Hello. New here... I'm wondering if anyone has had to replace or repair the backup light switch on a manual 1978 240 Volvo? If so.. How did you do it? I have not been able to locate a new or used replacement part for this switch. Since I am a experienced 3D modeler (CAD) I went ahead and modelled a replacement switch that I'm currently thinking about having 3D printed. I will be replacing the spring and metal contacts as well. But first, I wanted to ask if anyone has found another solution? My switch is currently beyond repair itself.

The switch in question is a lever action type switch found bolted to a steel plate/bracket partially encircling the base of the car's stick shift. The steel plate/bracket has an arched ridge, which a nub/protrusion on the stick shift shaft rides along when shifting into reverse. This nub/protrusion engages the switch and turns on the backup lights. (Damn thing broke apart and off the steel plate/bracket. Its internal spring was also lost when it broke and I've since purchased a new spring.) Questions?

Attached is an image of the switch (Shown in two parts. Internals are broken as well.) and also shown is the metal plate it bolts to (Upper right in image).

BTW: This 1978 242GT is a restoration project.

Thank you.

 

Will the alternate switch that fits in the transmission top cover work?

https://www.ipdusa.com/products/2139...SABEgLdafD_BwE

 

@hoonk... I looked into this a while back and if I remember correctly my transmission does not have a port in its top cover for that particular type of switch. Now I am curious to check again, just to be sure. I actually have one of those newer switches on hand and it would be such a simple solution if it worked.

 

This is from the VIDA parts catalog

 

a 1978 is could easily be a M45 4-speed, rather than a M46 4+OD

 

Yes I had a 78 242, lovely rust color with a 4 speed - I built a m46 from spare parts and installed it, had a hard time finding the correct speedo drive gear for the diff that came with the 4 speed! - m45/m46 use the same top cover/reverse switch.

 

It is confirmed... My 1978 Volvo 242GT does not have a port on its transmission top plate for a backup light switch. I'm starting to think that Volvo only did this on a very few of their cars. Hence the difficulty finding a replacement switch. Looks like I will be printing a new custom switch.

BTW: My car is a 4-speed with overdrive (4+OD).

If anyone else runs into this situation with another Volvo please let me know. Thanks.

 

Here is a mockup of the switch in question, positioned on the metal plate...

 

note that consumer 3D printing, using PLA, is totally inappropriate in a car... parked in the sun on a hot day in the summer, cars can easily reach the temps were PLA turns to goo and sags.

now, if you hav eaccess to commercial 3D printing gear that works in sintered metals, thats another story entirely.

 

@pierce... Yes, I always intended to have these parts professionally printed. I haven't decided on the exact method of printing yet. I will consult with the professional shop on what would be best. I'm considering one of the methods that employs nylon. I'm well aware of the limitations of consumer 3D printing materials. Thank you.

 

My local Volvo junkyard has a used m45/46 top cover with a reverse switch in it for $45 or less, granted the trans probably has to come out to replace it. voluparts.com 404-352-3402

 

@hoonk... Thank you for the heads-up on a possible replacement top cover. However, it worries me that there may be more then just a new top cover needed. I worry that because my transmission has a flat top cover, and not a domed one, that the internals just aren't there for the backup light switch to engage with. I'll have to look into this further to understand why things are the way they are. For now, though, it appears that the most expedient thing to do is to replace the switch. I would hate to drop the transmission only to find out a top cover with the proper port wouldn't work anyway. I would need to somehow confirm that everything would work first. (I've had similar problems with a few other parts on this car. Strange.)

I'll check out voluparts.com for a few other parts I need as well.

 

I'd bet the left bump on #6 pushes the reverse lamp switch