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MG MGB Technical - Lights Out

I have a 67 MGB that has a bad headlight switch. It is the pull type switch that appears to be used only two years in North America. Both Moss and VB list the switch as not available. Does anyone know of a substitute switch that I could use and still retain the original knob.
Jim Lema

Jim, look up Item number: 2447221675 on e-bay. It might be what your lookig for.
K.G. Martin

Hi Jim.

I don't know of an alternative, but it might be possible to find a good second-hand switch if you do some searching.. alternatively, it might be possible to repair the old switch, maybe by something as simple as soaking it in WD40 and then operating it a few times.

HTH.. Don
Don

Please do soak electrical switches (or any other electrical device) in WD 40 or even spray any of it into the switch. WD 40 is used as a preservative for metal plates and a water displacement product (hence the WD in the product name). Being silicon, it is an insulator and will not enhance the conduction of the contacts. Any of it that is left in the switch will get gummy over time and collect dust and dirt and cause problems you do not want to have to deal with in the future. If you want to try rejunivating your switch, go to Radio Shack or other electronics supply house and get some contact cleaner/lubricant (Cramalon comes to mind if it is still made) and use it to try and clean up your switch's contacts. This may or may not work, but it will not leave you with a gummy mess that gets progressively worse as time goes by. Good luck - Dave
David DuBois

Jim;
I ran into this problem on my 67 roadster 10 years ago. Instead of replacing the faulty pull switch a same type unit, I used an older style toggle headlight switch. The wires plug right in with no mods required. One thing that I altered was the location of the washer pump. This I swapped with the headlight switch so it looks like the early cars original setup. Hope this helps. Ray
Ray

My 67, whoops 66, uses the toggle switch which I like better as you can instantly tell if your lights are on and all those toggles look nice together.

Radio Shack sells an aerosol switch cleaner.
Mike MaGee

Looks like the toggle switch may be the way to go. The knob on the pull switch was looking poor anyway. I was thinking of putting relays in the wiring to take the load off the switch. Can you use the typical headlight relay with a positive ground car? I am not interested in changing the ground as I have a good original radio and the tach would need to be rewired. I built a electronic voltage stabilizer and it needed different parts for positive ground. Not sure it that is true for relays.
Jim Lema

just looked up the MSDS, Material Safety Data Sheets for WD-40.... it's not silicon, nor does it contain silicon. The active ingredients are Aliphatic Petroleum Distillates, petroleum base oil and Hydrocarbon Fluid. It is because of these oils that it should't be used. The oils will attract dust, dirt and other non-conductive things. Silicon is the main ingredient in dielectric grease, it's used in semi-conductors,transitors and other various electronic things, it does conduct electricity.
waitaminute

Jim slide by your local NAPA and look in their catalog, the one that shows pictures along with aplications and specs. I bet you can find a switch that will work for you.RIC
R E L Lloyd

Unless you get a relay with an integral diode to suppress the back emf, which I haven't come across for auto use, you can connect the winding and contacts either way round i.e. it is suitable for either polarity system. I did think of suggesting relays anyway if it was just a matter of the pull-switch getting hot in use. As you indicate you will need two relays - one for dip and one for main beam - which will protect the dip-switch as well as the main lighting switch. You should really fit fuses as well while you are at it, but a single fuse could cause complete failure of the headlights so I have used one fuse per filament i.e. four fuses in all, a 4-way blade-type fuse holder is ideal, 15 amps each is plenty. The 12v supply to the relay contacts should come from a brown wire, which to be even safer could have its own in-line fuse, but this would need to be 30 amps. If you mount these and the relays immediately behind the radiator shroud you can make up a short loom to bring the feed to the relays back from the connectors by the right-hand headlight and back again to the headlights which avoids cutting into the loom. http://www.mgb-stuff.org.uk/wn_electricsframe.htm and click on 'Lighting' and 'Uprated headlamps - Relays and Fuses' for schematics.
Paul Hunt

About a year ago I bought two new headlight pig tails and two relays. I have installed the pig tails, but never got around to the relays. The pig tails were to replace a dodge that the DPO had done. He had taken both wings off the car and just cut the wires between the headlight bucket and the radiator. He was to lazy to disconnect the wires. He put them back together with crimp fitting and left them exposed under the wheel well. Didn't think about polarity when I bought the relays. Since I am getting a new switch it appears a good time to install the relays. Thanks to Paul I don't need to search for new relays.

Jim
Jim Lema

waitaminute in USA - I stand corrected regarding the silicon in the WD 40. Regardless, it still makes a mess of electrical items (and clocks also). Cheers - Dave
David DuBois

Paul's recommendation for using separate fuses for each headlight filament is a great way to go. I have just implemented it on my A. After I bought the separate fuze holder I came across relays that have a blade type fuze included. Would allow relay installation without a separate fuze box. A web search for "auto relays" should locate them.

FWIW

Larry
Larry Hallanger

Paul...

Try

http://www.vehicle-wiring-products.co.uk/VWPweb2000/relays/relays.html

HTH.. Don
Don

Well yesterday I got a can of contact cleaner at Radio Shack and gave it a try on the switch. As of now the switch does work. However, I still plan to go ahead with the relays. The cleaner was alot cheaper than a new switch.
Jim Lema

This thread was discussed between 10/12/2003 and 14/12/2003

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