Aaaarrrggghhhh!
Discussion
Hi peeps..Spoke to the garage this morning and they were having problems with fuelling..I have just spent 200 sobs on a purpose built WUR/Pressure reg..That has now been sorted as the pressure has been altered on the metering head side to accomodate and delilah is ticking over smoothly with no stalling..The Amethyst system is mapped and working..But the Brand new race alternator which started off badly as there was no battery light has now decided to give up altogether and they are hand-built and tested which takes 2-3 days..The garage is going to see if a standard capri one will fit for now..what a poxy nuisance...Ziga
Mark the light from the alt is one wire from the field coil.
When the alt is not turning an earth will light the battery backed lamp on the dash.
As the alt starts to turn it will rise to 12v and lamp will go out.
(12v both sides of lamp no current flow lamp will not glow.)
Edit to add.
the other wire is from the key and sends 12v in other direction to the Alt.
It sounds possible (almost likely) that the two wires were reversed.
When the alt is not turning an earth will light the battery backed lamp on the dash.
As the alt starts to turn it will rise to 12v and lamp will go out.
(12v both sides of lamp no current flow lamp will not glow.)
Edit to add.
the other wire is from the key and sends 12v in other direction to the Alt.
It sounds possible (almost likely) that the two wires were reversed.
Edited by jeff m2 on Monday 10th June 18:19
Hi Peeps..The alternator is an 80amp and was supplied by ratsports and is built to order..I was told that every one is tested before it s sent out..The garage was saying something about the wires being the wrong colour?..
The RED is coming from the IG and the GREEN is attached to the L and the BLUE is attached to the S...
The RED is coming from the IG and the GREEN is attached to the L and the BLUE is attached to the S...
You sorta got it right between you
IG ignition
L lamp
S sense Do you need this one? isn't it internally regulated, most are nowadays.
S would go to an external voltage regulator. (or in very modern cars to an ecu)
Big thick guy to the battery.
Ignition on, at the expense of blowing a fuse, briefly ground one of the two wires in your wiring loom, if the charging light flashes on the dash put that wire on L.
Put the remaining wire on IG, that's your excite voltage for the Alt.
Personally I would go back to the garage, they should not have let this out of the shop without the charging light working.
Next time get a Denso, they make quite small ones with decent output.
IG ignition
L lamp
S sense Do you need this one? isn't it internally regulated, most are nowadays.
S would go to an external voltage regulator. (or in very modern cars to an ecu)
Big thick guy to the battery.
Ignition on, at the expense of blowing a fuse, briefly ground one of the two wires in your wiring loom, if the charging light flashes on the dash put that wire on L.
Put the remaining wire on IG, that's your excite voltage for the Alt.
Personally I would go back to the garage, they should not have let this out of the shop without the charging light working.
Next time get a Denso, they make quite small ones with decent output.
Thanks Jeff..The garage did check the battery light/Ignition light and that worked but from day one the lamp current seemed to be non-existent..I should of took it back to the shop..Yep..I think i should of listened to others that recommended a denso alternator a while back!..The shop that supplied the alternator is going to test it again before they can exchange it as they are built by someone else for them and built to order...The garage tested the output when it was running and it was charging ok..Ziga
Get a 3-pin Denso off of a Toyota or Honda.
You need something like this:
http://www.ebay.co.uk/itm/2000-2005-TOYOTA-CELICA-...
Far more efficient than the stock Lucas.
New tails are available on eBay.
Get it checked out, have some new brushes fitted then strip it to get the case vapour blasted like new and the pulley zinc plated.
Job done.
Circa 80A-100A output.
Phil
420 SEAC
You need something like this:
http://www.ebay.co.uk/itm/2000-2005-TOYOTA-CELICA-...
Far more efficient than the stock Lucas.
New tails are available on eBay.
Get it checked out, have some new brushes fitted then strip it to get the case vapour blasted like new and the pulley zinc plated.
Job done.
Circa 80A-100A output.
Phil
420 SEAC
OK. Read this and see if it helps, as this is the way I know it.
When the engine starts up and the alternator pulley starts spinning, the alternator doesn't automatically start charging. For it to start charging, the alternator has to be excited by an incoming power supply. This tells the alternator that the engine has started up and that it should start charging. This power supply for the excitement signal comes from one side of the ignition light bulb, but, for this to occur, the bulb on the dash (ignition light bulb) has to be the correct wattage or the whole system fails. What is that wattage I hear you ask? Well the higher the better, as the alternator then receives the signal quicker, but I believe normally it would be around 2.5 Watts.
This was something I never knew before and I found this out the hard and expensive way on one of the TVR's I had bought a while back.
Tony. TCB.
When the engine starts up and the alternator pulley starts spinning, the alternator doesn't automatically start charging. For it to start charging, the alternator has to be excited by an incoming power supply. This tells the alternator that the engine has started up and that it should start charging. This power supply for the excitement signal comes from one side of the ignition light bulb, but, for this to occur, the bulb on the dash (ignition light bulb) has to be the correct wattage or the whole system fails. What is that wattage I hear you ask? Well the higher the better, as the alternator then receives the signal quicker, but I believe normally it would be around 2.5 Watts.
This was something I never knew before and I found this out the hard and expensive way on one of the TVR's I had bought a while back.
Tony. TCB.
Interesting idea - winding (sic) back from that, the alternator itself works by the regulator creating a magnetic field in the field windings, which are on the spinning armature. If more voltage is needed then the regulator ups the current, and vice versa if less. The stator windings get an alternating voltage induced in them (hence the name alternator) which then is rectified by diodes to give the (reasonably DC) charge voltage.
On some alternators the lamp connector may well affect the operation of the regulator, on others it's just an output. So as Tony says, you need to pay attention to this, I would find out the manufacturer's spec and adjust the bulb fitted, as appropriate.
On some alternators the lamp connector may well affect the operation of the regulator, on others it's just an output. So as Tony says, you need to pay attention to this, I would find out the manufacturer's spec and adjust the bulb fitted, as appropriate.
Rockettvr said:
I'm assuming that you've checked the bulb to make sure it hasn't failed/ been blown ?
Hi mate..They have checked the operation of the ignition light a few times and its worked everytime..I should of took the alternator back the first day as it was tested before the car was started and there was no ignition light..I did phone the shop who supplied it and he seems to think no-one knows how to fit an alternator..All he kept saying was.."The guy that builds them for us does it 8hrs a day 7 days a week so he know what he is doing"..Oh hang on i think we have found someone who NEVER makes a mistake..And the parts he uses are infallible..Total and utter BULL..Zigamrzigazaga said:
So does this mean that i have to remove the dash and change the bulb in order to uprate my alternator?..So the whole supercharger project is hindered by a light bulb?..Thats just outrageous!..Cant i wire a separate bulb in?...Cheers...Ziga
Yes, you can wire a separate new bulb in and try different wattage bulbs to have the desired effect of exciting the alternator on start up. Also, just because the bulb works, or doesn't work makes no difference. It has to be the correct wattage or higher to have the desired effect. Bearing in mind, the new wired bulb has to be wired in the same way as the existing one, where one side goes to the alternator and the other I believe to the ignition.On a TVR I bought a while back I was going out of my mind trying to sort out a similar problem. I took the alternator off and had it tested only to be told that the alternator was charging fine and the diodes were all in good condition. Not even the auto electrician could work it out, as the wiring on the car was checked and found to be correct. It wasn't until the guy who builds alternators in the workshop explained to me how the system works, I realised that the bulb in the dash plays a major role in charging. Though this may nor necessarily be the problem with yours, it is worth investigating. All the best and good luck.
PS. there is a way of testing if the alternator is not being excited by the bulb on start up. Once the car starts you can momentarily short the main live output of the alternator to the input wire that excites on start up, on the alternator with a short piece of wire. Because full wattage is being provided, the alternator should start charging instantly and your amp meter will go up, until you switch the car off, then it's back to square one. Though I don't recommend you do this test unless you know what you're doing, in case you cause damage to your new alternator.
Tony. TCB.
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