Dan Borrego wrote:
>
> My 77B's coil gets hot after running for about five minutes. Not just a
> very warm temp, but more of a too hot to touch temperature. Is this normal?
> I'm wondering if the coil might be bad, or going bad.
> The previous owner had the electronic ignition in the distributor replaced
> (I suppose the original was giving him some problem). Could the coil simply
> be hooked up incorrectly?
> The car hasn't given me any problems yet, and I'd like to straighten out
> this situation before I get stranded on a road trip. If anybody on the list
> has had to deal with this (or knows how to), I would welcome your thoughts
> or comments.
> Thanks,
> Dan
Your car should probably have a six-volt coil with an external ballast resistor
(actually a length of resistive wire in the loom). Have a look at the part
numbers
- the original coils were HA12 (12v) and 16C6 (6v) i.e. the last bit of the
part
number seems to indicate the voltage. With the ignition on turn the engine
till the
points are closed and measure the voltage on each side of the coil. You should
see
ground on one side and about 6v on the other of a 6v coil, ground one side and
12v
the other of a 12v. If the points are open you will see 12v (with a
standard high-impedance meter) both sides of both types.
If you see ground on one side and 12v on the other on a 6v coil it will get too
hot,
and probably be burning the points as well. The 6v is boosted to 12v on
starting by an
extra wire taken to a special contact on the solenoid. If someone has
connected this
to a hot terminal on the solenoid it could explain your problem. Or the coil
could be
breaking down inside and partially shorting-out. Check the resistance if you
can,
about 3.1 to 3.5 ohms for the 12v and 1.43 to 1.58 for the 6v.
PaulH.
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