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Replacing a Radiator on a 1999 - 2004 Honda Odyssey (With Video)

Hardlymoving writes about do-it-yourself automobile maintenance on various makes and models.

Radiator for the Honda Odyssey (Denso Brand)

Radiator for the Honda Odyssey (Denso Brand)

Replacing the Honda Odyssey Radiator

This article shows you the steps involved in replacing a Honda Odyssey radiator. Because the transmission oil passages have a tendency to clog up and cause transmission shifting problems, replacing the radiator may resolve transmission shifting issues. I replaced this radiator after installing a rebuilt transmission.

Denso is the OEM (Original Equipment Manufacturer) for the Honda radiator.

It is not necessary to remove the front bumper fascia or the A/C condenser. This is a moderately complex job, but it requires only basic tools. In addition to the radiator, you will need at least a gallon of replacement coolant, unless you save the old coolant. You should also have a quart of Honda Honda ZF ATF on hand because there will be some ATF loss from the radiator replacement.

Video of 1999 - 2004 Honda Odyssey Radiator Replacement (Audio Not Present)

This 9-minute video will provide you with step-by-step help for completing the replacement of a Honda Odyssey radiator. The steps are also described lower down in the article.

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Step-by-Step Instructions: Honda Odyssey Radiator Replacement

1. Remove the Upper and Center Radiator Plastic Covers

1. Remove the push pins that hold the upper plastic radiator cover. To get the center pin up, use either a screwdriver or push-pin pliers.

2. Remove the three (3) push pins that hold the plastic front radiator cover. Slightly bend the cover forward to gain access to the push pins.

2. Remove the Upper Radiator and A/C Condenser Brackets and the Hood Latch

  1. Remove the two brackets that hold the upper portion of the radiator.
  2. Remove the two brackets that hold the upper portion of the A/C condenser.
  3. Remove the two bolts that hold the hood latch. Pull out the latch and move it away from the radiator.

3. Drain the Coolant, Remove the Upper Fan Shroud Bolts, and Disconnect the Reservoir Hose and Upper Radiator Hose

  1. Place a large splash pan (like a plastic concrete mixing container you can buy at Home Depot) under the lower radiator hose. Loosen the lower radiator hose clamp and pull the hose off the radiator. Let the coolant spill into the pan. You can also screw off the drain plug to drain the coolant, but it takes a while to drain out.
  2. Remove the two (2) nuts for each of the fan shrouds: driver's side for the radiator fan, passenger side for the A/C condenser fan.
  3. Disconnect the coolant reservoir hose from the radiator and pull the hose away from the radiator.
  4. Loosen the hose clamp on the top radiator hose connected to the radiator and pull the hose away from the radiator.

4. Disconnect the Lower Transmission Lines and Lower A/C Condenser Fan Shroud Bolts

  1. To gain better access to the lower transmission lines, elevate the front passenger wheel off the ground with a hydraulic jack and support the vehicle with a jack stand.
  2. Disconnect the two (2) radiator-side transmission ATF lines.
  3. Remove the two (2) 10-mm bolts that hold the lower portion of the A/C condenser shroud. The bolts are hard to see, but can be reached by feel using a 10-mm-long socket.

5. Remove the Radiator Fan Shroud and the Center Support Bracket

  1. Disconnect the fan motor electrical connection and remove the radiator fan shroud. Lift and tilt the bottom end of the shroud past the bottom radiator and ATF hose connectors, then lift the shroud out of the car.
  2. Between the radiator and A/C condenser fan shrouds is a vertical support bracket held in place by one bolt on the bottom and two bolts on the top. Remove the bolts and then the bracket.

6. Remove the Old Radiator

  1. Tilt the top of the radiator forward and lift the radiator out. You can leave the A/C condenser fan in the car.

7. Install the New Radiator

  1. To ease installation of the new radiator, temporarily remove the ATF hose connector and the top condenser bracket.
  2. Ensure that the bottom rubber radiator mounts are seated in the bottom mounting holes.
  3. Tilt the radiator back into the car.

8. Bolt on the A/C Condenser Shroud and Center Support Bracket, and Connect ATF Lines, Hoses, and Electrical Fittings

  1. Bolt on the two 10-mm bolts to the bottom of the A/C condenser shroud.
  2. Reconnect the brass ATF connectors to the radiator.
  3. Attach the ATF hoses to the ATF connectors and secure the hose clamps.
  4. Install the center support bracket that fits between the radiator and A/C condenser fan shrouds.
  5. Re-connect electrical fittings.
  6. Install the A/C condenser top bracket.

9. Install the Radiator Fan Shroud

  1. Position the radiator fan shroud bottom contact fittings into the car chassis's rubber bushings.
  2. Install the top two (2) radiator fan shroud mounting bolts.
  3. Connect the fan motor's electric connector.

10. Install the Hood Latch Assembly and Connect the Top Radiator Hose

  1. Install the two (2) bolts that attach the hood latch assembly to the upper cross frame.
  2. Attach the radiator hose to the top radiator hose connector and fasten the radiator hose clamp.

11. Install the Top Radiator Brackets and the A/C Condenser Brackets

  1. Install the two (2) top radiator brackets.
  2. Install the six (6) top A/C condenser brackets.

12. Connect the Coolant Reservoir Line to the Radiator

  1. Feed the coolant reservoir line through the cross frame and attach the line to the radiator. Secure the line with either a hose clamp or a zip tie.

13. Attach the Lower Radiator Hose

  1. Attach the lower radiator hose to the bottom of the radiator and secure with a hose clamp.

14. Install the Upper and Center Radiator Plastic Covers

  1. Position and install the front plastic radiator cover and install the three (3) push pins that hold it in place.
  2. Position and install the upper plastic radiator cover. Secure the cover with the push pins.

15. Add Coolant to the Radiator

  1. Add coolant to the radiator.
  2. With the radiator cap off, start and run the car. As the coolant fills in the air gaps in the cooling system, add more coolant.

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

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