts and extra quantities due to the variety of engine arrangements assigned to a given kit. Refer to the corresponding Parts Manual or Disassembly and Assembly manual in Table 1.

Note: This Kit may contain upgraded parts. These upgraded part numbers may be different than what you have in the parts manual or engine, but these parts have been technically reviewed for compatibility with your application.

Note: This kit contains gasket kits and includes additional parts needed to perform an engine overhaul.

Note: For assistance with technical questions, contact your local Cat dealer.

Note: For more information, visit us at catmarinesupport.com.

Note: For access to our website, you can scan the QR code below with a QR enabled device.

Illustration 1	g03319969

Reference Material

Note: For ordering reference material contact your local Cat dealer.

3412D 421-9727 Top End Overhaul Kit Consist

Note: For assistance or technical questions contact your local Cat dealer.

Note: Refer to Illustration 2 for location of gasket kits.

3412D Engine Gasket Kit Locations

Illustration 2	g03389757
(1) Aftercooler and Lines ( 420-0923 Gasket Kit ) (2) Single Cylinder Head( 420-4502 Gasket Kit ) (3) Fuel System ( 421-1305 Gasket Kit ) (4) Expansion Tank ( 6V-0237 Gasket Kit ) (5) Oil Cooler and Lines ( 421-8976 Gasket Kit )

Gasket Kit Consists

Aftercooler and Lines (420-0923 Gasket Kit)

Refer to Illustration 2.

Single Cylinder Head (420-4502 Gasket Kit)

Refer to Illustration 2.

Fuel System (421-1305 Gasket Kit)

Refer to Illustration 2.

Oil Cooler and Lines (421-8976 Gasket Kit)

Refer to Illustration 2.

Expansion Tank (6V-0237 Gasket Kit)

Refer to Illustration 2.