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TR2/3/3A Generator Light

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M_Pied_Lourd

M_Pied_Lourd

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Hi guys,

Let me first say, wiring is NOT my strongest suit :cool:

Need some help as to where I should be looking first.

The background. Car has been converted to negative ground. Car has had an alternator conversion. It has a gutted/shunted control box with the stock wiring harness attached.

When the car is running, the generator light is glowing bright red. It doesn't go out even when the revs go up. The needle on the amp meter stays in the middle. It does swing slightly if I turn on a signal light etc or turn on the wipers.

So, where to start?

Any help would be appreciated.

Cheers
Tush
 
Sounds like the alternator may not be charging. Start by making sure that the belt is not slipping, and no wires have come loose anywhere. Then hook up a voltmeter to the battery without the engine running and note what the reading is. A fully charged battery will be about 12.5 volts. Even if it's lower and starts the car, that's OK. Start the engine, run about 1500 rpm. The voltage should swing up to about 13.7-14.2 volts. If there is no, or very little increase, then the alternator is not charging. Why may require some more investigation and checks, but first a couple of questions.

...Does the charge light come on when you turn on the ignition BEFORE you start the car?? It should. Which alternator do you have in there?? Delco 10SI? Hitachi? Lucas? That will help with the diagnosis.
 
Hi Art,

First, thanks very much for the reply.

I'll answer what I can tonight and I'll do the run up test tomorrow morning.

Gen light is on before I push the ignition button. I believe I have the Delco 10si. The belt is not slipping. Battery is brand new and was reading 12.4 this afternoon before I installed it.

Cheers
Tush
 
Hi Tush

Agree good to check voltage with car running to eliminate non-charging alternator. Here is how my wires are run with alternator conversion. Note that the wire for light is moved from D to F terminal. Email me if you need more information. Have lots of documentation on conversion.

Cheers, Mike

Mod Control Box.jpg
 
Thanks Mike!

Cheers
Tush
 
Ok, after a test, it looks like I am in a non charging condition. Voltage does not rise from about 12.3 V during revving of the engine.

Where to next?

Looks like I have two wires coming off the stock harness that lead to the alternator conversion. There is a white push in connector on the alternator along with a single pin/lock nut.

Cheers
Tush
 
Are you getting 12 v supplied to the smaller wires.

Alternaor.jpg

This is the instructions that came with my alternator. Red wire on the plug gets 12 v all the time and the white wire is switched at the ignition switch.

The pin and lock nut may be the ground for the alternator.

David
 
Thanks All

Please read my first post....I'm a dumb ass!

Ok, so I dug out the wiring schematics that came with the conversion. I must have had some sort of brain fart when I was hooking up the connections. I connected the alternator end correctly...not so much the control box end. I think it would have been perfect for a stock generator though:wink-new:

I swapped wires around and now the red light is off and I'm showing a slight discharge on the amp meter. When I rev the engine, it is showing that it is charging as I'm getting + 13 V revving from idle.

I still have one question though...

I have one black wire for the control box...instruction tell me that I should have two? It tells me to tie together the two and retain a ground connection. So, just wondering why my harness has only one black? Regardless, I have put it to ground on the firewall attached to where the other main harness ground is next to the battery box.

Now, although I'm short one black wire, I seem to have on extra small brown wire (no tracer). Not sure where this should go? I put it on a small push on connector on the control box below my large brown/white and large brown/blue. Hope that's correct?

Cheers
Tush
 
(quote)I have one black wire for the control box...instruction tell me that I should have two? It tells me to tie together the two and retain a ground connection. So, just wondering why my harness has only one black? Regardless, I have put it to ground on the firewall attached to where the other main harness ground is next to the battery box.

Now, although I'm short one black wire, I seem to have on extra small brown wire (no tracer). Not sure where this should go? I put it on a small push on connector on the control box below my large brown/white and large brown/blue. Hope that's correct? (enquote)

Should only be one black wire coming out of the loom. (comes from the facia) The 2nd black wire is only from the control box to a spot on the scuttle right there at the box. It's probably OK not to have that short wire, but Triumph was famous for not having good grounds. I would remedy that missing short wire. (If you have ever had fuel gauge problems in the past, that missing short wire may have contributed to the cause.)

If you have an overdrive, the small ga brown wire is probably the the wire to the C1 connector on the OD relay. It would come off the A connector on the control box. The schematics for the overdrive wiring sub-harness' vary from provider to provider. Some say the wire should be brown & come off the A1 connector on the fuse box. Others say it should be brown w/white tracer & come off the A connector on the control box. Either one is acceptable. Your location is fine.
Frank
 
Thanks Frank. I appreciate it.

Cheers
Tush
 
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