Morris Minor Owners Club

hi all i have seen a reversing light swith to go on my 1098cc gearbox http://www.ebay.co.uk/itm/lucas-SMB462- ... 45fec2d368 so how do i go about wiring it up

cheers josh

The tricky bit will be getting the switch positioned so when you put the gear stick into reverse it hits the switch.

Once that is done, take a cable from the same connection as your front/rear lights at the board under the bonnet, feed the cable to the switch, from the other side of the switch feed the cable to your reversing light, then come from the light on the negative side and join the cable to the body work somewhere.

Some would say, just fit a switch on your dash and remember to flick it on and off.

i just wanted the switch on the gearbox so it would light up as soon as i go in reverse

I'm not sure they are that clever Josh. I think there was probably a small flat lug on the gear lever under the floor. The switch may have bolted to a bracket on the gearbox in a position so when you are in reverse the lug presses the switch down. When you come out of reverse the switch is released.

I could be wrong though... brake lights are done the same way even on modern cars, except they are fitted to the brake pedal.

Thats the reversing light switch that came with the Midget gearbox. I fitted the MG 1100 gearbox remote housing to my Minor gearbox. It has the correct drilling for this switch. If you can find one of those then its a simple mod and works well.

Al

I don't see any mention in the list of cars that it fits - of the Morris 1000.......... Maybe it will fit - maybe not.

It would be nice if it would fit but I don't think there is anywhere to fit it on a Minor gearbox.
This might give you another idea. I'm currently in a test phase of this modification.[frame][/frame][frame][/frame]
This sits on top of the reverse selector plunger, that moves up when reverse is selected, and activates the switch as shown.[frame][/frame]
In forward gears and neutral[frame][/frame]
and in reverse[frame][/frame]
So far so good, it has been reliable, with a test light in the car.
The good thing I find with this setup is that it all fits under the rubber gear lever boot and wasn't that hard to do although it was a bit fiddly getting the switch lever adjusted correctly.
The actual bracket is a corner brace from a hardware store.

That's the best looking way of fitting a reversing switch I've seen.
Nice job!

Nice job - what is the rating of the microswitch? 1 reverse light bulb will draw 2A, 2 obviously 4A! Probably need to run through a relay?

I would not take the supply from the lighting circuit, otherwise if you need to leave the sidelights on when parked and you also leave it in reverse, the reverse light(s) will be on as well! I would take it from an ignition switched supply, and have a fuse in it as well.

X3 on the nice job Roni and I agree entirely on using a fused supply from ignition circuit and a relay.

The advertised switch will fit a 1275 Midget box which has the threaded hole on the remote gear shift extension, not on the Minor box

The switch (5A) earths a relay which has its power, and the power for the light, taken from the ignition supply via its own fuse. This way there only need to be one wire run to the switch. The relay is hidden in the empty control box. Finally found a use for that space!
My only question with this setup is how it handles moisture/grime etc. That, and how will it handle vibration.

Roni, that is an exellent piece of work. Josh, I'd follow this example!

Roni,

Completely off topic, but following problems with breaking 2 wheel centres earlier this year after 40+ years on the car, I will be replacing them will 'Minilite' style alloys. What size, width and offset are the wheels and what tyre size are on your Minor?

14x6 Performance Superlites 12P ( more details at http://www.performancewheels.com.au/Hom ... at=Classic ), 175/70x14 tyres
The 6" width was the only one available here at the time. A 5" or 5 1/2" would have been a better fit.
I know what you mean about the steel wheel centres breaking. A long time ago I had one front wheel shatter right in the middle of town outside the railway station.

Roni,

Thanks. The current steel wheels are 13" x 5.5" and I have to decide 13" or 14", then either 5.5" or 6" wide! And I don't really want alloys in the first place, but after having 2 break there is no other choice. Have to decide soon though.

My version is very similar:
http://www.mmoc.org.uk/viewtopic.php?f= ... ng#p268752
The microswitch rating is 250V 6A so I fitted a relay.
As Roni mentioned above it's a bit of a fiddle to set up but works fine.
Regards
Declan

Declan_Burns wrote:...
The microswitch rating is 250V 6A so I fitted a relay...

So if the reverse light is (say) 21W @ 12v = 1.75A then why the relay?...or am I being fick (as usual )

It's all to do with 'inrush' current. The resistance of the filament inside the bulb is much lower at ambient temperature than when it is at its operating temperature - typically the difference is 10-15 times. So taking a single 21w 12v bulb, which draws 1.75A when 'on', it would draw 10-15 times that for the first few milliseconds when switched on.

A 5A switch will last for a while, but is likely to have a rather short life, so using a relay will give it a much easier time.

IslipMinor wrote:It's all to do with 'inrush' current. The resistance of the filament inside the bulb is much lower at ambient temperature than when it is at its operating temperature - typically the difference is 10-15 times. So taking a single 21w 12v bulb, which draws 1.75A when 'on', it would draw 10-15 times that for the first few milliseconds when switched on.

A 5A switch will last for a while, but is likely to have a rather short life, so using a relay will give it a much easier time.

Exactly!
Regards
Declan