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TR6 Fry a TR6 electrical system in these easy steps

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tdskip

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Simply follow the following seven easy steps just like I did this AM....

1) Get up stupid early so you can get a partial day of working on the cars in before the family realizes that you are missing

2) Drive to where the TR6 is stored, preferably several hours away so commercial radio can numb you brain into mush

3) Start your car day by working an early positive earth Sprite

4) Have coffee with the neighbor, but continue thinking about the Sprite

5) Decide it is time to work start the TR6, but continue to thing about the Sprite in the background

6) Install new battery in TR6 backwards while thinking about the Sprite

7) Stand back and enjoy the spark and smoke....

Bugger. Electrical system is totally dead now...
 
Wow sounds like quite a show, Do you do parties Skip?


Sorry to hear of your misfortune, sounds like a good time to replace the wire harnesses
 
Generally speaking, hooking up a battery backwards will only hurt electronic units, like the alternator and radio. ( Perhaps electronic ignition if fitted.)If you switch polarity on a generator equipped car, it is no big deal. So, when the smoke clears, you will likely find things are not as bad as they seem now. Test carefully, and you will be back up in no time.
 
There's at least one other very easy way to "smoke" a TR. It's as simple as trying to remove and replace an indifferently (and very poorly) installed modern stereo, in this case, in a TR250. Fortunately, all I got to see were a few sparks...no Roman candles or M80s or billowing smoke!

And no, I didn't do the original indifferent, poor stereo installation!
 
Thanks for the words of support guys!

I do have an essentially new Petronix which I installed about 100 miles ago...

Any ideas of how to get testing to see just how much damage I did? Where would I start?

Maybe this is the push I needed to get good at wiring - grin.
 
tdskip said:
Any ideas of how to get testing to see just how much damage I did? Where would I start?
Click to expand...
I'd start by doing a visual inspection of as much as you can. Likely the charging path between the alternator and battery is toast, which may have also taken out power to the rest of the electrical system. For now, just disconnect the fried sections (plus of course the alternator & Pertronix, plus any other electronics you have installed).

The details of how to proceed depend somewhat on which TR6 you have, but basically try to reconnect the rest of the system and see how many other things don't work. You might want to make your initial connection to the battery through a resistor of some sort (like an old headlight bulb) in case there is a short to ground somewhere.

The alternator itself is almost certainly dead, but there is some chance the Pertronix survived. But I would work on the other lights & whatnot first, to gauge how bad the harness is, before tackling the ignition & alternator.

You might also think about getting the battery cable color coding straightened out on both cars, so that red only connects to positive and black only connects to negative.
 
The wrath of the evil Lord! It always worried me that there were a number of unprotected circuits on the TRs - to the alternator and the ammeter for instance. I installed a 50A circuit breaker right next to the starter solenoid as a "main breaker" for the entire system. Haven't had to rely on it yet though. Also it has a manual trip feature so can isolate the electricals if I leave it parked for any period (also provides a bit of theft protection).

Rob.
 
One advantage of the simpler early cars... the PO of my TR4 installed the battery backwards. I drove it home and for several days before I realized this. Flipped it around, repolarized the generator and all was well... even the dead AM radio came back to life.

Obviously a 6 with an alternator & pertronix will not be so tolerant of such treatment.
 
So do you think the damage would be confined to the alternator, or is it likely that I fried some of the wires before the alternator?

Is it as simple as pulling the alternator and having a repair show determine if it is toast?

Is there a "path" of damage to follow?
 
Re: Fry a TR6 electrical system in these easy step

tdskip
I can do it in less than 3 easy steps and without reversing battery polarity.............
Regards
Craig
 
Skip,
Here's a dumb question because your posts of your problem are vague about how dead your car is. Did you check the fuse box and see if all your fuses are blown?

What have you checked so far? If your car isn't running, why do you think the alternator is fried? If you see obvious signs of melted harness wires, you have to start with a new harness and go from there.

Did you test the battery for life? That is where you begin if you don't see any melted wires. That's where the whole thing started. Then move outward from there. You have to start with a known power source and then test, test and more test.
 
Thanks for the ideas!

Stirkle said:
Did you check the fuse box and see if all your fuses are blown?
Click to expand...

I did, and none of the fuses were blown.

Stirkle said:
If you see obvious signs of melted harness wires, you have to start with a new harness and go from there.
Click to expand...

No obvious signs of melting, but to be honest I was so disgusted at my brain fade I walked away once it became clear I really messed up. I'm going to pick it up again this weekend.

Stirkle said:
Did you test the battery for life? That is where you begin if you don't see any melted wires.
Click to expand...

I did properly connect the battery but nothing on the car work. I assumed the battery was OK still, but maybe if I'm ridiculously lucky that is the problem.

I'm going to use your and the other guys ideas as my plan of attack and see how far I get.

Thanks again for the help!
 
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