The angle drive is the first stage of the speedometer system, transferring the rotary motion of the front left wheel to the speedometer. This also runs the tripometer and odometer, which are part of the speedometer unit.
The angle drive part of the speedometer chain consists of two parts, the angle drive itself, and the so-called dust cap.
Angle Drive Edit
The angle drive is mounted on a large nut behind the front left wheel. A long, flexible spindle with a squared head runs through the wheel and into a squared hole in a small plastic dust cap. When the wheel turns, the dust cap spins the angle drive's spindle. This motion is then rotated 90° through a set of gears to the lower speedometer cable, which runs through the firewall and into the Lambda counter, and finally the speedometer itself via the upper speedometer cable.
The angle drive is also referred to as the 90° speedometer adaptor in the DeLorean documentation.
- Part Number: 106130
Dust Cap Edit
The dust cap is a slightly domed, yellow plastic disc about two inches in diameter with a squared hole for the angle drive spindle. It is held in place through the pressure of the mounted front left wheel. The name "dust cap" is misleading, as it is in fact an integral part of the speedometer system, and the speedometer will not operate without it. The only reason that the angle drive turns is because its spindle is notched into the square hole in the dust cap.
The dust cap is also referred to as the adaptor cup.
- Part Number: 105104
Angle drives should be lubricated at least once a year, and preferably at every oil change.
The newer angle drives from DeLorean Motor Company have a grease fitting, allowing the angle drive to be lubricated with a standard grease gun. The lower speedometer cable does not need to be disconnected on this model.
Both models are lubricated with SAE 80 or 90 gear oil. Grease should not be used on the angle drive.
See the Speedometer Troubleshooting for information on diagnosing angle drive and dust cap issue.
Replacing the Angle Drive and Dust Cap Edit
Tools Required Edit
- Socket wrench [need more detail]
- Wrench [need more detail]
- Vice grips or or pliers
- Flathead jewelers screwdrivers
Parts Required Edit
- New angle drive
- New angle drive retaining clip
- New dust cap (if your old one is damaged)
Removing the Angle Drive and Dust Cap Edit
- Turn the steering wheel all the way to the right. This will provide easier access to the angle drive. You may find it easier to do this after removing the tire.
- Jack up the car and remove the front left tire.
- Remove the dust cap. This is the yellow plastic disc in the center of the hub. Simply pull it off straight.
- Loosen (but do not remove) the large nut in the center of the hub with a socket wrench[need more detail].
- Reach behind the hub and find the large nut there. This is where the angle drive is mounted.
- Find the lower speedometer cable. This is connected to the angle drive and extends towards the back of the car and through the firewall. Disconnect it from the angle drive by twisting its connector counter-clockwise. Vice grips or pliers may help here.
- Remove the large nut on the rear of the hub with a wrench[need more detail]. You may need to turn the steering wheel to get better access.
- Extract the angle drive from the back of the hub.
The Angle Drive and the Nut Edit
The angle drive now needs to be separated from the large nut. It is held in place with circular retaining clip. The clip can be rather difficult to spot, in part due to all the grease in the nut, and especially so the first time you do it. You can use a small flathead jewelers screwdriver to pry one end of the clip out, and then run a second one around the clip, between the clip and the notch it is in, until it pops free.
Another technique is to hold the nut in a vise then compress the clip into the groove with two screwdrivers and then use a drift to eject the drive from the nut.
Once the old angle drive has been removed from the nut, you can insert the new one and secure it with a new retaining clip. This is a lot easier than taking out the old one, as it snaps right into place.
It is much better to first reinstall the nut and torque it with a socket wrench and then install the drive into it ! Using a socket allows to use a torque wrench, if the angle drive is installed, a socket can't be used. The given torque is 165 ft.lb or about 225 Nm (approx 22 m.kg).
Before reinstalling it in the car, you should lubricate it per the instructions above. New angle drives usually come lubricated, and this may not be necessary in that case. Grease may be applied to the spindle surface just to keep it from rusting.
- Hand-tighten the angle drive nut onto the back of the hub
- Spin the angle drive around so you can re-attach the lower speedometer cable.
- Tighten[need more detail] the angle drive nut with the wrench[need more detail].
- Tighten the lower speedometer cable with vice grips or an adjustable pipe wrench.
- Tighten the nut in the center of the hub that you had previously loosened. The instructions for the newer DeLorean Motor Company angle drives suggest tightening it as much as possible, as this nut holds the wheel on the car.
- Mount the dust cap on the angle drive's spindle. The spindle should fit snugly in the cap's square hole.
- Remount the tire and lower the car.
Test Drive Edit
Take the car out and make sure the speedometer is working properly. If you are having problems, check the Speedometer System article for general troubleshooting tips.
Rebuilding Angle Drives Edit
Jack on DMCTalk posted about how he repaired his angle drive. His specific failure was related to the end of the spindle snapping off. He was able to repair the spindle with epoxy and then solder, but found that the angle drive would start to seize as he spun it. He disassembled the unit, cleaned it, and use some small washers to adjust the gear spacing.
In the same thread, DeLoreanChuck talks about how he repaired a broken angle drive spindle by welding on a cut and squared off a drill bit.
There thread includes pictures of disassembled and repaired angle drives.