• Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

Why did my optima fry???

  • Thread starter Thread starter my66coupe
  • Start date Start date Nov 21, 2004
M

my66coupe

Founding Member
Apr 30, 2002
1,134
0
36
Arizona fountain hills
Nov 21, 2004
#1
  • Nov 21, 2004
  • #1
Well....here's the story, I recently installed a electric fan, powered by a relay, a new Voltage guage read 12 volts at idle, 14 while cruising, and would bouce like hitting the rev limiter on the tack at WOT. If i reved it in park it would sometimes get up to 16 volts.... anywho, I had a old set of michelin xh4s laying around and a bunch of my friends and I are putting a video together for our senior year. I did a massive break stand for 40seconds, feathering the throttle never keeping it at WOT. Well, i got home fine, no problems whatsoever. The next morning i go to fire it up....takes a few good cranks, drive, stop and dies, wouldnt fire up, got it to fire up 5 min later. drove some more got gas, then stuck at the gas station........... Finally got it home that night. parked it and realized my battery was dead the next morning. I went to charge the Optima red top with a 1.5 trickle charger, and it would not accept the charge....Swapping in my trusty costco battery the car fired right up with out any problems and is running excellent. What gives? Did the long term voltage of the breakstand blow something? Thanks guys

Mike
 

WORTH

20+ Year Stangneter
Nov 18, 2002
2,166
44
98
Cape Cod, Ma.
Nov 21, 2004
#2
  • Nov 21, 2004
  • #2
my66coupe said:
Well....here's the story, I recently installed a electric fan, powered by a relay, a new Voltage guage read 12 volts at idle, 14 while cruising, and would bouce like hitting the rev limiter on the tack at WOT. If i reved it in park it would sometimes get up to 16 volts.... anywho, I had a old set of michelin xh4s laying around and a bunch of my friends and I are putting a video together for our senior year. I did a massive break stand for 40seconds, feathering the throttle never keeping it at WOT. Well, i got home fine, no problems whatsoever. The next morning i go to fire it up....takes a few good cranks, drive, stop and dies, wouldnt fire up, got it to fire up 5 min later. drove some more got gas, then stuck at the gas station........... Finally got it home that night. parked it and realized my battery was dead the next morning. I went to charge the Optima red top with a 1.5 trickle charger, and it would not accept the charge....Swapping in my trusty costco battery the car fired right up with out any problems and is running excellent. What gives? Did the long term voltage of the breakstand blow something? Thanks guys

Mike
Click to expand...

some battery chargers will not charge a battery if the voltage is too low, it trips their polarity protection circuit. try a different charger before you condemn it.

16 volts seems a bit high, and 12 is too low for idle, you may have a junk voltage regulator. Takes some readings with the good battery in it and see what you get. It should charge at least 13 at idle and maybe 14.5 at RPM
 

pabear89

Active Member
Apr 15, 2003
2,126
0
46
High in the Hills of So Ca with the Voices in My H
Nov 21, 2004
#3
  • Nov 21, 2004
  • #3
Well you could do the trusty old fingernail file on the points of the voltage reg or replace it. your call.
But if you remove the reg cover you'll see the contact points inside (provd its the old style and not elec.)
take a ladys fingernail file and LIGHTLY clean the contacts and the grounding point of the reg.
Test to see if your Bounce has gone away.
or spend the 15 bucks and replace it.

PB
 
You must log in or register to reply here.

Similar threads

K
Engine 2000 Mustang GT - Fuel issue post-blown spark plug repair
  • kenster1092
  • Feb 26, 2026
  • SN95 4.6L Mustang Tech
Replies
4
Views
333
SN95 4.6L Mustang Tech Mar 10, 2026
kenster1092
K
B
'03 GT Fuel Pump/Pressure/Delivery Issue
  • Brodach
  • Oct 21, 2025
  • SN95 4.6L Mustang Tech
Replies
8
Views
876
SN95 4.6L Mustang Tech Oct 31, 2025
gkomo
is my car dead
  • kenzo0315
  • Jun 30, 2025
  • SN95 V6 Mustang Tech
  • 2
Replies
29
Views
1K
SN95 V6 Mustang Tech Jul 8, 2025
kenzo0315
K
Electrical charging issue
  • knucklehead11
  • Jul 15, 2024
  • SN95 V6 Mustang Tech
Replies
5
Views
884
SN95 V6 Mustang Tech Jul 16, 2024
Mcmahst
My Optima YellowTop
  • 1hot87gt
  • Aug 25, 2023
  • 1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk-
Replies
18
Views
2K
1979 - 1995 (Fox, SN95.0, & 2.3L) -General/Talk- Oct 21, 2023
1hot87gt
Share:
Bluesky Email Share Link
  • Mustang Forums
  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech
Menu
Log in

Register

  • Forums
  • What's new
  • Media
  • Resources
  • Contact
  • Sponsor
X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?

X

Privacy & Transparency

We use cookies and similar technologies for the following purposes:

  • Personalized ads and content
  • Content measurement and audience insights

Do you accept cookies and these technologies?