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Re: electric problem

To: Dana Scribner <dscrib2@hotmail.com>
Subject: Re: electric problem
From: Pat Horne <pjhorne@mail.utexas.edu>
Date: Thu, 22 Jun 2006 21:43:17 -0500
Dana,

Most of my experience has been with 67.5 Roadsters, so I may be guessing 
exactly where things are in the high windshield cars.

You say that you swapped engines. Is the engine you put in the same type 
as what was in there car or did you swap in something new?

If you have 13.5V on the alternator output terminal, and 12.15V on the 
battery with the engine running, you have an open connection somewhere. 
Since you are able to start the car via the key (assumed), I suspect 
that all the lights, horn, etc also work. This says that the open 
connection is somewhere between the alternator and the dash.

One question before we get going. When you read the 2 voltages listed 
above did you use the same ground point? If not, the following 
troubleshooting may not help you. Recheck the voltages using the same 
ground. If you get the same voltage on the alternator and battery using 
the same ground, you have a bad ground.

There is a connector in the harness right against the firewall, to the 
left of the steering column, just about as far to the left as you can 
go. This connector is behind the triangle shaped piece of metal up under 
the dash. I think the White-Red wire goes through that connector. There 
is also another connector right there that connects the rear harness. 
That connector will have no affect on this problem. The pins for the 
White-Red wire may be corroded, burned or dirty. See what the pin looks 
like. An easy way to test this is to probe the back of each connector 
with the volt meter probe. You will find the problem when you find where 
the voltage is different on each side of the connector or wire. Be sure 
to watch the ammeter when you probe the connector as you may be causing 
the connector to make a better connection when you push the meter probe 
in, causing things to work.

If that connection looks good and has a voltage equal to the battery 
voltage on both sides, the problem is with the wire that runs through 
the firewall and to the alternator. Check the harness for signs of a cut 
harness from when you put the new engine in. I don't know where your 
alternator is located, driver's side or passenger's side but the 
White-Red wire runs down the left inner fender to the alternator 
)driver's side alternator, or on  across the upper radiator support and 
to the alternator Passenger's side alternator.

Let me know what you find.

Peace,
Pat

Dana Scribner wrote:

> I need some help, in more ways than one. I did an engine swap and 
> everything went fine except the battery is not changing. I have 
> swapped out alternators and regulators and I get the same reading at 
> the battery 12.15V. I get 13.5 v at the alternator and the same at the 
> white wire going into the regulator. I have pulled all the fuses and 
> it make no difference. I have cleaned all the grounds around the 
> engine and the connectors to the starter, alternator and regulator. 
> Now before I start with all the connections in the car is there a way 
> to narrow down where the problem might be? Like maybe disconnect a 
> harness and see if that makes a difference. If so what harness? Does 
> anyone have a suggestion?
>
> Dana S
>
> 1969 2000
>

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