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Removal and Installation of Speedometer and Odometer
 
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Pelican Technical Article:

Removal and Installation of Speedometer and Odometer

Time:

2 hours2 hrs

Tab:

$200 to $850

Talent:

**

Tools:

10mm Allen socket breaker bar, 6? socket extension, 2' long 1? diameter pipe, flathead screwdriver, Phillips head screwdriver, 6mm socket, 7mm socket

Applicable Models:

450 SL R107 (1972-80)

Parts Required:

Speedometer and odometer

Hot Tip:

Disconnect battery

Performance Gain:

Working speedometer and odometer

Complementary Modification:

Replace other gauges

There are several reasons why the speedometer and odometer are not working. After you have established that the cable leading up to the instrument has not been severed, it is most likely the gauge itself. The replacement of the odometer by itself is not possible. While you could spend time sourcing out the gears that may have been stripped, chances are that the opportunity costs just don't make sense. It is easier and cheaper to replace the entire unit. For the sake of ethics and legality, you will want to set the odometer to indicate the proper mileage that the vehicle was driven while the odometer was broken.

In order to replace the speedometer and odometer unit, the instrument cluster has to be removed. Removing the unit, requires removing the steering wheel. This is a simple task if you use a breaker bar and a steel pipe to counter-act the force needed to loosen the 10mm Allen screw holding the wheel in place. It is estimated that there is greater than 65ft-lbs of torque holding the steering wheel in place. Without the leverage of a breaker bar and a pipe to counter-act the force you will have to use to loosen the screw. You will not be able to loosen it using conventional means.

Before you do any work on your car it is important that you wear safety glasses, work gloves and dispose of all fluids in a safe manner. Protect your eyes, hands and body from dust, debris as well as sharp objects and edges while working on your vehicle. Disconnect the battery before beginning work. Never work on your vehicle if you feel the task is beyond your ability.

Before the steering wheel can be removed, the sheering wheel pad must be removed.
Figure 1

Before the steering wheel can be removed, the sheering wheel pad must be removed. To do this, simply lift the pad off the clips holding it in place.

An alternative method to removing the steering wheel without removing the pad involves the removal of the emblem in the center in order to access the Allen screw.
Figure 2

An alternative method to removing the steering wheel without removing the pad involves the removal of the emblem in the center in order to access the Allen screw. If you do not want to remove the pad you can loosen the Allen screw. You will need to have someone hold the steering wheel in place as you attempt to loosen the Allen screw. Removing the emblem is easy and done so by lifting it off with a flat face screwdriver. 

Once the pad is liberated from the wheel, simply lift it off the clips.
Figure 3

Once the pad is liberated from the wheel, simply lift it off the clips.

Once the pad is removed you will have access to the lead for the horn switch.
Figure 4

Once the pad is removed you will have access to the lead for the horn switch. Disconnect the lead from the wheel.

Slide the pipe through the steering wheel as pictured.
Figure 5

Slide the pipe through the steering wheel as pictured. This will help to provide leverage when loosening the Allen screw. Using a 10mm Allen wrench with a six-inch extension on the breaker bar. If you line up the breaker bar with the pipe, simply force the breaker bar down as you pull the pipe up. Using equal force will allow you to loosen the screw without turning the wheel. After the screw is removed, the steering wheel can then be removed. 

Once the steering wheel is removed, the instrument cluster can be removed by lifting the top edge.
Figure 6

Once the steering wheel is removed, the instrument cluster can be removed by lifting the top edge.

Once the top edge is lifted up, pull the instrument cluster forward.
Figure 7

Once the top edge is lifted up, pull the instrument cluster forward. There will be several cables attached to the instrument cluster.

The speedometer cable is attached to the instrument cluster with a cable screw.
Figure 8

The speedometer cable is attached to the instrument cluster with a cable screw. Unscrew the cable from the back of the instrument cluster.

The back of the instrument cluster has a few other cables that are various indicator lights and fluid level indicators.
Figure 9

The back of the instrument cluster has a few other cables that are various indicator lights and fluid level indicators.  

Disconnect the tachometer lead.
Figure 10

Disconnect the tachometer lead.

Disconnect the sensor indicator.
Figure 11

Disconnect the sensor indicator.

There is a plastic part that has to be installed prior to fitting the instrument cluster.
Figure 12

There is a plastic part that has to be installed prior to fitting the instrument cluster.

After the Instrument panel has been removed, flip it over and expose the back.
Figure 13

After the Instrument panel has been removed, flip it over and expose the back.

Using a 6mm socket, remove the screws holding the tachometer to the back.
Figure 14

Using a 6mm socket, remove the screws holding the tachometer to the back. You will need to remove the tachometer / clock unit to remove the gauges.

There will be several screws that will have to be removed.
Figure 15

There will be several screws that will have to be removed. Make sure you do not lose any. They are difficult to replace.

The instrument cluster wires are held on by a plastic harness.
Figure 16

The instrument cluster wires are held on by a plastic harness. Take care in removing the plastic harness from the housing.

The light dimmer switch can now be removed.
Figure 17

The light dimmer switch can now be removed. It has to be removed in order to free the wires.

The unit can now be removed and replaced.
Figure 18

The unit can now be removed and replaced. The mileage can be adjusted on a new unit. Installation is the reversal of removal.

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Comments and Suggestions:
Bob Comments: This is very helpful and the pictures make it easy to understand. Thank you for the instructions.
September 9, 2015
  Followup from the Pelican Staff: Thanks for the feedback. Glad we could help.
- Nick at Pelican Parts
 

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