volvo N12 help please

Hi, all . Im trying to put a volvo N 12 back together . its been like trying to do a pussle with out a picture . I have been told its a late 70s chassis with a late 80s cab . Almost done but im chassing a wiring diagram , a fuse and relay box diagram , also a diagram for the plug board and a diagram for brake pneumatic lines as the truck has had many cowboys work on it and they have gone the hack with cutter on bothe systems and mixed every thing together. I believe i have restored about 3/4s of bothe systems , but need these to finish or finish quicker and with less stress and torment . Any info would be verry much appreciated , please and thankyou

I can relate to the air braking system build as I am restoring an F88 which had it's air tanks moved in the past. Even with full manual and spares books I am stumped when it comes to putting the tanks back as original as the layout in the books is universal. In the circumstances I will go by the knee bone conects to the shin bone type diagram and make my own layout. There are very few N series manuals about so you might have to start from first principles, but decide if you are going Euro or Yank and stick to one or other as there are differences and thats probably where your current mess has derived from. Maybe the best way is to get friendly with another N12 owner and park the two trucks side by side and copy from the good one.
The situation with the wiring is worse as there is more wiring in the cab than on the chassis and you will have a mismatch between two generations of design.
Good luck with it.

Got an 88 or 89 local if a few pics will help Mammoth?
Looks pretty original from a distance.

Thanks Bruce but the UK type F88 has tanks in different arrangement and a heap more relay and other valves. I have an Aussie built 88 as well which will be part of my reference.
Johny hasn't said where he is. ????

Thanks for the reply Mammoth , good idea i just have to find one . From what ive been told and read its an assie model , the chassis is a 12v with 24v start and the cab is 24v system , with the 24v system being at least 3/4s complete , but the 12v system is only about 1/4 complete . Also i think that the pneumatics is incomplete, but only a few pieces . but i keep getting told that every thing is there and every thing worked before the cab change . Thats why im after the N/NL series manuals and diagrams or a vehicel to look at . I have down loaded a huge amount of info on brake systems and components , cataloges and manuals . I havnt put any order to it yet , but if theres anything i can help with just ask , ill do my best to put something together

If only the chassis is the 12/24volt series parralell system then there won't be much on it that will need to be changed to convert to full 24 volt system to suit the later cab. All of the engine sensors should be able to stand the higher voltage, of course the alternator will need to be changed from12volt and starter will already be 24 volt.

Just need to remove the series parralell switch on the battery leads. The cab will have all the 24 volt circuit boards, if you can find out which chassis it came off would help locate the wiring diagram for that one, should be able to get a circuit diagram for it still.

The air side of the early chassis has only a few differences to an american buckjumper. The main one would be that there will be a 4 or earlier 3 way valve located on the outlet of the wet airtank. That and a shuttle valve between the service brake and maxibrake lines on the rear.

Thanks for the reply Mercskeepmeinajob. Your right about the electrics and thats the way im going. Its just that when i started the whole electrics from bothe systems were allready totally disasembled, cut into many pieces and unpluged and removed from the truck and put into a couple of boxes . There are some switchs missing and i think cable harness sections also . Ive just got a copy of a complete F10, F12, F16 LHD electrical service manual of the same era and alot of the parts are the same and some of the circuits seem the same , i hope it helps . Thanks for th reference to the brake system ill look it up and see how i go