356C Teardrop light Screw

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EricMcKinley
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356C Teardrop light Screw

#1 Post by EricMcKinley » Sat Nov 16, 2019 5:08 pm

I was tightening the rear teardrop light this evening and probably tightened one of the screws a little too much.

I think i threaded the screw a little, it now wont tighten.

I may have to place a slightly larger diameter screw in this one side to allow me to tighten to make a seal with the rubber gasket.

I have looked on the PET and cannot see a size for this screw.

It is called a cross recess screw, part number: 644 631 471 00.

Does anyone know the actual size of this screw.

Thanks in advance.

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Mike Wilson
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Re: 356C Teardrop light Screw

#2 Post by Mike Wilson » Sat Nov 16, 2019 6:07 pm

I just pulled one off my car.
M5, oval head, countersunk, chrome, Phillips head
12mm overall length; 9mm threaded portion
10mm across the head

If someone has the definitive size with the German numbers, please weigh in.

Mike
Mike Wilson
Lomita, CA
'63 B coupe

Hugo Karasawa
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Re: 356C Teardrop light Screw

#3 Post by Hugo Karasawa » Sun Nov 17, 2019 12:19 am

These are pictures of the original oval head screw.
It is an M5 screw, total length 13.5mm, it is an M5 x 12mm oval hrad.
Most probably you stripped the threads on that side, you can repair it using an M5 rivnut (pictured), similar to the nut used in the light housing.
Or use some solder to repair the threads.
oval head screw 01.jpg
oval head screw 01.jpg (126.32 KiB) Viewed 402 times
oval head screw 02.jpg
oval head screw 02.jpg (136.81 KiB) Viewed 402 times
oval head screw 03.jpg
oval head screw 03.jpg (205.44 KiB) Viewed 402 times
oval head screw 04.jpg
oval head screw 04.jpg (136.2 KiB) Viewed 402 times

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EricMcKinley
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Re: 356C Teardrop light Screw

#4 Post by EricMcKinley » Sun Nov 17, 2019 2:51 am

Mike, Hugo, thank you very much for the replies and taking the time to remove the screw and measure.

I believe I stripped the threads in the light section not the actual screw itself.

Placing an oversized screw probably is not the best option, repair would be better.

You mention solder, can you elaborate a little, also are there any other ways to achieve a fix that others may have used in the past.

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Mike Wilson
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Re: 356C Teardrop light Screw

#5 Post by Mike Wilson » Sun Nov 17, 2019 11:55 am

I believe Hugo is suggesting drilling out the threaded portion on the tail light to insert a 5mm Rivnut. Another option might be to fill in the threaded portion with solder or JB Weld and then drill and tap it back to 5mm.

Mike
Mike Wilson
Lomita, CA
'63 B coupe

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EricMcKinley
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Re: 356C Teardrop light Screw

#6 Post by EricMcKinley » Sun Nov 17, 2019 12:06 pm

Mike, yes your right, I will look at that option, thanks Hugo.
I wasn’t aware that JB weld was hard enough to drill and tap, another definite option.

Thanks guys.

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Re: 356C Teardrop light Screw

#7 Post by Hugo Karasawa » Sun Nov 17, 2019 1:01 pm

Yes, that is what I meant. There is not much force in that place, it is just to hold the chrome bezel.

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Bob Kittel
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Re: 356C Teardrop light Screw

#8 Post by Bob Kittel » Sun Nov 17, 2019 1:14 pm

In my opinion Marine-tex makes the best fillers for metal repairs. Use the Marine-tex gray and you can get it a marine dealer or Amazon. Threads, taps and machines like metal. Maybe overkill for this repair but nice to have in the tool box.
Bob Kittel

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EricMcKinley
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Re: 356C Teardrop light Screw

#9 Post by EricMcKinley » Thu Nov 28, 2019 9:42 am

I used JB Weld, leaving it for a few days to fully harden.

I drilled and tapped it to 5mm, and inserted the screw.

I could not pull the screw back out, as before, so a workable solution.

Many Thanks for all the help and advise guys.

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Mike Wilson
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Re: 356C Teardrop light Screw

#10 Post by Mike Wilson » Thu Nov 28, 2019 12:44 pm

Congrats on solving the issue, Eric.

Mike
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Thomas Sottile
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Re: 356C Teardrop light Screw

#11 Post by Thomas Sottile » Mon Dec 02, 2019 10:26 pm

If you can get a 5mm oval head screw about 1/2 inch long or 5/8 long you can make your own

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Re: 356C Teardrop light Screw

#12 Post by Thomas Sottile » Tue Dec 03, 2019 12:51 pm

good solution

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