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battery cables

As I've already noted, factory information does seem to confirm that all Mk3 Spitfires were negative ground. But there are some sources around the Net that seem to indicate that the Mk3 dates from January 1967 (I've nothing in front of me to confirm or dispute that date), so ??? Your car is pretty early (FD2081?), but.... ?

I'm guessing that the cables are not original Lucas "Helmet" style terminal ends? A: they usually were clearly marked + or -, and B: they're usually a slightly different size (+ terminal a tiny bit larger, as I recall). If the cables are generic replacements, it's certainly possible that someone reversed a battery sometime in the last 40 years.

Also not conclusive after 40 years, but how are the small wires on the coil connected? Ideally, the small wire from coil to terminal would come from the - side of the coil on a negative ground car. Yes, the car will run either way, but generally it runs better when the coil is wired properly.
 
Andrew Mace said:
But there are some sources around the Net that seem to indicate that the Mk3 dates from January 1967
My understanding is that March was the 'official' introduction date in the US, even though the first Mk3 cars were produced several months before that (ie January).

Given the US dealers' propensity for selling next year's cars starting in October (or even earlier), that would make almost 6 months worth of "1967" Mk 2s.
 
Andrew Mace said:
Maybe you do need a bigger magnifying glass, though.
More likely, I should quit buying them at the $.99 store
grin.gif
 
hi randall,

i find that in my line of work, the cheap glass of the corner store seem to work the best.
the commission number is fd 2081 L, with a body number of 2264fd .

as far as the coil go's, the negative wire is going to the generator,
and the positive go's off into the harness into the firewall.

tom
 
sabot said:
as far as the coil go's, the negative wire is going to the generator,
and the positive go's off into the harness into the firewall.
Assuming you mean distributor instead of generator, that would indicate the coil is wired for negative ground; and someone has installed the battery backwards.

If you switch it back, you'll probably have to repolarize the generator, but nothing else should be required.
 
TR3driver said:
sabot said:
as far as the coil go's, the negative wire is going to the generator,
and the positive go's off into the harness into the firewall.
Assuming you mean distributor instead of generator, that would indicate the coil is wired for negative ground; and someone has installed the battery backwards.

If you switch it back, you'll probably have to repolarize the generator, but nothing else should be required.

oops, yer right, i meant distributor.

how doe's one repolarize a generator?
tom
 
I'm not sure how your Spit is arranged, but usually, you can just pull the wire off the 'F' terminal on the regulator and brush it against the 'A' or 'A1' terminal. No need to have the engine running or ignition on. You might see some modest sparks, that's OK. Put the wire back on the 'F' terminal, start the engine and see if the generator light goes out. If so, all is well.

But if it's like the Sports 6, where the regulator is under the dash, then it's probably easier to momentarily connect a jumper from the battery to the 'F' terminal on the generator.
 
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