Odd (I Think) Electrical Question

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ARCHINSTL
Goldie Forever
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My tercel:: Goldie is a 1986 SR5 attualmente con Weber/also owned the first T4WD in STL in late '82
Location: Kirkwood, a 'burb of St. Louis

Odd (I Think) Electrical Question

Post by ARCHINSTL »

So - as I was working on the Weber installation - the ONLY electrical thingies I unplugged were the phenolic heater plate black plug and the big green carb plug (choke/solenoids). The other switches to all of the emission gizmos were still connected.
No other electrical items were drawing current, save the digital clock. Nothing was shorting or emitting Lucas smoke.
For ? reason, I had measured the battery at the outset at 12.4 volts.
Over the course of 3-4 nights, I noticed the interior lights growing dimmer and dimmer, and finally to a bare glow.
Before removal, it tested for a parasitic draw of only 7.8 milliamps (from the clock), which is as it should be.
And upon removal it was showing 4.3 volts, prior to cleaning and bench full-charging,
Now, since the reinstallation and subsequent driving around testing the carb, the battery is showing its usual 12.5+ key-off volts and about 14.xx volts while the engine is running - with no loss of volts overnight.
The battery is about 3 1/2 years old, and has never shown a sign of weakness - especially during the weeklong periods the car was not used a couple of months ago.
Any guesses ? It's working fine, but I AM curious.
Tom M.
T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."
T.S. Eliot - "The Love Song of J. Alfred Prufrock"
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takza
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Re: Odd (I Think) Electrical Question

Post by takza »

Probably one of those situations where if it ain't broke don't fix it? I guess if the rad fan can be set up to run if the switch fails..maybe the engine elects draw current when all the wires are disconnected? :shock:
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Petros
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My tercel:: '84 Tercel4wd w/extensive mods
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Re: Odd (I Think) Electrical Question

Post by Petros »

a fully charged battery should show 13.2 volts (2.2v per cell x 6 cells) when the engine is not running. If it is only showing 12.5 volts and then slowly loses charge over several days, it sounds like one cells is dead, your battery needs to be replaced.

The battery should stay charged for 60 days, if a car sits for more than a month, it is a good idea to start it and allow it run for 10-15 if not drive it. Normally allowing it to sit for a month or two will not harm the battery. It should keep the charge or there is an internal problem with it. I have had to replace my Tercel battery twice in the last two years (under the 60 month warranty) because of them going bad just like you describe.
'87 Tercel 4wd SR5 (current engine swap project)
'84 Tercel 4wd (daily driver, with on going mods)
'92 Mazda MPV 4wd (wife's daily driver)
'85 Tercel 4wd DLX auto(daughter's daily driver)
'01 Honda Civic (other daughter's daily driver)
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ARCHINSTL
Goldie Forever
Posts: 6369
Joined: Sat Apr 30, 2005 1:52 pm
My tercel:: Goldie is a 1986 SR5 attualmente con Weber/also owned the first T4WD in STL in late '82
Location: Kirkwood, a 'burb of St. Louis

Re: Odd (I Think) Electrical Question

Post by ARCHINSTL »

Predictably - Petros posted presciently...pshaw!
The battery was unused for just two nights and went down to 4.5 volts.
Got a new AutoZone DuraLast "redtop" battery. Two-year free replacement and seven-year prorated warranty - $80.
Tested today after sitting since installation last night - 12.57 volts/engine off and 14.45 at idling - all at 28 degrees F.
The PO had installed a cheapie from WalMart (I will not enter a SleazeMart) - but it lasted for over 3 1/2 years.
Tom M.
T4WD augury?
"Oh, do not ask, 'What is it?' Let us go and make our visit."
T.S. Eliot - "The Love Song of J. Alfred Prufrock"
"Now and then we had a hope that, if we lived and were good, God would permit us to be pirates."
Mark Twain
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