TSB210204-051420

6/1/2021
External Lubricating Oil Leak from Crankcase Breather Tube
Technical Service Bulletin
Technical Service Bulletin: TSB210104
Released Date: 14-May-2021
External Lubricating Oil Leak from Crankcase Breather Tube
External Lubricating Oil Leak from Crankcase Breather Tube
Warranty Statement
The information in this document has no effect on present warranty coverage or repair practices, nor does it authorize TRP or
Campaign actions.
Contents
Product Affected
L9 CM2450 L126B
Issue
Equipment with fewer than 5,000 miles experiencing external lubricating oil leak from crankcase breather tube.
Symptom:
Significant lubricating oil carryover from crankcase breather tube, pooling or dripping oil on starter, wiring harnesses, and/or
vehicle components including frame, lubricating oil pan, or body. See Figure 1 below.
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External Lubricating Oil Leak from Crankcase Breather Tube
Figure 1, Left: Signs of Excessive Oil from Crankcase Breather Tube. Right: Normal Oil from Crankcase Breather Tube.
Root Cause:
Debris from valve cover manufacturing process can plug the lubricating oil separator breather system, preventing lubricating oil
from draining back to the crankcase.
Verification
Verify equipment has fewer than 5,000 miles.
Following published troubleshooting leads to finding external lubricating oil leaking from crankcase breather tube.
Resolution
Remove oil separator breather. See L9 CM2450 L126B Service Manual, Bulletin 5613077. Refer to Procedure 003-002 in
Section 3. (/qs3/pubsys2/xml/en/procedures/583/583-003-002.html)
Clean valve cover of all debris using solvent and a lint free rag.
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External Lubricating Oil Leak from Crankcase Breather Tube
Replace oil separator breather with new. See L9 CM2450 L126B Service Manual, Bulletin 5613077. Refer to Procedure 003-002
in Section 3. (/qs3/pubsys2/xml/en/procedures/583/583-003-002.html)
Document History
Date
2021-5-13
Details
Module Created
Last Modified: 14-May-2021
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