this is brilliant work and will come in very handy on reassembly of my car, many thanks for your efforts!
I personally prefer the diagram as is, with the coloured lines.
Agree on keeping the coloured lines. I think it makes it far easier to follow a single wire.
Would it be possible to get a scan of the factory Spider diagram from you? I have the 6-fuse Sprint & Berlina diagrams but not the Spider.
I do not have that diagram either. I researched the pictures on the Giulietta website to determine the components and then wired accordingly based off of the same diagrams you have.
Tony, yes I plan to do the veloce as well. I do not know however to which fuse location the fuel pump should go. It would be great if you could determine that - if not I will take a guess based on current loading.
On advice from others on this list, I replaced the 6 fuse wiring loom in my '57 750D with the later model 8 fuse wiring loom largely because the original fusebox and wiring loom were toast and also because I couldn't find a wiring diagram for the 6 fuse loom. Had I this diagram I may have persisted with the original setup, though I'm told that the 8 fuse system is safer.
Either way, thanks for your hard work Doug - the diagrams look great.
Doug
A very crisp but necessarily cluttered diagram with superb detail.
As you asked for reviews ..
You provide a note stating: no wire indicates chassis connection is made through mounting hardware. This is too general a disclaimer as many of the electrical components must be insulated from earth/ground.
A detailed wiring diagram must indicate how the components needing an earth/ground connection get that ground.
You do not identify the LUCAS thermal switch/circuit breaker in the windscreen wiper circuit as such .. and in the 750D diagram you show both power and (dash switch supplied) earth/ground running though the circuit breaker.
You also do not indicate that this thermal switch/circuit breaker uses bullet connections.
You do not identify the individual thermal sending units for water and oil temps - and the 20 Ohm resistor in the oil temp circuit is not shown.
Some reference to explain that the Grey Tube represents the steering column may be of benefit.
I did all of the changes you suggested but the resistor in the oil sender. My 1955 wiring diagram for the 750's does not show a resistor - my later diagrams do though. If the resistor should be present in the six fuse cars, then I will certainly add that - It would be nice to get a sketch or picture of one so I can make the resistor look realistic.
On the number descriptions, I had used exactly what was printed in the 55 diagram. I did add new descriptions for the items you mentioned and I colored those numbers blue to differentiate them from the originals.
Question: Does the early spider have one horn or two?
My 58 spider veloce arrived without any wiring installed at all, so I'm not going to be able to help with the fuel pump wiring info, I'm afraid. Maybe another BB member could help out?
I think this 6v8 fuse subject has been covered before. As I see it the only difference in the two systems is confined to the right side of the fuse panel where left and right headlights are consolidated to one fuse for both sides, dipped and high beam on the 6 fuse system. This accounts for one less fuse for dipped and high beams. It would seem everything else is the same unless I have over simplified it.
The fuel pump is powered through the ignition switch so there isn't anything magical about that in my opinion and nothing changes..
The resistor is used for the oil temperature gauge. The resistor in an original 1958 Spider Veloce is 20 ohms. I am going to look at the resistor in my 1961 Sprint Veloce, but the oil temperature gauge has never worked to my knowledge.
Doug
Again, with a mind toward clearer understanding.
750B - I have reservations about labeling this diagram as 750B as it is for a very early Sprint with a mechanically activated starter and single horn.
In my mind, a 750B Sprint utilizes a solenoid for starting and requires three wires at the starter motor.
Corrections
You used #14 for the engine to chassis ground strap
and again for electric horn.
(Yes - on very early Sprints there was one horn)
#17 Electromagnetic change-over switch for trafficators - this was copied from an original wiring diagram and is a mis-labeled component.
It is a relay which is activated by the steering wheel mounted ring/button for flashing the headlights.
There remains some serious modification required to get your wiring diagram to agree with the actual connections on a VEGLIA Tri-gauge.
I will address this in a separate message.
Suggestions
#22 - re-position with more space between it and the RIGHT tail light.
Reduce the size of IPRA heater for more space between it and black wire going to #17.
Possibly relocate to lower right area on diagram to better indicate position in right front wing.
Numbers 20,31,32 could be a different color for better identity as gauges housings and not wiring components.
#20 - might be better identified as Tri-gauge with meters or indicators for water & oil temp and petrol level.
#31 Speedometer with dynamo/generator light (not identified).
#32 Revolution counter with oil (pressure) gauge.
Your use of the RED STAR is very effective.
It should be used to indicate the metal housing of the gauges must be grounded.
The wiring connections on this Tri-gauge are somewhat different from present day wiring patterns. This information has been previously discussed on the AlfaBB.
I will use Doug's wiring colors and terminology to now describe what the actual connections are.
First - there are four lamp sockets on the back of the Tri-gauge housing. Three are bonded to the housing (which is grounded/earthed) to the chassis. One additional lamp socket is insulated from the housing - this is the "low petrol level" lamp location. This socket is inter-connected with the three screw terminals that are powered by the Brown wire which comes from terminal 15 on the (#7) ignition/key switch.
Also connected here is the Pink wire from the Dynamo/Generator lamp at the Speedometer.
The end tip of the low petrol level lamp connects to the White wire coming from the petrol level sender.
When viewing the back side of the Tri-gauge the low petrol level lamp is at 8 o'clock.
The directional/trafficator lamp is located at 12 o'clock. The lamp tip is powered by the green wire from terminal L on the automatic blinking device (#18).
At 1 o'clock is the screw terminal for the Oil Temp (it is one of the inter-connected points).
At 3 o'clock is the screw terminal for White/Black wire from Oil Temp bulb (#40).
At 4 o'clock is the lamp socket for Lights. This lamp's tip is connected to a White wire which leads to the fuse block. As drawn, this would illuminate when parking lights are on.
At 5 o'clock is the screw terminal for the petrol gauge (it is one of the inter-connected points).
At 7 o'clock is the screw terminal for Petrol/Fuel Level. The Red wire from the petrol level sender (#22) connects here.
At 8 o'clock is the aforementioned low petrol level lamp socket.
At 9 o'clock is the screw terminal for the Water Temp (it is one of the inter-connected points).
At 11 o'clock is the screw terminal for Yellow/Black wire from Water Temp bulb (#39).
One lamp socket in the center of the Tri-gauge is for illumination. Its lamp tip connects with a wire coming from Instrument Panel light switch (#8) and in common with the other gauges.
Again all great input and thanks for taking the time GTD!
I believe I implemented all of the changes correctly - it took a fair amount of time on the gauge so I hope I got that correct.
I changed the title and added 6 fuse to the name - I already have 8 fuse 750 and 101 diagrams though I will need to update those with the changes we implemented here.
Some of my assumptions which may be wrong on 6 fuse cars
Berlina and Sprint Normale cars used manual engagement for the starter motor
Veloce cars had starter with solenoid
Sprint Normale dash switch order went from L to R - wiper, dash lights, interior lamp
Sprint Veloce dash switch order went from L to R - interior lamp, dash lights, wiper
Sprint Veloce had horn relay and two horns, negative ground and fuel pump, Magneti electrics
I am almost done with the Veloce versions and i will post those soon.
One more point .. all Alfas with Nord engines use clockwise distributor rotation with a 1-3-4-2 firing order.
#1 cylinder wire position on the distributor cap is typically at 2 or 3 o'clock.
Also - just nit-picking here .. if you Zoom in on the LUCAS thermal cut-out (#38) .. the detailed printing is inverted !
Regarding 750D Spider diagram, while I understand that the factory diagrams you are referencing include it ... on a USA market Spider with "football" LUCAS 523 tail lights there were no reversing lamps included in the tail light assemblies.
Just a small note to thank you for your work! I was referred here by Papajam and I am delighted to find the diagram I need to check my Sprint normale's wiring harness. Invaluable help!
Are you still working on the 6 fuse diagrams?
Couple of thoughts (looking at 750E):
I would assume that all 6-fuse setups were tunnel case gearboxes ....... never seen a tunnel case with backup lamp switch.
You show a steering column headlight high/low switch, so the diagram should be marked "not USA", which had the LUCAS floor switch.
I don't see a "door button switch" for the ceiling lamps ......... which is my reason I was interest in the diagram .......... what is left of my 750E harness indicates that the positive (+) wire went to and from the door button instead of a "ground" wire like on all 101 cars. Still trying to find somebody else with the same to verify.
Carl Davis
The early column shift tunnel case cars had backup lights, the switch was mounted forward of the gear changing mechanism attached to the steering gear column in the engine compartment.
If this looks like a duplcate it maybe im not soloed on the bb I need spider v.82 r15 dia.&the fuse box detail TKS for your help.
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