Bulb holders; intermittency.

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MIG Wielder
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Bulb holders; intermittency.

#1 Post by MIG Wielder »

I reckon the worst thing to fail an MOT test on is an intermittent bulb-holder. Particularly at the back.
This seems to be a particular problem on cars that are not used very much; simply because the heat from the bulb in use tends to drive out moisture.
Replacement is one solution, and these bulb holders are the same as those fitted to the Spitfire, the Stag and also some Lotus models from the '70s. The Stag Owners Club always have lots of them on their stands at the Shows at a good price but I recently helped to work on a Sprint on which there was nothing lighting up at the back. In this case each bulb-holder's terminals, the connectors, the internal spring connectors all needed cleaning out before it worked.
There was one reversing light which proved to be much more of a problem than the others. The bulb by itself was O.K., the bulb connected across the wiring was O.K.; the contact springs were clean but it still refused to work.
The problem is in the design; the side copper contact that touches the bulb runs up the side of the holder and ends up under the plated mild steel of the surround. If moisture gets in here it corrodes and isolates this ground contact.
Solution: scrape the copper and mild steel clean and run a film of solder between the two. Surprisingly the mild steel solders quite well.
Sorted!
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Mad Mart
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Re: Bulb holders; intermittency.

#2 Post by Mad Mart »

:thumbsup: Exactly what I do Tony. I got fed up with trying to get a good connection.
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Richard the old one
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Re: Bulb holders; intermittency.

#3 Post by Richard the old one »

Hi Tony.

I have started to draft what Steve is going to call Richard Old's A to Z on dolomites for inclusion in Dolly mixture in which I will attempt to give tips etc that I have picked up over the years. Will it is o.k for me to include this advice which is something new as far as I am concerned.

Richard
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Re: Bulb holders; intermittency.

#4 Post by new to this »

Thats a good idea
MIG Wielder
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Re: Bulb holders; intermittency.

#5 Post by MIG Wielder »

Richard the old one wrote: Fri Apr 27, 2018 8:56 pm Hi Tony.

Will it is o.k for me to include this advice which is something new as far as I am concerned.

Richard
Hi Richard, Yes, no problem please do use this if it helps.
Cheers for now,
Tony.
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tony g
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Re: Bulb holders; intermittency.

#6 Post by tony g »

Great tip Tony, will a decent soldering iron be good enough to solder to the steel ring?

Cheers

Tony
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MIG Wielder
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Re: Bulb holders; intermittency.

#7 Post by MIG Wielder »

Hi Tony, I have a 25W Weller TCP1 with a selection of bits. That manages just fine. I tin the mild steel bit first with cored solder and scraping the steel with the point of the iron under a pool of flux and solder, and then when its tinned nicely I run a small fillet of solder down onto the top of the copper contact.
Tony.
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tony g
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Re: Bulb holders; intermittency.

#8 Post by tony g »

Thanks Tony,I'll try on a couple of spares I have :thumbsup:

Tony
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