Tech Tip: Mazda Leak From Rear Heater Pipe – UnderhoodService

Tech Tip: Mazda Leak From Rear Heater Pipe

During winter driving, especially in the 23 "Salt Belt" states, water containing salt may accumulate in the black plastic pipe cover and/or the brackets of the wheel housing. This may cause corrosion and perforation of the rear heater pipe, resulting in coolant seepage from the rear heater pipe.

During winter driving, especially in the 23 “Salt Belt” states, water containing salt may accumulate in the black plastic pipe cover and/or the brackets of the wheel housing. This may cause corrosion and perforation of the rear heater pipe, resulting in coolant seepage from the rear heater pipe. To correct this concern, mass production has been changed as follows:

1. The material of the heater pipe has been changed from steel to aluminum.

2. A urethane protector has been added around the rear heater pipe, and the black plastic pipe cover for the wheel housing has been deleted.

Vehicles with this concern should be repaired using the procedure shown in this bulletin.

Applicable Model(s)/VINs:

2000-’01 MPV (equipped with rear heater) with VINs JM3 LW28**Y0100038 – 10214436 (built March 31, 1999 through Aug. 8, 2003)

2002-’03 MPV (equipped with rear heater) with VINs JM3 LW28**20300025 – 30378937 (built March 31, 1999 through Aug. 8, 2003)

Repair Procedure:

1. Secure the vehicle on a hoist.

2. Raise the vehicle and locate the rear heater pipe (rear) in the right rear wheel well.

3. Remove the black plastic pipe cover. Note: Discard the black plastic pipe cover. It will not be reused.

4. Inspect the rear heater pipe (front) and rear heater pipe (rear) for signs of coolant seepage.

Note: The rear-side bracket is more likely to be rusted. If there is no rust or rust is very light (white rust), replacement is not required.

5. Remove the seeping side of the rear heater pipe.

Note: It is not necessary to remove the front crossmember and stabilizer bar to remove the rear heater pipe (front).

6. If the rear-side of the rear heater pipe is seeping and needs to be replaced, also inspect the heater pipe attachment bracket for rust, corrosion or breakage after the rear heater pipe (rear) is removed.

7. Using a power cutting tool, cut off the top of the bracket leaving only welded bracket flanges. See Fig. 1.fig. 1

Warning: Be sure to wear safety goggles when using power cutting/grinding tools.

Caution: After cutting the top of the bracket off, grind any sharp edges off the flanges.

8. Place the new bracket on top of the welded flanges. See Fig. 2.fig. 2

9. Mark the holes using the new bracket as a template.

10. Using a 4 mm drill bit, drill two holes.

11. Apply rust-preventative sealer inside the new holes.

12. Attach the new bracket to the body using two self-tapping screws.

13. Once the bracket is secured, apply silicon-based sealer on top of the screws and flanges. See Fig. 3.fig. 3

14. Install the new rear heater pipe (rear), securing it to the bracket.

15. If the rear heater pipe (front) is also seeping and needs to be replaced, install a new one. Note: It is not necessary to remove the front crossmember and stabilizer bar to install the rear heater pipe (front).

16. Add coolant to the cooling system. See Fig. 4. Fig. 4

Note: If the vehicle is equipped with a water valve (under hood), ensure the valve is in the “open” position. If the valve is closed, the front heater will not provide heat. Refer to service bulletin 07-004/04 (MPV – Lack of Warm Air From Front Heater) issued Aug. 02, 2004 for additional information.

17. Verify proper heater operation once the repair is complete.

18. Complete an “Authorized Modification Label” with “SSP65” written on the sticker and affix it to the vehicle’s hood.

Courtesy of ALLDATA.

 

You May Also Like

HVAC Sensors: More Than Just Temperature

When a driver sets a temperature in the control head of an HVAC system, what does it mean to the vehicle? Seventy-two degrees could mean many different settings depending on the outside temperature, humidity and even the position of the sun.

When a driver sets a temperature in the control head of an HVAC system, what does it mean to the vehicle? Seventy-two degrees could mean many different settings depending on the outside temperature, humidity and even the position of the sun.

When a passenger decides that 70 degrees is a better temperature for their zone, things get even more complicated. Automatic Temperature Control (ATC) systems require a complex array of internal and external sensors that include ambient air temperature sensors, interior temperature sensors, outlet duct and evaporator temperature sensors, pressure sensors, humidity sensors, blend door position sensors and sunload sensors.

Nearly 5,000 To Participate In Auto Value, Bumper To Bumper ‘Festive Walk’ To AAPEX 2018

On Thursday, Nov. 1, nearly 5,000 Auto Value and Bumper to Bumper automotive professionals wearing matching yellow shirts will begin their “festive walk” from the Mirage hotel to AAPEX 2018 at the Sands Expo, temporarily shutting down the busy Las Vegas Boulevard along the way.

Drive Belt Checklist: What Are You Missing?

You might have only one chance to sell a customer a new serpentine belt. With belts lasting roughly 90,000 miles, proper inspection at the time of failure is critical not only for selling the belt, but also for ensuring add-on sales and better customer satisfaction.

VIDEO: Using Airflow To Sell Cabin Air Filters

Andrew Markel introduces an inexpensive tool that can assist in selling cabin air filter replacements. Sponsored by Auto Value and Bumper to Bumper.

airflow-selling-cabin-air-filter-video-featured
Air Conditioning Odor Causes

Air conditioning odors typically result from the uncontrolled growth of bacteria and other microorganisms in the evaporator. Research by independent laboratories has found fungi such as Aspergillus, Cladesporium, Penicillium and others growing on cooling coils and other A/C system areas.

ac air conditioning smells featured

Other Posts

HVAC Diagnostics

Knowing the cause of the complaint might require looking at several components.

Solving Intermittent Overheating

New cooling systems anticipate and influence changes in coolant temperature.

Climate Control Modules

HVAC control modules may fail when the contacts and switches become inoperable. Sponsored by The Group Training Academy.

Solving No Heat Complaints

Here are 10 guidelines for making sure a customers heat functions.