Backwards Diode with 10-SI 12v conversion?

I have a 12V 8n with a Delco 10-SI alternator 3 wire conversion and just noticed that the diode seems to be backwards - the silver band is pointing towards the
dashboard rather than the #1 alternator terminal like the diagrams shos it should.

It's been like this for at least 2 years, and never a trace of trouble. The tractor starts well and never a bit of trouble with the battery staying charged. Can anyone
electrical explain to me how this can be? I'm not sure if I should dare flip the diode now, since it seems to be working so well the way it is
 
I would leave it alone, but I know nothing and claim to know nothing--I have one installed the right way and it still drains--which made me think the drain was caused somewhere else--all test indicated alternator drain-so I just added a toolless battery cable disconnect cable end--now no drain obviously..when it's going to just sit I disconnect the one cable--it sits unused all the time..Just one of my expensive toys that I need to sell...sorry, lot more rambling than u asked for--but it's free......
 
My first thought was "if it ain't broke, fix it until it is!"
On the other hand, is it actually charging the battery?
A 12V battery will run an N for months without charging.
Have you checked that the battery is really charging?
That's what I would want to do.
 
Interesting thought. The machine doesn't have a working volt or ammeter, so I suppose it is possible it hasn't been charging, but I'll be real surpised if it turns out not to
have been.

I didn't notice the diode was backwards until I undid half the wiring, so I got to put it together before I can do any tests, but I'll try an (analog) voltmeter on it soon as I
do.

Is that all having the diode backward would do, make it not charge? I was under the impression it would cause other problems as well.
 
(quoted from post at 20:59:53 09/11/16) Interesting thought. The machine doesn't have a working volt or ammeter, so I suppose it is possible it hasn't been charging, but I'll be real surpised if it turns out not to
have been.

I didn't notice the diode was backwards until I undid half the wiring, so I got to put it together before I can do any tests, but I'll try an (analog) voltmeter on it soon as I
do.

Is that all having the diode backward would do, make it not charge? I was under the impression it would cause other problems as well.
es, I can see it causing "other" problems, BUT, I am a huge proponent if "If it ain't broke , don't "fix" it".
 
Same with my Jub, still drains with diode....if diode reversed no charge to battery so I know I have it directional correct.. So I added a cut out switch in the same wire (big wire from the 3 wire alt)....must be on to start, then can be switched off to stop charging to battery but engine runs. Run awhile, switch on and amp gauge shows decharge until battery is back up. When amp gauge levels out, turn alt off again or leave it on, doesn't matter. I put switch above key so it is habit now to switch off whenever key is off. Someday I am gonna figure it all out, meanwhile it works fine.
 
"So I added a cut out switch in the same wire (big wire from the 3 wire alt)"

I'm not sure I understood you correctly but if this is the "big wire"
from the charging stud on the alternator that's not the wire the
diode goes in. The diode (or lamp) goes in the excite wire on
the #1 spade terminal. Not saying that would fix your drain though.
 
The diode in the "excite" circuit has NOTHING to do with battery drain once the ignition switch is turned "off".
 
If your alternator is in fact working/charging it MAY be a "one-wire" unit that doesn't need a connection to the #1 terminal to excite/charge, so therefore the backwards-connected diode would be doing NOTHING, and at the same time hurting/affecting nothing.
 

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