Usage:
All D330, D333, 3304 and 3306 Engines
- SUPPLEMENT: 12/10/79
SERVICE MAGAZINE, MAY 21, 1979, PAGE 6. The article "Rod Bearings For Parts Service Have Reliefs (Grooves) Cut On The Outside Diameter" did not give clear information. The 7M7821 Bearings (with the relief grooves for bolt clearance) must be used in earlier D330 and D333 Engines that have a 4.50" bore. In later engines that have a 4.75" bore, either the 7M7821 or 4N6258 Bearings can be used. Make a note on your copy of the article to show that these bearings are optional for parts service on later engines.
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The rod bearings used for parts service of the above engines have reliefs (grooves) cut in the outside diameter. See the Illustration. These reliefs give clearance for the rod bolts when these bearings are used on earlier D330 and D333 engines that have a 4.50" bore. The reliefs have no purpose when the bearings are installed on later 4.75" bore engines.
Parts service rod bearing.
On 4.75" bore engines, a 4N6258 Rod Bearing that does not have reliefs is installed at the factory. When it is necessary to install replacement rod bearings, remember the parts service bearings will have the reliefs.
