Section : General

General Acclaim messages

Battery testing

Posted By : Dan Owen, 11-May-2006, 11:20am

ANOTHER problem with the old man's Acclaim. Battery holds a healthy 13v but won't turn the engine over well if at all. Starter has been checked by local auto sparks and pronounced fit. Still 13v at battery, won't start with spare battery (which might not be much good itself I guess) but goes when jump started.

So it seems the battery while seemingly OK cannot manage a heavy discharge to actually start the engine. Is there any way of checking this out without lashing out on a new battery?

PS Probably isn't the earth. Knowing the old man he will have connected the jump leads straight to the battery terminals!

Followups :

Battery testing

Posted By : Graham Bostock, 11-May-2006, 01:16pm

Try measuring the battery voltage whilst tring to start the engine. If the battery voltage drops to 6 volts then you know it is the battery. If the battery voltage remains at 13 volts then there is a bad connection somewhere. I had a similar problem on my Spitfire and it turned out to be a poor contact in the solenoid. Or it could be the earth...

Graham
- Battery testing
  
  Posted By : Kevin Rochfort, 11-May-2006, 01:22pm
  
  When testing the battery voltage under load to determine if it is the battery, or the wiring, don't forget to measure the voltage at the battery posts, and not the clamps onto the posts, as the bad connection could be between the post and the clamp.
  - Battery testing
    
    Posted By : Dan Owen, 11-May-2006, 05:49pm
    
    Thanks guys, will try that later.
    - Battery testing
      
      Posted By : Dan Owen, 12-May-2006, 02:17pm
      
      Yep... battery is knackered! Mind you-it's been on the car for 4 or 5 years and over 40K. Didn't look new then either!
      - Battery testing
        
        Posted By : Bill Goodwin, 14-May-2006, 07:09pm
        
        Many a weak or old battery will test ok with only a volt meter. You will need a load tester to be sure. If you try to jump a verry weak or dead one most times the bad will cosume the good one and still no start.
        
        Battery testing
        
        Posted By : Dan Owen, 15-May-2006, 11:38am
        
        What's a load tester (apart from &163;&194;&163;&194;&163;&194;&163;&194;&163;&194;&163;&194;&163;xpensive) as I have never heard of it?
        
        Battery testing
        
        Posted By : Kevin Rochfort, 15-May-2006, 11:51am
        
        A "load tester" is something that most garages and tyre & exhaust centres that retail batteries have.
        
        It is a device with a pair of handles and prongs that are about the distance between the battery terminals apart, joined by a low (ish) resistance high current wire, and a volt meter. The prongs are poked against the battery terminals, and a high current flows through the device and the voltage is measured on the volt meter to say if the battery is good or knackered.
        
        Battery testing
        
        Posted By : Dan Owen, 15-May-2006, 12:08pm
        
        Aah right, one of THOSE.
        
        Battery testing
        
        Posted By : Bill Goodwin, 15-May-2006, 08:21pm
        
        Kevin is right. Over here a good one cost around $35.00 US. All good shops have them and most will test your battery for free.
        
        Battery testing
        
        Posted By : Dan Owen, 16-May-2006, 12:10pm
        
        A free test ain't much good if you can't get started to go there...
        
        Battery testing
        
        Posted By : Paul Mason, 13-Mar-2007, 10:48pm
        
        If you unbolt the clamp and disconnect the battery you can take it to them in another vehicle for a test. lol