Wiring diagram

Is there such a thing as the old style diagram for a 75/76 2ltr type 4? I can't understand the new style ones at all. I've got the old style diagram for the 72 which is is similar. Little things are different like I have the wipers on a stalk and I'm not sure what to do with the handbrake warning light switch, and a few other bits. If anybody has one I'll be eternally grateful

 

I don’t think they did the “van style” for later Bays. They were all current-path style. Not too hard to understand.

Might be worth looking on www. Vintagebus.com anyway.

 

This 72 on one has most stuff on it...

 

True. They didn’t change much basic stuff/colours over the years.

 

I don’t think you’ll find an old style diagram for your bus but if you’re looking for specific items Speedy Jim has schematics on his website that are easy to understand. http://www.speedyjim.net/htm/elec.htm
http://www.speedyjim.net/schem/wiper.gif
http://www.speedyjim.net/schem/2brake.gif

 

Thank you @Deefer66 , yes that one has a few more bits than the one I found. My wipers on a stalk rather than a switch doesn't make much difference. I still can't find the handbrake warning light switch anywhere though. Not quite sure how to splice it in with the brakeswitch warning light - presumably ok to just add it in as an alternative switched earth?
Thanks @77 Westy , some useful bits there.
@snotty - nope can't get to grips with the current path style diagram! Not to worry, I'm going to have a bash at drawing my own from the '72 version and bits that I've added - will make a change from watching Marmitee movies at night

 

Mork, I had a look but can't find the 74 in old style - did you mean it was there but in current path style?

 

The handbrake warning light has nowt to do with brake light switch. Have a look on vintagebus for a wiring diagram for one of the late US busses - should show the switch and the small module driving the “B” light on the dash. The handbrake switch connects to this, from memory.

The current path diags are pretty easy to understand once you get the hang of them, clearer in fact than the “mess of wiring” diagrams. They just split the wiring into functional areas, labelled along the bottom. The +ve or fused supply runs along the top, the ground’s at the bottom. Current paths flow from top to bottom. Easy, peasy, no prob for a man of your calibre

 

Ok I'll have another bash at trying to read the new-fangled modern version.
The "B" red light on the dash has 4 terminals - isn't it dual purpose - i.e. brake light switch warning and handbrake?

 

It is, but the connections come from different sources: the brake pressure wiring from the two pressure switches on the cylinder, the handbrake warning (as if you didn’t notice two feet of greasy pole sticking out of the dash) from the switch on the h/b bracket. A diagram of a US-spec bus should show the connections (or I might have them somewhere). The little “B” module just contains a bulb, a transistor and possibly a diode to “OR” the two drives together, from memory. It’ s not exactly hi-tech.

 

Ok got it. Just wanted to confirm that the light is dual purpose. I can figure out the wiring I think, but if you have a little diagram of that circuit it would be very helpful indeed.

 

Thanks for posting that, I was just about to start looking for the diagram for mine!

 

Can't find my notes, but wiring diag says terminals on "B" switch module are:

15 - +12V via F11, (black)
31 - earth (brown)
61 - wire from handbrake switch (white/green)
"K" - wire from master cylinder brake switches (red)

 

Brilliant - thank you kind sir

 

Yes thank you Mork. Printed off an A3 sheet of the 72 diagram and made copious notes and alterations. Just got to redraw it and build a loom now!

 

Forgot you were knitting it yourself...