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MG MGB Technical - OD Relay wiring for a 67

Hi All.

Working on the wiring for my soon to be installed D. Type overdrive.

I picked up the Moss harness and relay and have the vacuum switch.

None of my electrical diagrams clarify the relay.

Here is the marking on the relay

.
.
........... .
. __ __ . .
. W2 __ ...
. C1 .
. .
. __ .
. C2 .
. .
. __ ...
. W1 . .
........... .
.
.

Wires are

Black
Yellow (double wire on one terminal)
Yellow/Red
Yellow/Red (Heavier)
White

Also, what wire goes on the top of the vaccume switch. Yellow or yellow/red?

Where does the harness pass through the firewall?
Bruce Cunha

Diagram did not transfer as I drew it.

W2 is on the left side

C1 is a double terminal on the right

C2 is in the center

W1 is on the bottom
Bruce Cunha

Bruce - You have mail. Dave
David DuBois

C is contact W is coil, so probably stands for winding here. My factory manual shows W2 grounded, no colour but should be black. W1 control in is via the od switch and is Yellow, there is another yellow from this point to the vacumn inhibitor switch.
C2 is the White feed from the Fuse box. C2 is the y/r return from the vacuum inhibitor switch and another yellow/red going to the gearbox interlock switch, it does not concern you here but the wire from that switch to the gearbox is shown yelloe purple, although I believe on my car it is acually white.
Stan Best

Dave and Stan

You are the reason this forum is so great. Without this, it would have been trial and error to figure this out.

Stan

I noted that the wiring diagram showed a yellow purple that was not on the wiring harnes that Moss provided. Thanks
Bruce Cunha

Ok

Got the diagram and all the wires hooked to the relay.

Now, where does the OD wiring harness go from the relay through the firewall?
Bruce Cunha

I have some pics I will email u.
Stan Best

Oh, and one reason you are having trouble finding where the small o/d loom goes through the firewall is because it doesn't. The pics show you where it goes across in front of the heater and is P clipped, it then picks up the main loom near the pedal box on my RH drive car.
Stan Best

Thanks Stan

That makes sense. I know there are "extra" wires over in that area. I also found the ends that are under the dash.
Bruce Cunha

Stan,
Since I will soon be doing the same installation, would appreciate a copy of the email (with pics) that you sent Bruce. THANKS
Steve Buchina

This thread was discussed between 18/09/2006 and 19/09/2006

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