25-2428

TECHNICAL SERVICE BULLETIN
Loss Of Engine Coolant

09 September
2025

This bulletin supersedes 25-2063. Reason for update: update the Service Procedure.
Model:
Ford
2021-2024 Bronco Sport

Engine: 1.5L EcoBoost

Markets: North American markets only
Issue: Some of the vehicles listed in the Model statement above may exhibit a loss of engine coolant from a leak at
the coolant pump. This may be due to contamination in the engine's cooling system.
Action: For vehicles that meet all of the criteria in the Issue and Model statements, follow the Service Procedure to
flush the engine cooling system and replace the coolant pump.
NOTE: The water pump pulley bolts are reused in this repair if there is no damage to the bolts identified. This
may differ from current WSM direction.
Parts
Service
Part
Number

Claim
Quantity

Package
Order
Quantity
1 Kit

Number in
Package

Description

Note

Air Conditioning O-Ring

Kit contains 2 each of
1/2 inch, 5/8 inch, 8
mm (6 total pieces)

DS7Z19B596-A

1 Kit

1 Kit

DL3Z19B596-B

1

1

1

HX7Z-8501B

1

1

1

VC-13DL-G

As
Needed

As Needed

Motorcraft® Yellow Prediluted
Antifreeze/Coolant (All Markets
Except Canada)

CVC-13DLG

As
Needed

As Needed

Motorcraft® Yellow Prediluted
Antifreeze/Coolant (Canada Only)

VC-1

As
Needed

As Needed

Motorcraft® Premium Cooling
System Flush

YN-35

As
Needed

As Needed

Motorcraft® R-1234yf Refrigerant
PAG Oil

YN-12-D

As
Needed

As Needed

Motorcraft® PAG Refrigerant
Compressor Oil

YN-33-A

As
Needed

As Needed

R-1234yf Refrigerant (All Markets
Except Canada)

HS7Z19B519-BA

As
Needed

As Needed

R-1234yf Refrigerant (Canada
Only)

YN-19

As
Needed

As Needed

Motorcraft® R-134a Refrigerant
(All Markets Except Canada and
Mexico)

CYN-19-RB

As
Needed

As Needed

Air Conditioning O-Ring / Gasket
Kit (Compressor Inlet Line)
Coolant Pump

R-134a Refrigerant (Canada Only)

R-134a

MYN-19

As
Needed

As Needed

Motorcraft® R-134a Refrigerant
(Mexico Only)

Service part numbers and "number in package" quantity may change after publication, thus also affecting the
"package order quantity". Refer to the parts catalog for the latest information.
Claim Quantity refers to the total number of individual pieces required to repair the vehicle.
Package Order Quantity refers to the amount of the service part number package(s) required to repair the vehicle.
Number In Package refers to the number of individual pieces included in a service part number package.
As Needed indicates the part is necessary but amount of the part may vary and/or is not a whole number. Parts can
be billed out as non-whole numbers, including less than 1.
Warranty Status: Eligible under provisions of New Vehicle Limited Warranty (NVLW)/Service Part Warranty
(SPW)/Service Part New Vehicle (SPNV)/Extended Service Plan (ESP) coverage. Limits/policies/prior approvals are
not altered by a TSB. NVLW/SPW/SPNV/ESP coverage limits are determined by the identified causal part and
verified using the OASIS part coverage tool.
Labor Times
Operation
No.

Description
2021-2024 Bronco Sport 1.5L EcoBoost: Pressure Test Engine Cooling System To Verify Leak
(Fail) Flush Engine Cooling System And Replace The Coolant Pump Following The Service
Procedure (Do Not Use With Any Other Labor Operations)

252428A

Time
3.1
Hrs.

Repair/Claim Coding
Causal Part:

8501

Condition Code: D8

Service Procedure
1. Perform a Cooling System Pressure Test. Refer to the WSM, Section 303-03A Engine Cooling - 1.5L EcoBoost >
Diagnosis and Testing. Is the coolant pump leaking?
(1). Yes - proceed to Step 2.
(2). No - this article does not apply. Continue with normal WSM diagnosis.
2. Add Motorcraft® Premium Cooling System Flush to the cooling system and top off with water as needed and allow
the engine to idle for 30 minutes.
3. Drain the cooling system and leave the radiator drain valve open. Refer to the WSM, Section 303-03A Engine
Cooling - 1.5L EcoBoost > Engine Cooling System Draining, Vacuum Filling and Bleeding.
4. Remove the air cleaner. Refer to WSM, Section 303-12A Intake Air Distribution and Filtering - 1.5L EcoBoost >
Removal and Installation > Air Cleaner.
5. Loosen the clamp and remove the air cleaner outlet pipe in Figure 1.
Figure 1

6. Release the clamps and disconnect the upper and lower radiator hoses from the radiator.
7. Flush the radiator for 2-3 minutes by inserting/connecting a freshwater hose or flush machine in the upper hose
port of the radiator.
8. Using compressed air regulated down to 20-30 psi, blow compressed air through the upper hose connection of the
radiator for 1-2 minutes to remove any remaining water.
9. Remove the coolant pump. Refer to WSM, Section 303-03A Engine Cooling - 1.5L EcoBoost > Removal and
Installation > Coolant Pump.
(1). The water pump pulley bolts can be reused for this repair if there is no damage to the bolts identified. This
may differ from current WSM direction.
10. Release the clamp and disconnect the heater core return hose from the hose connection near location shown in
Figure 2.
Figure 2

11. Using a hose clamping tool, clamp off the coolant bypass hose in the location shown just below the intake
manifold and throttle body, near the fan motor in Figure 3.
Figure 3

12. Using a hose clamping tool, clamp off the upper radiator hose. (Figure 4)
Figure 4

13. Flush the heater core and engine for 2-3 minutes by connecting a freshwater hose or flush machine to the heater
core return hose as shown above in Figure 4.
14. Using compressed air regulated down to 20-30 psi, blow compressed air through the heater core return line for 12 minutes to remove any remaining water.
15. Remove all the hose clamping tools. Connect the upper and lower radiator hoses and close the radiator drain
valve.
16. Install the new coolant pump. Refer to WSM, Section 303-03A Engine Cooling - 1.5L EcoBoost > Removal and
Installation > Coolant Pump.
(1). The water pump pulley bolts can be reused for this repair if there is no damage to the bolts identified. This
may differ from current WSM direction.
17. Connect the heater core return hose.
18. Install the air cleaner outlet pipe and tighten the clamp to 42 lb-in (4.8 Nm).
19. Install the air cleaner. Refer to WSM, Section 303-12A Intake Air Distribution and Filtering - 1.5L EcoBoost >
Removal and Installation > Air Cleaner.
20. Fill cooling system. Refer to the WSM, Section 303-03A Engine Cooling - 1.5L EcoBoost > Engine Cooling
System Draining, Vacuum Filling and Bleeding. Repeat Steps 10-14 a total of 10 times to remove any remaining air
trapped in the system.
(1). Repeating Steps 10-14 differs from current WSM direction, but performing this process 10 times is required
for this particular repair.

© 2025 Ford Motor Company
All rights reserved.
NOTE: The information in Technical Service Bulletins is intended for use by trained, professional technicians with the knowledge, tools, and
equipment to do the job properly and safely. It informs these technicians of conditions that may occur on some vehicles, or provides information
that could assist in proper vehicle service. The procedures should not be performed by "do-it-yourselfers". Do not assume that a condition
described affects your car or truck. Contact a Ford or Lincoln dealership to determine whether the Bulletin applies to your vehicle. Warranty Policy
and Extended Service Plan documentation determine Warranty and/or Extended Service Plan coverage unless stated otherwise in the TSB article.
The information in this Technical Service Bulletin (TSB) was current at the time of printing. Ford Motor Company reserves the right to supersede
this information with updates. The most recent information is available through Ford Motor Company's on-line technical resources.