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Two wiring questions

Featured Replies

Hi, EA82T

 

1) Does anyone know if the coil bracket itself needs to be earthed? i.e. do the bolts holding the brackets need to connect to the metal of the body?

 

2) Can anyone tell me what to connect the alternator up to:

 

-doing a lot of wiring from scratch and I cant work out what the two spade wires on the back of the alt are for -I'm assuming one is Ign switched +'ve and one ??warning light but cant tell which is which!

 

Does the alt ground through the body or does the screw hole marked with the Earth symbol actually need wiring to -'Ve? Assuming also that the big connector marked BAT is the main direct to batery +'Ve connection. Am I missing anything?

 

 

thanks a million for any help. :banana:

1) yes, the coil bracket MUST have a good earth/ground

2) can't recall for small wires, but know large wire goes through fusible link to battery + ; there are no relays involved

the alt grounds through the body - you should have a full-sized battery cable running in near the starter from the - side of the battery - this is supposed to ground the engine and transmission, but another, smaller ground wire to the engine is also a good idea

  • Author
1) yes, the coil bracket MUST have a good earth/ground

2) can't recall for small wires, but know large wire goes through fusible link to battery + ; there are no relays involved

the alt grounds through the body - you should have a full-sized battery cable running in near the starter from the - side of the battery - this is supposed to ground the engine and transmission, but another, smaller ground wire to the engine is also a good idea

 

thanks, gets me started with the big stuff

 

any idea what size fuse for the alt-battery lead?

 

Anyone else tell me what the two spade connectors are for? (they are arranged perpendicular to each other in a single connector type thing)

OK, I looked it all up:

the fusible link is rated for ~21 Amps because the wire diameter is 1.25 square mm and the fsm specs that as the max allowable current for the wire - run a LARGE gauge wire for this lead!! the stock wire is rated for 51A!!- note: fusible link not fuse - fusible link is a small, sacrificial piece of wire, not a bus or cartridge fuse - fuses behave very differently than fusible links

 

the white/red stripe wire at the base of the T on the small connector goes to dash warning lights - it should be a smaller wire

 

the black/white stripe wire at the top of the "T" on the small connector goes to the battery as well, through a .85 square mm fusible link (~16A) hope that gets you somwhere!!

  • Author
OK, I looked it all up:

the fusible link is rated for ~21 Amps because the wire diameter is 1.25 square mm and the fsm specs that as the max allowable current for the wire - run a LARGE gauge wire for this lead!! the stock wire is rated for 51A!!- note: fusible link not fuse - fusible link is a small, sacrificial piece of wire, not a bus or cartridge fuse - fuses behave very differently than fusible links

 

the white/red stripe wire at the base of the T on the small connector goes to dash warning lights - it should be a smaller wire

 

the black/white stripe wire at the top of the "T" on the small connector goes to the battery as well, through a .85 square mm fusible link (~16A) hope that gets you somwhere!!

So to make a fusable link I just connect a piece of the right size wire in serries with the main cable - cool. I think!

 

Then for the "T" shape spades, the down piece (marked L on the alt) (I dont have wires to confirm) goes to dash light

 

top of "T" (marked S) again no wire to confirm color, goes to battery ??via ignition switch?

 

thanks again I think I'm getting the picture and will be able to put it together with this info if I've understood it properly.:clap:

So to make a fusable link I just connect a piece of the right size wire in serries with the main cable - cool. I think!

sorry, but it isn't that easy - they are specifically designed to fail at a particular point, normal wires usually have some overhead, which could cause a dangerous overload situation - if you can reuse the ones from the orig. harness, you should be set; otherwise, you will need to buy them from an auto parts store - most any should have them because virtually all cars I have seen have some sort of fusible link protecting the alternator - you shouldn't have trouble finding them, and generics should work fine

 

I will have to check the body on my alt. later for the correct markings - I have physics class in a few minutes, and I got to go to that now!

 

Cheers!

  • Author
sorry, but it isn't that easy - they are specifically designed to fail at a particular point, normal wires usually have some overhead, which could cause a dangerous overload situation - if you can reuse the ones from the orig. harness, you should be set; otherwise, you will need to buy them from an auto parts store - most any should have them because virtually all cars I have seen have some sort of fusible link protecting the alternator - you shouldn't have trouble finding them, and generics should work fine

 

I will have to check the body on my alt. later for the correct markings - I have physics class in a few minutes, and I got to go to that now!

 

Cheers!

 

thanks again, I'll get the right stuff for the protective link from a wiring place. :)

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