BULLETIN NOTES
APPLICABLE MODEL(S)/VINS
2018-2023 CX-5 2.5L with cylinder deactivation
2020-2023 CX-30 2.5L with cylinder deactivation
2019-2023 Mazda3 (Japan built) 2.5L with cylinder deactivation
2019-2023 Mazda3 (Mexico built) 2.5L with cylinder deactivation
2018-2021 Mazda6 2.5L with cylinder deactivation with VINs lower than JM1 GL**** ** 620105 (Produced before Nov.
12, 2021)
NOTE: This service information applies to vehicles with SKYACTIV-G 2.5 (PYUD engine) with cylinder deactivation.

DESCRIPTION
Some vehicles may exhibit oil seepage or oil leak onto the engine front cover, which becomes more apparent with dust
adhesion.

Customers experiencing this concern should have their vehicle repaired using the following repair procedure.
REPAIR PROCEDURE
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1. Verify the customer concern.
Situation1:
When you receive a customer complaint for this concern, confirm the oil seepage or leak and repair it according to the
procedure below.
Situation2:
When you find an oil leak or seepage during vehicle inspection, refer to "Repair Standards for Resealing" below, and
repair it according to the procedure below.
Repair Standards for Resealing
Front cover
Oil is dripping.
The area around the cover is heavily soiled with oil
and dust.
Oil adheres to the oil seepage area by touching it.

Under cover
Oil accumulation on cover.
Oil adheres to the oil leakage marks by
touching it.

Need to
repair

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No need to
repair

The oil is completely dry by touching the oil seepage
area.

No oil accumulation on cover.

Procedure for Oil Seepage or Leak
Correctly follow the cleaning process and appropriate amount of sealant to eliminate any future requirement to reseal.
This prevents a second repair 1-3 years later, which would not be covered under warranty.
1. Remove the engine front cover according to the MGSS online instructions TIMING CHAIN REMOVAL/INSTALLATION
[SKYACTIV-G 2.5 (WITH CYLINDER DEACTIVATION)]).
CAUTION: When removing the front cover, be sure to remove the oil pan at the same time. Insufficient cleaning
of the mating face of the oil pan may cause oil leakage.
2. Completely clean and remove oil, dirt, sealant or other foreign matter that may be adhering to the engine front cover,
cylinder head, or engine block.
CAUTION: If oil, dirt and sealant remains on the sealant application area, the silicone sealant will not seal
properly, which will cause oil leakage.
3. When reusing the engine front cover installation bolts, remove sealant from the bolts.
CAUTION: If a bolt with sealant (1) on it is used, it could result in cracks (2) in the cylinder head and engine block.

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4. Install new O-rings to the engine front cover.
CAUTION:
• Install the O-rings so that the tabs of the O-rings recede into the notches.
• Do not use any sealant on the O-rings.

5. Apply silicone sealant (TB1217D or equivalent) to the engine front cover, as shown below.
CAUTION: Apply the silicone sealant to the area (A) between the cylinder block (B) and head (C) so that it goes into the
cylinder head gasket (D).

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CAUTION:
• Apply the silicon sealant in a single, unbroken line.
• To prevent silicone sealant from hardening, adhere the engine front cover and engine block firmly within 10 minutes
after applying silicone sealant. After adhering them, tighten the installation bolts immediately.
• Mazda Sealant has an expiration date, check the tube to be sure it has not been opened and it has not expired.

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Bead thickness
A: 2—6 mm {0.1—0.2 in}
B: 4—6 mm {0.16—0.23 in}
C: 4—8 mm {0.2—0.3 in}
Reference information: Sealing Mechanism
Sealant (2) spreads to the step bead (1) and sealing performance is ensured.
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Before assembly
1

Step bead

2

Sealant (TB1217D or equivalent)

3

Front cover

4

Engine

Assembled

The following are required to achieve the effective sealing.
1 Clean and degrease the mating surfaces.
2 Apply the proper amount and location of sealant.
The ground contact area between the sealant and the cover is small and does not provide sufficient sealing.

Dust gets into the mating
surfaces

The place of application is
out of alignment

Too little sealant

Overlapping sealant may adversely affect internal engine parts.

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Too much sealant

Notes on resealing the front cover:
The following areas (1) have a smaller step bead (2), so be careful about the amount and location of sealant application.

6. Install the front seal with SST and engine front cover according to the MGSS online instructions TIMING CHAIN
REMOVAL/INSTALLATION [SKYACTIV-G 2.5 (WITH CYLINDER DEACTIVATION)]).
Engine Front Cover Installation Note:
NOTE: For a new engine front cover, the positioning pins in the two locations shown below project to the outside of the
engine.

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NOTE: If the engine front cover is newly replaced, tap the positioning pins in the two (2) locations to the seal surface
side.

NOTE: Temporarily install a M8 × 1.25 bolt (length 40 mm {1.6 in} to the drive belt auto tensioner installation bolt hole (1)
to prevent the following:
• A silicone sealant adhesion malfunction in the drive belt auto tensioner installation bolt hole.
• A bolt mis-installation due to silicone sealant hardening.

7. Tighten the engine front cover installation bolts in the order shown below.
CAUTION: For the number 10 bolt of the tightening order, install the bolt with a new washer.
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Tightening torque
20—26 N·m {2.1—2.6 kgf·m, 15—19 ft·lbf}
8. Remove the bolt installed to the drive belt auto tensioner installation bolt hole when installing the drive belt auto
tensioner.
9. Re-install the other removed parts.
10. Verify the repair.

PARTS INFORMATION
Parts Number

Description

Qty.

Notes

PYFA-10-235

GASKET, HEAD COVER

1

[R]

PE01-12-257

RING,'O'

1

[R] for electric variable valve timing motor/driver

ZJ01-10-243

WASHER, SEALING

1

[R] for front cover

PE01-10-602

SEAL, OIL

1

[R] for front oil seal

PYFA-10-673

RING,'O'

3

[R] for front cover

9956-41-400

GASKET

1

[R] for oil pan drain plug

0000-77-1217-ES

SILICONE

1

---

[R]: Replacement parts
Replacement parts location
• Gasket for cylinder head cover

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• O-ring for electric variable valve timing motor/driver
• Other parts for front cover
• Gasket for oil pan drain plug

WARRANTY INFORMATION
NOTE:
• This warranty information applies only to verified customer complaints on vehicles eligible for warranty repair.
• This repair will be covered under Mazda’s New Vehicle Powertrain Warranty term.
• Additional diagnostic time cannot be claimed for this repair.
Warranty Type

A

Symptom Code

76

Damage Code

99

Part Number Main Cause

7777-SP-X26

Quantity
Operation Number / Labor Hours:

0
XXWBKXAX / 3.6 Hrs. (CX-5 / Mazda6)
XXWBKXAX / 3.8 Hrs. (CX-30 / Mazda3)

NOTE: Claim the engine oil (Max. 4.3 L {4.5 US qt, 3.8 lmp qt}) as related parts.

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