Dead Battery?

On way home from the workhouse today! Story from the top

1958 SII 88(86?) Petrol Start the engine (first push) @ 17:30 Drive 1-2 miles and attempt to cross the Cov Rd. in B'ham. Stall the Engine on Central Res! Push the Start lights (Oil & Gen) dim!!! Not a purr but silence try again light dim but no purr! Call Home going to be late! Call RAC to explain the problem. Within 30mins RAC man arrives. Pulls up ahead of me and lights up! Show him whats wrong! Out comes his Jump Leads & black box!. Press the start & purr turn on lights Etc. All go!! RAC man gets out his "Fluke" and 12.25V on tick over no lights Across Battery 12.45V when rev up motor. 12.25V with Side lights on & Rev. All running put it all back in Van. I follow him to "The Swan" he then follows me to "Top of my Street" I get home (thanks to RAC) Park up on drive turn off. Try to turn back on "No Purr" Battery charger out & plug in All lights on to 6 Amps!!! After 3 hours loose 1 & 2 Amps LED's Question? Battery Knackered? Gen-y Knackered? Charging Cct Knackered? Anyone suggest best point to start from Battery- Genny- Charging Cct. Or attack from another point?

3645 Echo Victor

Reply to
Vicky & Alan
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For "Genny" read Dynamo!! Senior Moment!

Reply to
Vicky & Alan

It still has the Dynamo fitted? or do you have an alternator?

This reading is too low to charge a battery, the dynamo/regulator should be putting out a higher voltage than this, but with a totally flat battery it may be dragging it down.

What size battery? a 70Ah battery will take 6 hours or so to charge fully. Leave it on overnight and see what kind of current it's putting in in the morning, it should have dropped to 1-2 amps if the battery has been taking charge.

If it is still taking a hefty charge in the morning, take the charger off and check the voltage across the cells, if it's down around

11-11.5v then you've lost a cell and the battery is scrap. If it's up around 12.5-13v or higher then it's charged ok. If the battery is not fully charged, then after replacement you should have the charging circuit checked as well, it may be that a charging fault has ruined the battery in the first place

Assuming you have a dynamo:

Fit it to the car, start up and hold at a high tickover, see what the voltage across the battery is, the regulator should be putting out about 13.5-14.8v. Higher readings above 15v indicate a fault with the regulator which needs adjusting (at best). If it is lower then you have a fault either with the dynamo, connections or regualtor. Check the wiring to the dynamo and the connections on the back of it, and also the connections on the regulator. clean and tighten them. Check the earth to the regualtor (if fitted) is present and has a good connection to the bodywork. If you are still not obtaining a suitable charging voltage, then your regualtor needs adjusting and/or replacement. The Workshop manual has the proecdure for this, but it is quite complex. If in doubt, find a good auto electrical place (NOT halfords).

If you have an alternator:

Have it checked out and replaced if necessary. Alternators do not have adjustment capabilities.

Alex

Reply to
Alex

In news: snipped-for-privacy@4ax.com, Alex blithered:

Checked the fan belt?

Reply to
GbH

Good point, however I tend to assume that such a simple item as this has been checked before someone shouts for help.

Alex

Reply to
Alex

I knew what you meant - what does that say about me :-)

Reply to
EMB

In message , Alex writes

It's often the simplest things that get overlooked, and of course every fault is simple once you've solved it. I always start with earth straps, battery - chassis - engine. IIRC dynamos had replaceable carbon brushes. Could be they need attention.

Also a decent battery will only need an hour or so charging to have enough in it to turn over your engine - if it's gone totally flat you've probably killed it anyway.

Reply to
hugh

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