#Laycock overdrive solenoid manual

It's a fit of a frankenstein car having a Laycock 4 syncro OD box (with dipstick) and has a loom from a 71 car in it. The other side of the switch goes to the solenoid, probably yellow/pink. That goes to one side of the overdrive switch (left of gearbox).

#Laycock overdrive solenoid manual

In which case yellow comes from the manual switch, out of the main harness and to yellow/red in the gearbox harness by the fusebox. But if you are fitting OD for the first time that shouldn't be there. Your overdrive is complicated by being a 66 car, which would have had a D-type overdrive with vacuum switch and relay. The other side of the reverse light switch has green/brown, the other end of which goes to green/brown in the rear harness, again by the fusebox. Green is fused ignition, comes from the main harness by the fusebox, and goes to one side of the reverse light switch (right of gearbox). For those of us who are 'electrically challenged' that makes life much easier. If you have such a switch, simply run power from the white wire circuit (activated when the ignition switch is on) to the switch, thence to the overdrive inhibitor switch, then to the overdrive solenoid.Д®xpanding the factory wiring diagram (most copy shops here offer such a service for a nominal fee), then laminating the enlarged diagram, allow you to use a dry erase marker to trace out circuits. You might check out, or someone may post, what switch was used with the Mark I series. My 68 GT had the switch on one of the stalks and my original 79 had the switch on the gearshift knob. I do not know what was the switching mechanism for the Mark I MGBs. With my two 79s and my daughter's 77, I simply spliced into the white wire circuit and ran a wire to the in-line fuse, then to a dash switch, then to the overdrive inhibitor switch, then to the overdrive solenoid. Most of us add an in-line fuse between the power source and the on-off switch (something the factory did not do) as a precaution. Basic wiring of the overdrive is a power wire to a switch, from the switch to the overdrive inhibitor switch on the transmission, thence to the overdrive solenoid. Not sure what the photo was as I had no reference. I'm sure others will clarify for you.ДЄndrew. There may be additional elements to the 71 loom I don't have on mine. There may be two spades on that green to the reverse light switch - one power in and the other power back? In which case there are two connections in the amalgamation of wires for that green wire set run.

Hope both that I am recalling correctly and that this helps.ДЄndrew, just had a 'thought'. The mounting bracket (holding your wire set together)I attached under one of the extension mounting bolts, RHS I think, but could be positioned where best fits on your unit. With a 71 loom and a 66 box (assuming of course that nothing has been substituted) I suspect you may not have the reverse lights so not need the green. Other end to the yellow from the dash mounted OD switch in that amalgamation of wire ends in the RHS rear corner of the engine bay.ДЄ two ended extension piece (attached to that) has a spade which connects to the remaining terminal on the cutout switch and a bullet end that connects to the internal solenoid wire that emerges from under the OD itself.ДЄ green wire spade end connects to the reverse light switch on the left hand side top of the extension housing and to a green feeding those lights in that amalgamation of ends in the engine bay. Happy for anyone to correct me if needed.ДЄ green/yellow wire with end spade connects to the OD cutout switch on the top right hand side of the extension housing. The loom in the car is a 71 just to confuse things further.ДЇrom memory, on my 69 CKD local production. Oh and why have I got three wires in one section where there can only be two terminal that it attaches to. I've got dyslexic reading the wiring diagram and can't fathom it out, so if anyone has got a photo of there set up or can simply describe what goes where then I'll be a happy chappy. So it all came as bags of bits and pieces so I have no reference as to how it was fitted initially.

I'm fitting it to the 66BGT I've got (or should it was being fitted by previous owner who got stalled with the project and I took it on instead). Which wires go where on a 4 syncro OD box. MG MGB Technical - Overdrive Wiring? Confused of Holmfirth here.