Series 3 Headlight switch assembly

Hi, Guys. It’s been quite a while since I roamed these forums and here I am.
I’m into my second headlight switch and the plastic (Bakelite?) surrounding the 2 mounting bolts have split and crumbled away. After some searching, I found another used unit that was complete but close inspection showed that hairline cracks were already there. Has anyone come up with anything to reinforce the bolt surrounds or any other solution to this problem?

DAC3089

Hi Fazal,

If the switch cover doesn’t line up correctly with the dash, when you tighten the screws it puts a lot of force on the cover and eventually will crack.
I had to add a couple of washers between the cover and the mounting bracket on mine.

Hi Fazal,
it is likely not bakelite. Mine aren’t. The brass nuts are probably melted in, right? It should be a thermoplastic.

Maybe you can use some thinner or plastic glue (Revell or so, but it’s thinner just the same) in areas that you can’t see (tape off the rest so it doesn‘t stain) so the cracks close up again. You can also, likely, weld it with plastic. It is important that the cracks can’t continue. And don’t overtighten.

Hi Fazal,

as there is no load whatsoever on the headliight switch surrounds the fixing bolts are simply meant to keep it in place, not more. So really, finger-tip-tight is enough.

From the feel of the parts I doubt the plastic is thermoplastic. Very easy to check: put some plastic model building cement, as David described, in from inside. If it works it will virtually weld the crack. If it doesn’t you can only try to reinforce with another peace of something glued in from inside with a contact cement, possibly a polystyrole contact cement.

Good luck

Jochen

75 XJ6L 4.2 auto (UK spec)

I’ve usually had good luck repairing plastic bits with thin (.020" or so) shim stock and JB Weld, with the shim material used to bridge the crack…acting as a sort of stitch, if you will.

Good used surrounds shouldn’t be that hard to find with a little patience. The black-faced style are certainly more easily found than the silver, though.

Cheers
DD

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When I dropped the shroud to get at the ignition switch in my car, I busted some posts.
Got one to stick with one of the glues in my collection. Which? Forgot. And, a bit f black duck tape on the black is not easily noted.

I replaced the slotted screws with Allen heads.

Now that’s a great tip, especially on the steering wheel surround, I’m still wondering what they were drinking when they didn’t specify crosshead screws there.

I have also, somewhat successfully, melted the parts together with a soldering iron and some black plastic.

That’s what I meant with thinner/ revell glue. Another option might be pur glue, but that’s a bit overkill.

Thanks, Guys. I’ll do a bit of research into the glue/reinforcing , I think a combination of both might be the way to go.
Cheers
Fazal

Thanks for that. (I think my knee knocking it every now and then didn’t help either)