- 1,957
- 418
- 68
- Location
- Culver City, CA
A couple of weeks back I installed a HMMWV self-cancelling turn signal switch (Kit # AM General 57K3222). However, the cancelling ring would not properly mount to the conical base of the M35A3 type steering wheel on my truck. So, the self cancelling feature would not work.
This past couple of weeks I designed and fabricated an adapter for the cancelling ring. I used a 3" PVC pipe union, three 11/32" L #6 stand-offs, and three 1 1/4" #6 machine screws, nuts and lock washers.
Using the cancelling ring, the union and some graph paper, I drew out a template for marking the drilling and cutting points. The PVC union was marked from the center line at 112º for cancelling ring and at 120º intervals for the wheel attachment points. The union was cut perpendicularly, to approximately 1 1/4" to 1 1/2"so as once the cancelling ring was installed on it the ring would touch the base of the steering wheel. A notch to correspond with the cancelling ring was cut out 180º from center line. This notch allowed for the entire assembly to slip over the steering column when attaching to the steering wheel hub.
Holes were drilled for the cancelling ring. The ring was mounted using the stand-offs and the screw, nuts washers mentioned before. The whole assembly was painted flat black.
The centering pins, the two long thin ones, were not needed for the installation, so I removed them. I ensured the steering wheel was at top center for straight driving. I like to mount my signal levers at a higher angle, so I made sure the cancelling pins were each at 90º to the lever center line at that orientation. If the adapter ring center line screws are aligned with the turn signal lever, then the pins are at 90º. This is important as disoriented cancelling pins may jam the cancelling switch rendering the switch lever inoperable. The rubber material on the steering wheel was soft enough for the kit supplied screws to self tap. Some steering wheels will require pre-drilling.
I took the truck for a spin and it worked perfectly. No more 5 mile blinkers! I also like this turn signal switch much better as the lever travel is much shorter that the standard switch.
Mind you, this mod is for the conical shaped hub steering wheels. If you have the type of steering wheel with the cylindrical hub, like on most M939-series trucks, you'll only need a simple screw and stand-off installed in the back side of the hub to cancel this type of switch.
This past couple of weeks I designed and fabricated an adapter for the cancelling ring. I used a 3" PVC pipe union, three 11/32" L #6 stand-offs, and three 1 1/4" #6 machine screws, nuts and lock washers.
Using the cancelling ring, the union and some graph paper, I drew out a template for marking the drilling and cutting points. The PVC union was marked from the center line at 112º for cancelling ring and at 120º intervals for the wheel attachment points. The union was cut perpendicularly, to approximately 1 1/4" to 1 1/2"so as once the cancelling ring was installed on it the ring would touch the base of the steering wheel. A notch to correspond with the cancelling ring was cut out 180º from center line. This notch allowed for the entire assembly to slip over the steering column when attaching to the steering wheel hub.
Holes were drilled for the cancelling ring. The ring was mounted using the stand-offs and the screw, nuts washers mentioned before. The whole assembly was painted flat black.
The centering pins, the two long thin ones, were not needed for the installation, so I removed them. I ensured the steering wheel was at top center for straight driving. I like to mount my signal levers at a higher angle, so I made sure the cancelling pins were each at 90º to the lever center line at that orientation. If the adapter ring center line screws are aligned with the turn signal lever, then the pins are at 90º. This is important as disoriented cancelling pins may jam the cancelling switch rendering the switch lever inoperable. The rubber material on the steering wheel was soft enough for the kit supplied screws to self tap. Some steering wheels will require pre-drilling.
I took the truck for a spin and it worked perfectly. No more 5 mile blinkers! I also like this turn signal switch much better as the lever travel is much shorter that the standard switch.
Mind you, this mod is for the conical shaped hub steering wheels. If you have the type of steering wheel with the cylindrical hub, like on most M939-series trucks, you'll only need a simple screw and stand-off installed in the back side of the hub to cancel this type of switch.
Last edited:
.