Just to answer your questions:
1. In your first pic you say "How it should be and how it was". Can you see the text in purple? It says Model 12si Delco. You said you have 10si. Whick is kind of true. Maybe you already knew the old one was a 12si? If it matched your first pic.Our original altenator was a Delco Si-10. I used that picture to show were the stud is supposed to be. Couldn't find a better picture of a Si-10 so used this one. Same location (upperside left when the 2 terminals are pointed to above
2. In your second pic you say "our alternator". That seems to be a 10si. HOWEVER, the big battery terminal is in a different place than normal. You can see that the normal place just looks like a nut in your pic, but next to it says "BAT". I assume it is like that because it was converted to Positive ground but I do not know.That was my also my guess. it is a si-10, but converted.
3. You can test the alternator, with all wires disconnected, to see which it is, positive or negative ground.
Use Multimeter set to ohms/resistance.
Tested the altenator and you can guess it... ITS a POSITIVE!!!
Used your technique (very helpful :D) and noticed that when I put the positive probe (red) on the BAT and the negative (black) on the casing it shows low resistance. Reverse the probes and its high resistance. Now i know that I have the wrong altenator and need to get the other one back!
You said: The chassis is negative grounded to the battery through the "cut off switch". Is this right or not?
Please explain where the battery negative cable goes.
To the cut off switch? Thru the switch to the frame?So the negative cable goes from the battery, through a small hole in the floor and ends up on the cutoff switch which is connected to the dashboard. (see pictures) When we turn the switch to the left the ground is cut of from the battery so it doesn't go flat over night. I know it shouldn't go flat, but first i want to repair the altenator and then search where the battery loses its electricity.
DO NOT use the word "chassis" when speaking about electrical. It is too vague. There is a frame, body sheet metal and the Motor. Normally the negative battery cable goes to the motor. Then there are straps from motor to the frame and from frame to body. It can vary as long as all three are connected. I do not recommend a cut off switch. Especially for a person with problems and a person looking to use a distribution point and eliminate so many connections/resistance points.I will look into that with my dad tomorrow. I do understand that you don't recommoend a cut off switch, but we use one in our MG B for years and never had any problem with it. I know that there is a loose strap inside the battery box which we removed for the cutoff switch, maybe that is connected to the engine!
I recommend you order an alternator from the states. CLICK [amazon.com]
Use the free trial, I do that all the time. CLICK [amazon.com]I will look into that! tommorow morning i will call our friend about the altenator. The old altenator will be rebuild by someone who has a shop for that. So i will wait for the answer for that! Otherwise i will buy it from amazon, luckely the one you send ships to the Netherlands (very uncommon) so that won't be a problem!
I can't thank you enough for the amount of effort you put in it for me and that you are willing to share your knowledge! It helps a lot and without it i would never be able to repair it! I'm understanding more and more about how it all works
