ascMcLaren Enthusiasts Forum Index ascMcLaren Enthusiasts
An asc McLaren forum for ALL Mustang and Capri based cars modified by Automotive Speciality Corporation, a Division of American Sunroof Corporation.
(a trademarked corporation) with no affilation to this site.
 
 AlbumAlbum   FAQFAQ   SearchSearch   MemberlistMemberlist   UsergroupsUsergroups   RegisterRegister 
 ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Battery slowly running down

 
Post new topic   Reply to topic    ascMcLaren Enthusiasts Forum Index -> ASC Discussions
View previous topic :: View next topic  
Author Message
randyveach



Joined: 24 Aug 2014
Posts: 50
Location: Round Rock, Texas

PostPosted: Fri Aug 07, 2015 10:07 pm    Post subject: Battery slowly running down Reply with quote

I've had the battery checked at 3 different places. All cells are good. I've got a slow leak somewhere and before I start looking for it, I thought I'd ask if this is a known problem for 1986 asc McLarens.

Thanks in advance.
_________________
Randy Veach

1986 ASC McLaren (Red Convertible) # 0058

Believe in your dreams
Back to top
View user's profile Send private message Album
5280Capri



Joined: 06 Feb 2014
Posts: 7
Location: Denver,CO

PostPosted: Fri Aug 07, 2015 11:12 pm    Post subject: Reply with quote

I am not aware of any particular problems with these cars.
First suspects would be aftermarket accessories, alarm, audio, etc. These are known to create parasitic losses.
Otherwise pull a battery cable and put an ammeter from the battery post to the cable you just disconnected. Next start pulling fuses to isolate which circuit is the problem and go from there.
Back to top
View user's profile Send private message Album
svo413



Joined: 29 Aug 2004
Posts: 752
Location: San Mateo, California

PostPosted: Sat Aug 08, 2015 6:46 pm    Post subject: Lights Reply with quote

I often have a problem with my knee bumping the interior light switch. Check the hood light too.
_________________
Kevin Gold card MCA Judge for Fox Body
85 ASC Vert #612205
88 ASC Vert #542 20,550 miles
84 SVO 24,000 miles, 84 GT Turbo Vert.
03 Mach I, 89 LX Vert, 74 Mustang II
14 CA Special, 69 Mustang coupe, 07 GT500
67 T-bird, 15 F150 Tuscany, 16 F250
Back to top
View user's profile Send private message Send e-mail Album
plumkrazy



Joined: 27 Jul 2005
Posts: 1126
Location: Ann Arbor Michigan

PostPosted: Mon Aug 10, 2015 10:17 am    Post subject: Reply with quote

Seen a couple of Fords that have Alt. drain's
Back to top
View user's profile Send private message Album
negusm
Site Admin


Joined: 25 Aug 2004
Posts: 5183
Location: Charlotte, NC

PostPosted: Mon Aug 10, 2015 7:43 pm    Post subject: Reply with quote

5280Capri wrote:
I am not aware of any particular problems with these cars.
First suspects would be aftermarket accessories, alarm, audio, etc. These are known to create parasitic losses.
Otherwise pull a battery cable and put an ammeter from the battery post to the cable you just disconnected. Next start pulling fuses to isolate which circuit is the problem and go from there.


Exactly right. This will take you a small amount of time and you will zero right into the culprit.

If it is not a parasitic drain, you have a charging problem.

Is the battery draining with the car just being in the garage? What are the symptoms?

-Mike
_________________
1985 ascMcLaren Coupe - Midnight Blue
Under Restoration
Back to top
View user's profile Send private message Send e-mail Visit poster's website Album
crewleader56



Joined: 25 Jun 2015
Posts: 2
Location: St. Peter, MN

PostPosted: Mon Aug 17, 2015 3:13 am    Post subject: Slow battery drain Reply with quote

I had a similar problem. I ended up finding a poorly crimped positive battery cable (factory crimp). It only acted up when I had everything on including the fog lights. Alt tested good and previous owner had installed a new battery a week before I bought it. It grabbed the negative cable and pulled it out of the replacement end with little effort so reattached that first. Then I yanked on the pos factory end and pulled the cable right out with less effort. Had about two strands with arc marks that were powering the whole car. Install new positive cable and the starter whirled the engine over like the day it came from the factory.

It may not be your problem but worth looking at.
Back to top
View user's profile Send private message Album
heat4copper



Joined: 03 Jan 2017
Posts: 4
Location: Bronx

PostPosted: Wed Jan 04, 2017 12:09 pm    Post subject: Reply with quote

I also had a similar problem, like Crewleader56 noted. In my case, I ended up replacing a battery https://www.carid.com/batteries/, as something was wrong with the terminal. I must say, I was so irritated with constant electrical problems, that was even glad that new battery solved it all.

Last edited by heat4copper on Fri Jan 20, 2017 2:09 pm; edited 3 times in total
Back to top
View user's profile Send private message Album
negusm
Site Admin


Joined: 25 Aug 2004
Posts: 5183
Location: Charlotte, NC

PostPosted: Wed Jan 04, 2017 4:11 pm    Post subject: Reply with quote

But those are not parasitic drains.

What you would see is that the battery is fully charged but yet, won't crank the starter motor.

*BUT*, it is EASY to misdiagnose a bad cable as a parasitic drain so you have to do the ammeter check to be sure.

*IF* the ammeter (while the car is off) shows NO drain (or only a milliamp or two for something like a clock) then we are not dealing the a parasitic drain and instead we're talking bad battery cables.

Years ago I had the issue where the car would start all week...except once and a while I would get "click click click"....like a dead battery.

I freshened up the terminals on the battery, and it would start. Next time, that didn't work so I had the battery tested...it was fine. But a week later had the same issue. Tested the alternator...it was fine. Probably tried a new starter Solenoid. It would fail to start more often and I somehow figured out if I turned on the headlights for a minute...then the car would fire up.

Finally my dad, took a look and he grabbed the positive battery cable and bent it...and all you heard was crackling inside like dry leaves...internally the cable had corroded so bad it was down to a couple of good strands. Outside, the cable looked perfect.

Later I found the starter battery cable doing the same thing.

Yeah, if you still have original cables, SUSPECT them. Pos/Neg battery AND the starter cable.

BTW turning your headlights on, will temporarily REVERSE corrosion in the electrical system. It was enough to allow me to get enough juice through to get the car started.

-Mike
_________________
1985 ascMcLaren Coupe - Midnight Blue
Under Restoration
Back to top
View user's profile Send private message Send e-mail Visit poster's website Album
heat4copper



Joined: 03 Jan 2017
Posts: 4
Location: Bronx

PostPosted: Thu Jan 05, 2017 7:14 am    Post subject: Reply with quote

Wow, I haven't checked the cables then and simply threw the battery away. Honestly, I would never think, that if the cable looks fine, it may be bad inside... Bad for me, looks like the battery was not that bad then. Anyways, thanks, next time will watch it more carefully.
Back to top
View user's profile Send private message Album
negusm
Site Admin


Joined: 25 Aug 2004
Posts: 5183
Location: Charlotte, NC

PostPosted: Thu Jan 05, 2017 6:20 pm    Post subject: Reply with quote

Yeah, and that's the insidious thing about it. You pull the cable off, wiggle it a bit, clean it, put it on and things work for a bit. So it's hard to tell what is messed up where.

-Mike
_________________
1985 ascMcLaren Coupe - Midnight Blue
Under Restoration
Back to top
View user's profile Send private message Send e-mail Visit poster's website Album
svo413



Joined: 29 Aug 2004
Posts: 752
Location: San Mateo, California

PostPosted: Thu Jan 05, 2017 11:24 pm    Post subject: Battery Reply with quote

I had a Motorcraft battery with a loose connection inside. Put jumper cables on it, was ok, took the off and it was bad.

Take the bulb out on the hood light too. No trunk light on our cars.
_________________
Kevin Gold card MCA Judge for Fox Body
85 ASC Vert #612205
88 ASC Vert #542 20,550 miles
84 SVO 24,000 miles, 84 GT Turbo Vert.
03 Mach I, 89 LX Vert, 74 Mustang II
14 CA Special, 69 Mustang coupe, 07 GT500
67 T-bird, 15 F150 Tuscany, 16 F250
Back to top
View user's profile Send private message Send e-mail Album
Display posts from previous:   
Post new topic   Reply to topic    ascMcLaren Enthusiasts Forum Index -> ASC Discussions All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group
Number of shameful bots caught by Anti-Spam ACP: 474