Service Bulletin
SB891-3
Date:

August 15, 2025

Subject:

Engine Oil Leak Identification Between Block and Gearcase – Yanmar Common
Rail Engines

Location:

e-Tech Library

Units:

Thermo King Diesel Powered Units with Yanmar Common Rail Engines:
TK488CR, TK488CR1, TK488CRH1, TK488CRE1 engines found in Precedent S600, S-610M, S-610DE, S-700, S-750i, SGUM 5000 and SGCO 5000 units with
engine build dates August 2021 through May 2023 only. Engine build dates
can be found on the emission label, see page 4 of this bulletin for location and
identification.

Description:

Thermo King has identified two causes for an oil leak behind the injection pump
on common rail engines. These leaks are found behind the injection pump, in
between the engine block and gearcase. See pages 4, 5, and 6 of this bulletin for
images and pictures detailing the leak area.
1 - In 2022, the root cause of the oil leak was identified as a deformed O-ring
behind the gear case cover.
2 - In 2023, the root cause of the oil leak has been identified as either thin,
missing, or uncured sealant between the engine block and gear case.
NEW: A Yanmar approved epoxy leak repair is now available. See Repair B:
Epoxy Procedure (Section 8) of manual TK 57337 detailing this new procedure.
NEW: Inspect and determine the oil leak rate A or B. See page 4 of this bulletin
for leak rate inspection details.
Oil Leak Location:

1

If an oil leak is found in this area:
1. Take pictures of the current oil leak area BEFORE any clean-up.
2. Clean the engine gearcase leak area to pinpoint oil leak location. If
needed, commercially available oil leak detection powder may be used to
help pinpoint the leak area.
3. Run the engine for 30 minutes (or until the leak can be identified).
4. Verify oil leak source is located behind the engine block and gearcase as
shown on page 1, 4, 5, and 6 and take pictures.
5. Determine the oil leak rate (A or B) as shown on page 4 of this bulletin.

Oil Leak Rate A = Gearcase Cover Replacement Repair A:
Prior Authorization Required from Thermo King Service Dept.
A. Fill out the form on page 7 of this bulletin.
B. Take pictures of the oil leak BEFORE any clean-up (examples on page
4) and the emission label (example on page 4).
C. Submit completed form, oil leak pictures, and emissions label pictures
to: Salesforce Ticket Form for authorization.
D. After authorization is granted, order the correct gearcase cover kit (see
page 3) from the dealer portal and use the authorization number to
complete the order.
E. Follow gearcase replacement procedures (Repair A) as detailed in
manual TK 57337.
F. Submit a warranty claim in TAVANT including pictures of the oil leak
and the emission label. Also attach the completed form from page 7 and
the authorization number.

Oil Leak Rate B = Epoxy Repair B:
Prior Authorization NOT Required
A. Fill out the form on page 7 of this bulletin.
B. Take pictures of the oil leak BEFORE any clean-up (examples on page
4) and the emission label (example on page 4).
C. Order epoxy repair kits shown on page 3.
D. Follow epoxy procedure (Repair B) as detailed in manual TK 57337.
E. Submit a warranty claim in TAVANT including pictures of the oil leak
and the emission label. Also attach the completed form from page 7.
IMPORTANT: See WB530 for TAVANT claim submission details.
Labor Time:

Unit / Repair
Gearcase Cover Replacement Repair A
(Non SmartPower Units)
Gearcase Cover Replacement Repair A
(SmartPower Equipped Units)
Epoxy Repair B
(All Units)

2

Time
18.5 Hours
21.5 Hours
4.0 Hours

Parts:

Unit / Repair
Silver Gearcase Cover Kit for Repair A
(S-600, S-610M, and S-610DE Units)
Tan Gearcase Cover Kit for Repair A
(S-700 Units)
Epoxy Kits for Repair B
(All Units)

Kit Part Numbers
018131
018134
018139 (epoxy and parts kit)
018140 (reusable epoxy applicator)

Note: SG5000 units can use either kit; the timing cover color will not match.
IMPORTANT: Gearcase replacement kits 018131 and 018134 for repair A are
not orderable until after authorization is granted. The form on page 7 must be
filled out and sent in with pictures for prior authorization and parts shipment.

Procedure:

Instructions for repairs A and B are located in e-Tech Library:
TK 57337 - TK488CR and CR1 Series Engine Gear Case Service Manual
Repair A: Gearcase Cover Reseal / Replacement (Sections 2–7 in TK 57337)
Repair B: Epoxy Procedure (Section 8 in TK 57337)
IMPORTANT (Repair A): DO NOT remove the camshaft gear from the camshaft.
The rear main seal MUST BE REPLACED. If the seal is not replaced, the
warranty claim will be denied (if applicable).
IMPORTANT (Repair B): DO NOT START OR RUN THE ENGINE UNTIL THE
EPOXY HAS CURED.
Epoxy curing is affected by ambient and engine block temperatures. Follow the
guidelines below based on the average ambient and engine block temperatures.
A warmer and longer cure time will improve adhesion and sealing performance.
It is recommended that the epoxy is only applied to an engine block with
temperatures above 50ºF (10ºC). Measure the block temperature using a
commercially available infrared thermometer. If heating is required, use a
commercially available electric heater or heat gun. DO NOT exceed a heating
temperature of 300ºF (148ºC) - damage to the epoxy will occur.
Average Ambient and Engine Block
Temperature During Epoxy Cure Time

Epoxy Cure Process
Epoxy must cure for at least 16 hours (no heating
required).

65ºF (18.3ºC) or Higher

Between 50ºF (10ºC) and 64ºF (17.7ºC)

Heat the epoxy and engine block area (after the
epoxy is applied) to approximately 140ºF (60ºC) for
30 minutes, then remove the heat source. Let
epoxy cure for at least 16 hours at any ambient
temperature. The unit can be outside during the
cure process, down to -50ºF (-45ºC).
NOTE: To avoid damage to the epoxy, DO NOT
exceed a heating temperature of 300ºF (148ºC).

3

Determine Oil Leak Rate A or B:
Leak Rate A
Repair A

Leak Rate A:
Has accumulating oil on the sump,
generator, and belly pan of unit.
Commonly seen as an unacceptable
leak rate that needs to be addressed
immediately.

Leak Rate B
Repair B

Leak Rate B:
Has staining on the block
with wetness and some
dripping onto oil pan.
Commonly seen as an
unacceptable leak rate.

Leak Rate B:
Has staining on the block
visible from the low-pressure
leak (crankcase pressure)
and some wetness. May
require leak detection powder
to find leak source.
Commonly seen as an
acceptable leak rate.

Engine Emission Label Location Showing Engine Build Date (YYYY/M):

4

Oil Leak Location

Cause of Leak: Deformed O-Ring

Cause of Leak:
Thin, Missing, or Uncured Sealant Between Engine Block/Gear Case

5

Oil Leak Detail View

6

Yanmar Common Rail Engine Oil Leak Kit Approval Form
(All Form Fields Must Be Complete for Approval)

Yanmar Common Rail Engine Oil Leak Kit Approval Information
Today’s Date
Unit Date in Service
Dealer Name and Location
Dealer Number
Contact Information (phone # / email)
Customer / Fleet / Location
Unit Model
Unit Serial Number
Engine Serial Number
Engine Model Year (YYYY/M)
Engine Hours (not unit hours)
Inspect/Determine Oil Leak Rate A or B?

***For Gearcase Replacement Repair A Only***
Please remember to attach oil leak and emission label pictures in Salesforce
Link: Salesforce Ticket Form

Or on the Dealer Portal page Select Dealer Support

Then Select My Cases (Salesforce)

7

Additional Epoxy Warranty Information (Repair B):
The warranty period for the epoxy repair is 84 months (7 years) after the repair date.
Thermo King will accept warranty coverage for up to two applications of the epoxy repair
when the following conditions are met:
- The first epoxy application repair must have been placed into service with the customer.
- The leak rate (A or B) must meet the epoxy repair requirements found on page 2 of this
bulletin.
If the epoxy repair fails within the above warranty period, gearcase replacement (Repair A) is
deemed to be the final remedy to the oil leak unless Thermo King Technical Service deems
otherwise.
After epoxy application (Repair B) or gearcase replacement (Repair A), Thermo King is not
liable for engine oil leaks due to poor workmanship within the first 3000 hours or 12 months,
whichever occurs first.
This warranty only applies to engines within the build date range as stated on page 1 of this
bulletin.

8