Parts Catalog Accessories Catalog Tech Info Tech Forums
 
Follow Pelican Parts on Facebook Follow Pelican Parts on Twitter Follow Pelican Parts on Instagram Follow Pelican Parts on YouTube Follow Pelican Parts on Pinterest Follow Pelican Parts on Tumblr
  Search our site:    
View Recent Cars  |   Cart  | Project List | Order Status | Help    
 >  >
Radiator Replacement
 
Bookmark and Share

Pelican Technical Article:

Radiator Replacement

Nick Czerula

Time:

3 hours3 hrs

Tab:

$250

Talent:

****

Tools:

Set of sockets (8mm, 10mm), wrenches (22mm, 30mm), screwdrivers

Applicable Models:

BMW Z3 (1996-02)

Parts Required:

Radiator, hoses, engine coolant, radiator foam seals

Hot Tip:

Work with a cool engine.

Performance Gain:

Car will cool down again

Complementary Modification:

Change expansion tank, radiator hoses.

Maintaining the cooling system so that the engine does not overheat is a significant step toward getting engine longevity. There are many components in the BMW Z3 cooling system:

  • Radiator and coolant overflow tank.
  • Belt driven coolant pump bolted to the front of the engine block.
  • Belt driven fan attached to front of coolant pump. Viscous clutch controls fan speed based on engine temperature and rpms.
  • Electric (auxiliary) cooling fan attached to front of radiator. The cooling fan is controlled by the engine control module (ECM) via an output final stage.
  • Electrically heated thermostat.
  • Automatic transmission cooler or heat exchanger (if equipped).
  • Heater valve and heater core (for climate control).
  • Coolant level sensor inside expansion tank.
  • Coolant temperature sensor at cylinder head.
  • Radiator outlet temperature sensor
  • Coolant hoses and lines.

When the radiator begins to fail, you'll notice that the car tends to overheat at high engine speed, such as driving on the highway. When you accelerate, the engine temperature rises, and when you idle it returns to normal range. Now, this is not always indicative of a failing radiator, but a good starting point. 

The plastic side tanks of the radiator can crack, causing major loss of engine coolant. In that case you have to replace the radiator.

The radiator fins may also become plugged with debris causing the vehicle to run hotter than normal. This can be remedied by removing the radiator and flushing the fins with water.

In this article, I'll go over the steps involved with replacing the radiator on BMW Z3 models. Be sure to work with a cool engine and confirm the cooling system lacks pressure before opening the cooling system. On the Z3, the main difference in radiator replacement for the 6-cylinder is the lack of the expansion tank on the radiator.

Do not remove the expansion tank cap or work on any other part of the cooling system while the engine is hot. Coolant or hot steam may escape and will scald you. To do any work on the cooling system, wait until the engine has cooled off.

To avoid marring the paint and trim, work with a plastic prying tool or wrap a screwdriver tip with masking tape before prying out body or interior items.

Keep in mind that when your car was serviced before, parts may have been replaced with different size fasteners used in the replacement. The sizes of the nuts and bolts we give may be different from what you have, so be prepared with different size sockets and wrenches. 

Protect your eyes, hands and body from fluids, dust and debris while working on your vehicle. If you're working with the electrical system, disconnect the battery before beginning. Always catch fluids in appropriate containers and properly dispose of any fluid waste. Recycle parts, packaging and fluids when possible. Do not work on your vehicle if you feel the task is beyond your ability. 

Vehicle models change and evolve, as they grow older, so the vehicle shown in our illustrations may vary slightly from yours. If something seems different, let us know and share your info to help other users. Do you have questions or want to add to the article? Leave a comment below. When leaving a comment, please leave your vehicle information.

Drain the cooling system. See our tech article on cooling system draining and filling.

Remove the cooling fan shroud. See our tech article on radiator cooling fan replacing.

Working at the right side of radiator, disconnect radiator outlet temperature sensor electrical connector.
Figure 1

Working at the right side of radiator, disconnect radiator outlet temperature sensor electrical connector. (green arrow) Press release tab and pull straight off sensor.

Next; using a flathead screwdriver, loosen the upper radiator hose clamp.
Figure 2

Next; using a flathead screwdriver, loosen the upper radiator hose clamp. (green arrow) Once loose, slide hose clamp away from radiator, then disconnect hose by pulling straight off radiator fitting.

Working at lower left side of radiator; using a flathead screwdriver, loosen the expansion tank hose clamp.
Figure 3

Working at lower left side of radiator; using a flathead screwdriver, loosen the expansion tank hose clamp. (green arrow) Once loose, slide hose clamp away from tank, then disconnect hose by pulling straight off tank fitting. Then working at the bottom of the tank, unplug the coolant lever sensor (if equipped).

Working at the right side of the radiator, using a flathead screwdriver, loosen the lower radiator hose clamp.
Figure 4

Working at the right side of the radiator, using a flathead screwdriver, loosen the lower radiator hose clamp. (green arrow) Once loose, slide hose clamp away from radiator, then disconnect hose by pulling straight off radiator fitting.

Working at top of radiator support, unlock the plastic radiator mount by inserting a small flathead screwdriver, then press screwdriver down while lifting up on mount and pulling it toward front bumper.
Figure 5

Working at top of radiator support, unlock the plastic radiator mount by inserting a small flathead screwdriver, then press screwdriver down while lifting up on mount and pulling it toward front bumper.

Once you disengage the lock, open the plastic mount.
Figure 6

Once you disengage the lock, open the plastic mount.

Remove rubber seal from top of radiator by pulling up.
Figure 7

Remove rubber seal from top of radiator by pulling up. (green arrow)

Now you have to remove the two 8mm power steering cooler mounting fasteners.
Figure 8

Now you have to remove the two 8mm power steering cooler mounting fasteners. (green arrows)

Lift the radiator up slightly to expose the lower fasteners on the power steering cooler.
Figure 9

Lift the radiator up slightly to expose the lower fasteners on the power steering cooler. Then remove the two 8mm power steering cooler mounting fasteners (green arrows).


Once the power steering cooler is detached from the radiator, lift the radiator up and remove from the vehicle.

With the radiator removed, inspect the foam radiator seals (green arrows).
Figure 10

With the radiator removed, inspect the foam radiator seals (green arrows). If the seals are dry rotted or torn, replace them.

Next, transfer the rubber mounts from the bottom of the old radiator to the new.
Figure 11

Next, transfer the rubber mounts from the bottom of the old radiator to the new.

Then transfer all four power steering cooler speed nuts (green arrows).
Figure 12

Then transfer all four power steering cooler speed nuts (green arrows). Note: only top two shown, other two are at bottom of radiator.

Working at the side of the radiator, remove the coolant temperature sensor using a 22mm wrench.
Figure 13

Working at the side of the radiator, remove the coolant temperature sensor using a 22mm wrench. Then transfer it over to new radiator, be sure to replace sealing ring. (yellow arrow) Then transfer the upper rubber mounts to the new radiator. (green arrow)

Working at the left lower side of the radiator, remove the coolant level switch if equipped.
Figure 14

Working at the left lower side of the radiator, remove the coolant level switch if equipped. Use a 30mm wrench to loosen it, then unscrew by hand. Transfer over to new radiator.


With all the necessary parts transferred over to the new radiator, install the new radiator into the engine compartment. Keep it high enough to install the four 8mm power steering cooler fasteners finger tight. Once all four power steering fasteners are installed, tighten them. Then position radiator into lower rubber mounts. Then connect coolant level sensor electrical connector, if equipped.

Next reconnect the front plastic mounts.
Figure 15

Next reconnect the front plastic mounts. Press down on the mount until you hear it engage and it is tightly secured. If it will not lock, you will have to replace it.

Install the temperature sensor electrical connector.
Figure 16

Install the temperature sensor electrical connector. Sometimes, I find the connector will not fully seat and this prevents it from locking onto the sensor. What I do when this happens is I add some dielectric grease to the electrical connector seal (green arrow). Then press the connector on and until I hear the lock engage. Check that it is properly locked by trying to pull it off.


Connect all three radiator hoses and tighten hose clamps. Install cooling fan shroud, and fill and bleed cooling system. Once complete, check cooling system for leaks and top up cooling system.

Bookmark and Share

  Search our site:    

View Cart & CheckOut | Project List | Order Status |  Help    

 

[Home] [Customer Service] [Shopping Cart] [Privacy Statement]
 [Contact Us] [About Us] [Shipping] [Map to our Location] [Careers]

Copyright © Pelican Parts Inc.

Page last updated: Sat 12/3/2016 02:07:22 AM