ok, speedy jim--- my turn to ask

73 bus with 1800. alternator with voltage regulator mounted in the engine
bay. as far as i can tell, it is the factory wiring harness to the reg.

one wire, which comes off of d+ goes to the reg. and up to the gen warning
light. the gen light stays on with no key in yet goes off when the key is
turned to the first click.
all of this worked before. we pulled engine tranny and did all sorts of
repairs in the process-- so mebbe we screwed somthing up.

the wire from d+ has 12 volts with the engine off -- crap, didn't check to
see if it does with the engine running ! is there supposed to be 12 volts
when engine off ??
it doesn't seem like there should be since the gen light is thus lit.
muir says-- fried reg. but we have two and tested it with the other one and
same thing.

canya shed some light mebbe ???

tia bob

Bob Mrazik wrote:

> 73 bus with 1800. alternator with voltage regulator mounted in the engine
> bay. as far as i can tell, it is the factory wiring harness to the reg.
>
> one wire, which comes off of d+ goes to the reg. and up to the gen warning
> light. the gen light stays on with no key in yet goes off when the key is
> turned to the first click.
> all of this worked before. we pulled engine tranny and did all sorts of
> repairs in the process-- so mebbe we screwed somthing up.
>
> the wire from d+ has 12 volts with the engine off -- crap, didn't check to
> see if it does with the engine running ! is there supposed to be 12 volts
> when engine off ??
> it doesn't seem like there should be since the gen light is thus lit.
> muir says-- fried reg. but we have two and tested it with the other one and
> same thing.
>
> canya shed some light mebbe ???
>
> tia bob
>
>
Pull the wire to the light off of D+.
Then see if there is voltage on D+.
If so, there is a bad diode in the Alt.

Speedy Jim
http://www.nls.net/mp/volks/

there is voltage. can the diodes be replaced easily ??

Bob Mrazik wrote:

> there is voltage. can the diodes be replaced easily ??
>
>

Ya got me there.

GOOGLE around a bit.

Jim

Speedy Jim wrote:
>
> Bob Mrazik wrote:
>
> > there is voltage. can the diodes be replaced easily ??
> >
> >
>
> Ya got me there.
>
> GOOGLE around a bit.
>
> Jim

Replacing individual diodes is a pain, and requires a massive soldering
iron or something.
They are hard soldered onto a "diode bridge", a round plastic&metal
holder and you usually replace the whole bridge. It holds 6 diodes in
total.

Jan

On Mon, 16 May 2005 23:21:55 -0400 Speedy Jim > wrote:

> Pull the wire to the light off of D+.
> Then see if there is voltage on D+.
> If so, there is a bad diode in the Alt.

Uhhh, but on an alternator the D+ terminal runs directly to the
battery, so it is always hot....

-
-----------------------------------------------
Jim Adney
Madison, WI 53711 USA
-----------------------------------------------

Jim Adney wrote:

> On Mon, 16 May 2005 23:21:55 -0400 Speedy Jim > wrote:
>
>
>> Pull the wire to the light off of D+.
>> Then see if there is voltage on D+.
>> If so, there is a bad diode in the Alt.
>
>
> Uhhh, but on an alternator the D+ terminal runs directly to the
> battery, so it is always hot....

Ummmm, you're thinking of "B+"

Speedy Jim
http://www.nls.net/mp/volks/

On Wed, 18 May 2005 09:20:23 -0400 Speedy Jim > wrote:

>Jim Adney wrote:
>
>> On Mon, 16 May 2005 23:21:55 -0400 Speedy Jim > wrote:
>>
>>
>>> Pull the wire to the light off of D+.
>>> Then see if there is voltage on D+.
>>> If so, there is a bad diode in the Alt.
>>
>>
>> Uhhh, but on an alternator the D+ terminal runs directly to the
>> battery, so it is always hot....
>
> Ummmm, you're thinking of "B+"

Oops, you're right!

-
-----------------------------------------------
Jim Adney
Madison, WI 53711 USA
-----------------------------------------------