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Electrical Drain ????

1K views 8 replies 4 participants last post by  745turbo 
#1 ·
Hi everyone,
i hope someone here can help me out


i took my two young sons out in our 740 estate (89) yesterday and on our way to our destination the car just lost all power and died on me

when i tried to restart it there was nothing in the battery at all not even enough power to open/close a window.
Thankfully we had broken down near a car dealership and one of the guys came out with a spare battery to give us a jump start. With the new battery attatched she fired up straight away and ran a sweet as ever!
However when we detatched the jump cables the old girl died straight away !!!!
The "salesman" said it must be my battery that is the problem. SO, i bought a new one from him, fitted it and away we went with no more problems.

Or so i thought.

We reached our destination, had a good day and in the evening started our return trip home.
About half way home the radio stopped working, closely followed by the Rev counter,temp gauge and instument panel lights. then i started to loose engine power and after a few hundred yards had to pull over onto the hard shoulder and the engine just died again !!!
I tried to turn her over but again the New battery was totaly flat!
then i had to call out a tow truck to bring me home
(£223
)

I have had the new battery on charge over night and i just know that when i go out and fit it this morning she will fire up and run with out skipping a beat (as usual)
But, i feel sure it will only be a matter of a short while until all power is lost again..........................

Has anyone got an idea as to what i am up against here ?

I love my car and feel lost knowing i cant trust her at the moment


Any help would be greatly appreciated.

Thanks,

Phil
 
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#2 ·
Re: Electrical Drain ???? (PHLI72)

Just as i thought !

Went out there this morning with a fully charged battery and she started up first turn of the key GRRRRRR


Took a drive to my local auto store and had the alternator and battery checked out...................All A1.

Now i'm really stumped
 
#3 ·
Re: Electrical Drain ???? (PHLI72)

Until you can diagnose the cause just install a quick-disconnect switch on the battery negative post and unhook at night. This will mess up your radio and alarm but will tell you if the electrical system has a major shortage problem. It is unlikely that a fully-charged, healthy battery could rapidly discharge without creating a fire or damaging electrical components.
 
#4 ·
Re: Electrical Drain ???? (gdill2)

Thanks for the reply


The problem is, it doesnt seem to be draining while the car is not in use !!!

It only seems to happen when the car is being used for lengthy time ie on a long run.
If this is the case the cause could have been around for some time as it's been a while since ive done a long trip.
I think i will try and source another battery and take it with me wherever i go for now , just incase it happens again and keep the trips to a minimum
 
#5 ·
Re: Electrical Drain ???? (PHLI72)

The plot thickens.

Just been out at the car, had it running with a digital voltmeter on the battery all the time.
Ran ok for about 30 mins with the meter at a steady 12-12.5 V.


Then, without me touching anything, the voltage started to drop, very slowly but steadily until at went down to 10.5 V. the instrument panel started to die (i thought here we go again) so i turned the engine off.


According to the meter, the battery started to recover and slowly the voltage climed back up to just over 12 V.
However, when i tried to start the engine again, it was dead as a dodo !


I left it for about 10 mins and tried again, there was just enough power to fire it up and straight away the voltage droped steadily.

I turned it off and removed the battery, then checked the battery voltage it was climbing rapidly and at the moment is reading 14.05 Volts !!!!!!!!!!!


(how can it be reading 14 volts but wont start the car ??)

So, now i.m sitting here scratching my head...................

What is going on ?????

PLEASE HELP............Somebody !
 
#6 ·
Re: Electrical Drain ???? (PHLI72)

Since you've seen problems at the starter and other places in the electrical system, but the battery itself is OK, the fault is probably somewhere near the battery.

The simplest thing would be an intermittent ground, possibly from some corrosion hidden from sight.

Use your voltmeter to check the current from the positive terminal to any ground on the car. Try shifting the cables around (be careful not to cause a short!) to see if the voltmeter registers a change.
 
#7 ·
Re: Electrical Drain ???? (PHLI72)

For what you describe I would say the problem is the Alternator or the voltage regulator in it.

I had a similar problem with my car. When I was driving, the needles in the instrument cluster would start swinging and the lights would dim and then the car would stop running. I took it two times to the mechanic for repairs, in the first, they changed the voltage regulator but a couple of days later I was stranded again. I was surprised since the batt light never came on.

In the end thay re-cored or something my alt to 70 amps (from 50) and took out a ground cable that goes directly to the batt. So it seemed to be a problem of a too low amp that with the age of the car and the small loses that come with it did not properly charged the batt plus a bad ground that they were not able to correct and had to "direct" wire.

I think in some places you just send your alt and they give you a repaired one so you don´t have to battle like me.
 
#8 ·
Re: Electrical Drain ???? (745turbo)

745turbo,

Thanks for the reply


Made a few phone calls last friday, £118 for a new alt Or £30 for a used one from my local Volvo breakers. Thought "what have i got to loose (yeah , i know , 30 quid . LOL)

Cycled round to pick one up, fitted it Sat Morning.

IT is now Tues Morning and she hasn't skipped a beat, touch wood


Thanks for the advice.
Think theres a lesson to be learned here. Dont believe everything a "mechanic" tells you and go with your gut feeling.

When i had the old one off i took the Voltage reg off and looked at the brushes.......very worn, My book says 5 MM min length and they were dead on 5 mm. so it may well have been that but ......i dont care now LOL

Thanks again,

Phil
 
#9 ·
Re: Electrical Drain ???? (PHLI72)

PHLI72,

Glad to hear your car is well again. I hope you enjoy many more miles driving it.

I sure do driving mine!
am glad not to have given up on her
when she left me stranded two times in a week, only time in 16 years it had done so and everybody told my the time had come.....but as you say trusted my gut feeling and now it feels like its going to outlive many newer cars. If you are like me, then most of your family and friends do not understand why you drive that car instead of a newer one.

If your answer is "because driving it makes me happy in a way a new car could not" then I know why we both post here
volvo http://********************/smile/emlove.gif

 
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