SB-10044820-4505
Bulletin: M12-11-01
Date: 3/12

SERVICE INFORMATION BULLETIN
Subject: HEATER CORE INLET AND/OR OUTLET TUBE LEAK

Models Affected: ANY MV-1 VEHICLE PRIOR TO VIN 523MF1A69CM100552
EXPERIENCING A LEAKING HEATER CORE INLET AND/OR OUTLET
TUBE CONNECTION

BACKGROUND
Customers may complain of a coolant leak coming from the heater core inlet and/or outlet tube
connection. This condition may be caused by an oversized heater core inlet and/or outlet tube that
prevents the heater hose quick connect(s) from fully engaging.

INSTALLATION TIME
The recommended repair time is 0.9 hour.

WARRANTY
The provisions of the normal warranty policy apply. Labor operation M121101.

PARTS
Heater Hose Quick Connect PN SP001042
One quick connect per oversized or leaking heater core inlet/outlet.

PROCEDURE
WARNING: Always allow the engine to cool before opening the cooling system.
Do not unscrew the coolant pressure relief cap when the engine is operating or
the cooling system is hot. The cooling system is under pressure; steam and hot
liquid can come out forcefully when the cap is loosened slightly. Failure to follow
these instructions may result in serious personal injury.
NOTE: The coolant must be recovered in a suitable, clean container for reuse. If the
coolant is contaminated it must be recycled or disposed of correctly. Failure to follow
these instructions may result in engine or cooling system damage.
NOTE: Vehicle cooling systems are filled with Motorcraft® Premium Gold Engine
Coolant. Always fill the cooling system with the same type of coolant that is present in
the system. Do not mix coolant types. Failure to follow these instructions may result in
engine or cooling system damage.

Copyright© 2012 The Vehicle Production Group LLC

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MV-1 ® is a trademark of The Vehicle Production Group LLC. All rights reserved.
The drawings and diagrams contained herein are for illustrative purposes only, are not to scale, and do not precisely depict the vehicle and parts represented. Drawings and text
may change without notice, and may not reflect the current design.

Bulletin: M12-11-01

Date: 3/12

NOTE: Less than 80% of the coolant capacity can be recovered with the engine in the
vehicle. Dirty, rusty or contaminated coolant requires replacement.

1. Verify that the leaking heater core quick connect isn’t fully seated by pulling on it firmly.
2. Disconnect leaking heater core quick connect.
3. Release the clamp and remove the leaking heater core quick connect from the
hose (See Figure 1).

HEATER
CORE TUBE

QUICK
CONNECT

CLAMP

HOSE

10-WS11-042

Figure 1: Quick Connect Removal/Installation

4. Aquire a Parker 37 Degree Flare Tool (PN 212FB) with a 3/4 inch die from a Parker distributor.
NOTE: Swaging of the heater core inlet and/or outlet tube may take up to three times
before the correct dimensions are achieved. The flaring portion of the Parker Flare
Tool is not used.

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Bulletin: M12-11-01

Date: 3/12

5. Use the Parker Flare Tool with a 3/4 inch die to swage the outer
5-7mm (0.197-0.276 in) of the heater core inlet and/or outlet tube to a diameter of 18.6-19.0
mm (0.732-0.748 in). (See Figures 2 & 3).

5-7 mm

Figure 2: Swaging Dimension

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Bulletin: M12-11-01

Date: 3/12

PARKER
37° FLARE TOOL
(PN 212FB)

10-WS11-040

Figure 3: Swaging with the Parker Flare Tool (PN 212FB)

6.
7.
8.
9.

Install a new heater core quick connect and clamp onto the hose.
Connect the new heater core quick connect to the correct heater core tube.
Verify that the leaking heater core quick connect is fully seated.
Top off the cooling system.
a. Fill the radiator through the radiator fill neck until the coolant level is at the bottom of the
filler neck.
b. The recommended coolant concentration is 50/50 ethylene glycol to distilled water.
- Maximum coolant concentration is 60/40 for cold weather areas.
- Minimum coolant concentration is 40/60 for warm weather areas.
c. Install the radiator cap.
d. Fill the coolant expansion tank until the coolant reaches the COLD FILL mark.
e. On the HVAC control module, move the temperature blend selector to the full WARM
position.

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Bulletin: M12-11-01

Date: 3/12

NOTE: If the air discharge remains cool and the engine coolant temperature gauge
does not move, the engine coolant level is low in the engine and must be filled. Stop
the engine, allow it to cool and fill the cooling system. Failure to follow these
instructions may result in damage to the engine.

f. Run the engine at idle until it reaches normal operating temperature.
g. Add more correct coolant mixture to the coolant expansion tank until the coolant level is at
the COLD FILL mark.
h. Turn the engine off and allow it to cool.
i. Start the engine and allow it to idle until it reaches normal operating temperature. While the
engine is idling, feel for hot air from the A/C vents.
- Hot air should discharge from the A/C vents. The engine coolant temperature gauge
should maintain a stabilized reading in the middle of the NORMAL range and the upper
radiator hose should feel hot to the touch.
j. Check the engine coolant level in the coolant expansion tank and fill it as necessary.
k. Repeat the previous 5 steps as necessary.

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