how is battery / starter / fuses / alt wired ?!!?
Discussion
Just planning on replacing the batter cables as i want to relocate my battery.
Had a read of some threads but couldn't quite follow them - it seems that the negative off the car battery goes straight to earth?!?
And the positive terminal has cables to - the fuse box, the starter motor and then alternator. So how is there a "circuit"?!?!
On the 306 forum it would appear you have:
2 no. cables to fuse box from the positive terminal
1 no. cable to the starter motor from the positive terminal
1 no. cable to the alternator from the positive terminal
and then i presume the negave is just earthed off the chassis?!?!?!
any help would be greatly appreciated.
dan
Had a read of some threads but couldn't quite follow them - it seems that the negative off the car battery goes straight to earth?!?
And the positive terminal has cables to - the fuse box, the starter motor and then alternator. So how is there a "circuit"?!?!
On the 306 forum it would appear you have:
2 no. cables to fuse box from the positive terminal
1 no. cable to the starter motor from the positive terminal
1 no. cable to the alternator from the positive terminal
and then i presume the negave is just earthed off the chassis?!?!?!
any help would be greatly appreciated.
dan
torqueofthedevil said:
Just planning on replacing the batter cables as i want to relocate my battery.
Had a read of some threads but couldn't quite follow them - it seems that the negative off the car battery goes straight to earth?!?
And the positive terminal has cables to - the fuse box, the starter motor and then alternator. So how is there a "circuit"?!?!
On the 306 forum it would appear you have:
2 no. cables to fuse box from the positive terminal
1 no. cable to the starter motor from the positive terminal
1 no. cable to the alternator from the positive terminal
and then i presume the negave is just earthed off the chassis?!?!?!
any help would be greatly appreciated.
dan
HiHad a read of some threads but couldn't quite follow them - it seems that the negative off the car battery goes straight to earth?!?
And the positive terminal has cables to - the fuse box, the starter motor and then alternator. So how is there a "circuit"?!?!
On the 306 forum it would appear you have:
2 no. cables to fuse box from the positive terminal
1 no. cable to the starter motor from the positive terminal
1 no. cable to the alternator from the positive terminal
and then i presume the negave is just earthed off the chassis?!?!?!
any help would be greatly appreciated.
dan
I don't mean to be rude, but buy yourself a haynes manual for the 306 and have a look at the wiring diagram. If that doesn't help, please, for your own safety, take the car to an auto-electrician to carry out the work so you don't lose your P+J to a big, firey inferno
FYI, the circuit for the starter will go approximately:
Battery ---> Fuse box ---> Ignition barrel ---> Starter motor ---> Earth
The circuit is open because the ignition is not switched to position 2. When you turn the barrel (past the first click (1), and on to the 2 (the spring loaded section)), the circuit is made and the starter motor will fire.
The alternator is driven from the engine by a belt. There are magnets, coils and diodes which induce current and rectify it before it hits the battery, in order to trickle charge it whilst the engine is running.
Wing Commander said:
torqueofthedevil said:
Just planning on replacing the batter cables as i want to relocate my battery.
Had a read of some threads but couldn't quite follow them - it seems that the negative off the car battery goes straight to earth?!?
And the positive terminal has cables to - the fuse box, the starter motor and then alternator. So how is there a "circuit"?!?!
On the 306 forum it would appear you have:
2 no. cables to fuse box from the positive terminal
1 no. cable to the starter motor from the positive terminal
1 no. cable to the alternator from the positive terminal
and then i presume the negave is just earthed off the chassis?!?!?!
any help would be greatly appreciated.
dan
HiHad a read of some threads but couldn't quite follow them - it seems that the negative off the car battery goes straight to earth?!?
And the positive terminal has cables to - the fuse box, the starter motor and then alternator. So how is there a "circuit"?!?!
On the 306 forum it would appear you have:
2 no. cables to fuse box from the positive terminal
1 no. cable to the starter motor from the positive terminal
1 no. cable to the alternator from the positive terminal
and then i presume the negave is just earthed off the chassis?!?!?!
any help would be greatly appreciated.
dan
I don't mean to be rude, but buy yourself a haynes manual for the 306 and have a look at the wiring diagram. If that doesn't help, please, for your own safety, take the car to an auto-electrician to carry out the work so you don't lose your P+J to a big, firey inferno
FYI, the circuit for the starter will go approximately:
Battery ---> Fuse box ---> Ignition barrel ---> Starter motor ---> Earth *
The circuit is open because the ignition is not switched to position 2. When you turn the barrel (past the first click (1), and on to the 2 (the spring loaded section)), the circuit is made and the starter motor will fire.
The alternator is driven from the engine by a belt. There are magnets, coils and diodes which induce current and rectify it before it hits the battery, in order to trickle charge it whilst the engine is running.
But if you need to ask you really do want to get the job done by an electrician.
I hesitate to ask but...
why do you want to move the battery?
It isn't in such a bad place if I remember it well
Whatever you end up doing make sure you can strap it down to prevent its innards shaking themselves apart.
hi, thanks for your help. no offense taken. I relaise i dont sound like i know what i'm doing (I don't!) and i do plan to get a haynes manual.
I dont want to move the battery far - i have a racing battery though which is a bit smaller and just wanted to move it back a bit and the cables are already on the limit (i.e. no movement in them)
I had a look at a thread on an owners forum and it had a guide where somebody had moved the battery to the rear of the car (to help with weight distribution) and they had bought a kit that simply replaced the cables i mentioned. i.e.
a cable from the negative stright to the chassis
then two cables from positive to fuse box
one from positive to alternator
one from positive to starter motor
obviously there would be other cables running about from fusebox to barrell etc. but that was what he changed to allow the battery to be moved?!?!?!
what does that sound like?!?!?
I dont want to move the battery far - i have a racing battery though which is a bit smaller and just wanted to move it back a bit and the cables are already on the limit (i.e. no movement in them)
I had a look at a thread on an owners forum and it had a guide where somebody had moved the battery to the rear of the car (to help with weight distribution) and they had bought a kit that simply replaced the cables i mentioned. i.e.
a cable from the negative stright to the chassis
then two cables from positive to fuse box
one from positive to alternator
one from positive to starter motor
obviously there would be other cables running about from fusebox to barrell etc. but that was what he changed to allow the battery to be moved?!?!?!
what does that sound like?!?!?
hi, thanks for your help. no offense taken. I relaise i dont sound like i know what i'm doing (I don't!) and i do plan to get a haynes manual.
I dont want to move the battery far - i have a racing battery though which is a bit smaller and just wanted to move it back a bit and the cables are already on the limit (i.e. no movement in them)
I had a look at a thread on an owners forum and it had a guide where somebody had moved the battery to the rear of the car (to help with weight distribution) and they had bought a kit that simply replaced the cables i mentioned. i.e.
a cable from the negative stright to the chassis
then two cables from positive to fuse box
one from positive to alternator
one from positive to starter motor
obviously there would be other cables running about from fusebox to barrell etc. but that was what he changed to allow the battery to be moved?!?!?!
what does that sound like?!?!?
I dont want to move the battery far - i have a racing battery though which is a bit smaller and just wanted to move it back a bit and the cables are already on the limit (i.e. no movement in them)
I had a look at a thread on an owners forum and it had a guide where somebody had moved the battery to the rear of the car (to help with weight distribution) and they had bought a kit that simply replaced the cables i mentioned. i.e.
a cable from the negative stright to the chassis
then two cables from positive to fuse box
one from positive to alternator
one from positive to starter motor
obviously there would be other cables running about from fusebox to barrell etc. but that was what he changed to allow the battery to be moved?!?!?!
what does that sound like?!?!?
torqueofthedevil said:
I had a look at a thread on an owners forum and it had a guide where somebody had moved the battery to the rear of the car (to help with weight distribution) and they had bought a kit that simply replaced the cables i mentioned. i.e.
a cable from the negative stright to the chassis
then two cables from positive to fuse box
one from positive to alternator
one from positive to starter motor
obviously there would be other cables running about from fusebox to barrell etc. but that was what he changed to allow the battery to be moved?!?!?!
what does that sound like?!?!?
That sounds spot on.a cable from the negative stright to the chassis
then two cables from positive to fuse box
one from positive to alternator
one from positive to starter motor
obviously there would be other cables running about from fusebox to barrell etc. but that was what he changed to allow the battery to be moved?!?!?!
what does that sound like?!?!?
Pigeon said:
torqueofthedevil said:
I had a look at a thread on an owners forum and it had a guide where somebody had moved the battery to the rear of the car (to help with weight distribution) and they had bought a kit that simply replaced the cables i mentioned. i.e.
a cable from the negative stright to the chassis
then two cables from positive to fuse box
one from positive to alternator
one from positive to starter motor
obviously there would be other cables running about from fusebox to barrell etc. but that was what he changed to allow the battery to be moved?!?!?!
what does that sound like?!?!?
That sounds spot on.a cable from the negative stright to the chassis
then two cables from positive to fuse box
one from positive to alternator
one from positive to starter motor
obviously there would be other cables running about from fusebox to barrell etc. but that was what he changed to allow the battery to be moved?!?!?!
what does that sound like?!?!?
most cars the feed from the alternator runs to the large terminal on the starter solenoid (the smaller of the two parts that make up the starter) and so does the feed to the rest of the car's electrics, so feeding the battery lead to there ensures the power to recharge gets back into the battery.
So you would probably find that the one from battery live to the starter is a thick one (to enable the high power current to drive the starter) and the other from the alternator to the same terminal will be thinner as it is simply a charging supply. (thicker than a wire to any lamp but not as thick as the stater wire)
I hope I haven't over complicated this but if you have to start learning somewhere PH is a good place to start
yeah thats sound.
as i will only be replacing:
positive to starter
positive to alt
positives to fusebox
negative to earth
I was just going to use 20mm2 cable for them all? its rated at 120A and cranking ampage is only 95 i think, so would that be ok?
Also, can you just confirm that the negative terminal on the battery simply goes straight to earth?!?!? Seems bizarre that there is not a "circuit" back to the battery! it contradicts everything i've ever been taught about electricity!
as i will only be replacing:
positive to starter
positive to alt
positives to fusebox
negative to earth
I was just going to use 20mm2 cable for them all? its rated at 120A and cranking ampage is only 95 i think, so would that be ok?
Also, can you just confirm that the negative terminal on the battery simply goes straight to earth?!?!? Seems bizarre that there is not a "circuit" back to the battery! it contradicts everything i've ever been taught about electricity!
There will be an earth cable from the body/chassis to the engine somewhere, usually down deep and dirty and often subject to rust and other forms of vile corruption.
THIS cable will complete the circuit your head tells you is ALL WRONG!
circuit runs:
batt plus-
starter solenoid-
wiring loom-
cars electrics-engine electrics-separate sets of stuff
body-
batt neg/earth
battery itself
So it's all in the invisible earth strap down below... or behind a plastic filter box or underneath a battery mounting platform "If I Remember The Pug 306s I used to work on"
But whichever car, it is there somewhere
THIS cable will complete the circuit your head tells you is ALL WRONG!
circuit runs:
batt plus-
starter solenoid-
wiring loom-
cars electrics-engine electrics-separate sets of stuff
body-
batt neg/earth
battery itself
So it's all in the invisible earth strap down below... or behind a plastic filter box or underneath a battery mounting platform "If I Remember The Pug 306s I used to work on"
But whichever car, it is there somewhere
To give you a bit of perspective, which I think always helps, I once took a look at a Group A car prepared by Andy Rouse to get an idea of what they did regarding battery placement. It didn't take long - it was in the standard position.
I think a lot of people put a lot of effort into making changes that in reality won't make that much difference, and if I were in the OP's position I would keep the battery in the OE position. That also happens to be the very best place for it if the vehicle is in an extremely destructive accident.
I think a lot of people put a lot of effort into making changes that in reality won't make that much difference, and if I were in the OP's position I would keep the battery in the OE position. That also happens to be the very best place for it if the vehicle is in an extremely destructive accident.
i know what you are saying about minor changes but if people are competing you do what every you can! I am not actually relocating to the boot, i just need a few inch as i have a small battery and just want to shift it back towards the bulkhead.
Also, i just enjoy replacing / upgrading things so would be nice for the cables to have a bit of an overhaul.
Cheers
Also, i just enjoy replacing / upgrading things so would be nice for the cables to have a bit of an overhaul.
Cheers
Gassing Station | Engines & Drivetrain | Top of Page | What's New | My Stuff


