1jzgte alternator overcharging, changed regs...still doin it?

[cambelt]

The corona mk 2 sense wiring runs thru the car wiring which will have a fair drop in it , Wire the sense terminal to the main B+ on the alt and see what it does .
On many conversions ive seen this is the way its been connected while technicaly not correct it works ok.
The mark 2 sense wire connects at the alt B+ ring terminal and runs thru the loom to the 6 pin black REG plug (and back to the alt if yr using the 3 original mark 2 alt reg wires for a JZ alt).
If you want to use the mark 2 wiring you have to have the original mark 2 alt B+ connected to yr Main battery + post via a 40 A fusible link to prevent any voltage drop OR link it too the cars original main + feed ( orig near the battery) and then thru a 60 A fusible link .
Dave

[IN 05 NT]

that kinda explains a bit cambelt!,

the water pump issue seems to be sorted now, with davies craig saying that they have updated the water pump controller fuse to a 15amp, rather then the 10amp fuse it came with, (didnt play up at all for a 1/2hr lunch break drive)

BUT, the ignition fusible link has just blown for the 2nd time, so might have a go at wiring it up as per cam's direction's and see how that goes.

edit: heres a pic of how its running, the green plug im holding is what the fusible link plugs into, which is just connected to the distribution block.....the black wire is the alternator charge wire....

[stidnam]

for what its worth I hate electricity

[allencr]

Optimistic gauge/meter/whatever????
Is the battery giving off lots of fumes, electrolyte bubbling/boiling or getting hot to the touch? If not, it's close enough to spec & I'd leave it alone.
Would you have cared at all about the voltage if it wasn't for the ISSUE thing.

the water pump issue

[IN 05 NT]

haha, the water pump isnt the problem now......thats seems to be sorted,

its now just blowing the fusible linki once i get up it,

ive got 2 alternators to try now, thanks to seamonsta and linden,

so will see the charge rate after the swap............

oh we used 2 different testers.....so the voltage is 14.7........

[oldcorollas]

fusible link blowing = too much current being drawn by something.
you have other issues perhaps.

[stidnam]

As Blake said it seems to be blowing after a state of high revving for a few moments

The way its been wired is that EFI, fuel pumps, water pump, Injectors, aftermarket gauges and thermo fan are all on their own relays drawing power from that junction thing in the engine bay.

The only things left that would be drawing power on the circuit thats blowing the fusible link would be all the original electrics in the car being lights, dash gauges, stereo, ignition etc

The only thing connecting the body loom back to the motor loom are two spliced wires into the ingition wires. Both wires run through 7.5amp fuses before they get to the ecu and aren't being used to power anything other than activating a few of the aforementioned relays. Could any of those relays running off the ignition circuit cause the link to blow?

stidnam

[IN 05 NT]

just swapped over one of the alts and the charge rate is the same?.....im just going to leave it at that.......assume its fine.......as its within specs.......

but its interesting to know that when i turn the interior blower fan on it spikes from 14.65 to 14.8.... when turning headlights/thermo fan/ any other accessory on and it doesnt effect it?

[oldcorollas]

how is the interior blower earthed?

if the voltage passing through the blower raises the relative groudn that the sense wire is seeing, then the alt will increase voltage.

ie if the ground for the blower is not good enough...

do you just have the battery in the boot connected to the floor? or to a dedicated cable?

got long enough jumper leads to run from neg terminal of battery, to the engine block, and to the alt housing?

edit: where's cool1 when you need him...

edit2: have you tried measuring voltage when the car is not running?
ie, measure across battery posts..
then measure from sense wire to engine block and alternator body and the chassis...

[Cuzzo]

Yes are you running a neg cable to the motor also?
or to the chassis rail?

[IN 05 NT]

ive got 2 earths in the boot, (on clean metal-metal surface) and one small earth strap on the head, one on the block, one on the bellhousing, and one on the gearbox.....

all body contacts were taken back to metal....then paint over once the earth was bolted back on...

["Z" UTE]

Blake, how old is the battery?, it sounds like when you try to draw some extra amperage from the battery, the battery is dropping off quicker than it should, and the alternator is responding by throwing out a bit more juice.

cheers Chuck.

[turbo ke20]

ok just to clear things up.

toyota nippon denso alternators have a high charge rate. Its normal to see 14.7 volts coming out of them.

the reason you are still seeing 14+ volts across your battery when it is off is beacuse of the surface charge.

once you either crank the engine over a few times or load tes the battery it will drop down to the normal battery voltage.

Nothing to worry about.

With the fusible link blowing.......what amperage is the link??

put an ammeter in series with the wire and check the current draw (your multimeter only might have a max of 10A) so best to use a analogue meter with a high scale on it.

Or if you can trace exactly what runs off the link try disconnect each auxillery one by one till it dosent blow.

hope this helps you out a bit

justin

[IN 05 NT]

surface charge of the battery isnt an issue, it drops down to 12. something once it was turned off,

the fusible link is 23A......

we have a feeling the problem has been solved now, due to a LIVE wire that was taped up, then untaped, and left that way, earthing on the body...since that has been taped up again, it hasnt blown the fuse at high revs, or any other driving conditions for nearly a week now.........

though im still carrying a spare link just incase ,

cheers, Blake

[The Witzl]

Blake,

Thanks for posting up pics of that distribution post. I'm going to add that to the Jaycar range now