Battery woes

wattfield said:

1. 13.2v at the battery
2. Checked a few times - 9.3 - 9.8v.
3. It's dark, I might try this at the weekend.

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13.2 V sounds a little low. I'd be inclined to load the system down (headlights, heaters etc.) and see how low it does drop.

I tested our Freelander's alt and it put out 14.4 V straight after starting, and didn't drop below 14 V even under heavy loads.

Alternatively, your cables could be corroded and causing voltage drop (had this on the FL, hence the test). See if you can test right at the alt too.

13.2 simply isnt enough, especially at this time of year.
You can reliably get an a127 to make 14.2/3 volts all day long if you fit a tractor brush box (ebay 10 quid) to the alt and extent the sensing wire back to the battery and fit a resistor in the wire, both my tdis run this and it works well.

First time I've had the chance to look at it in daylight, I cleaned up the alternator contacts & earths & tightened the belt, now getting over 14 volts even with the lights & heater on.
I'll drop into Halfrauds for a free battery test tomorrow.

14 volts is good, you might find the battery still needs a charge as an alt can never get the battery back to 100 percent once its been flat.
The cheap cig light volt gauges from ebay really are a good investment, Ive got one in all my cars/machines a quick glance lets you know if you have potential problems.

http://www.ebay.co.uk/itm/LED-Car-B...686146?hash=item4657ad4dc2:g:IFsAAOSwu4BVh-F9

My 300TDi 90 runs a Mercedes 600 048 076 (760A / 100AH) which I fitted in Aug 2005, think that is pretty good!

Prior to that I was running an Exide Maxima but that expired after 2-years & 2-Weeks, the 2-weeks being the critical part as it was then out of warranty. No prior warning, no loss of performance, just dead.

After that decided to go for a traditional type and got a good deal on the Mercedes item from a local dealer, case of needs must and I haven't been disappointed.

I've got a battery from performancebatteries.co.uk its a CTI1000, the same size as a 644 but is a 1000CCA, its a no maintenance one with 4 yrs warranty , I've got 2 on my tractors and both are over 5 yrs old.

I had the battery tested and they reckoned it was at 50% of cranking amps. They also got under 13v from the alternator, so suggested the battery might be OK but the alternator could be the problem, but as I had 14v from the alternator they suggested it could be a worn belt getting loose, although I tightened it up the other day. I came home & charged the battery, it got to full charge in 15 minutes. My round trip to work is a varied 35 miles, lights, heater & radio on all the way. It started fine this morning, but it wasn't as cold as when I've had trouble before.
I would have thought that a battery with a decent charge in it with 50% of it's supposed CCA would need replaced, even if it wasn't getting a full charge from the alternator the whole time. Am I right?

Oh yes, and I'd like to know tonight so I can cancel my order for the battery - or not!

Ta!

wattfield said:

Oh yes, and I'd like to know tonight so I can cancel my order for the battery - or not!

Ta!

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Bit late for me I am afraid!

But I would get another. They dont last for ever. You can go on for a while topping up, putting a charger on overnight, messing around. When you get tired of it, you get another.

Horses for courses really. I dont worry too much, with five vehicles in the yard, I just take another or jump it. If it was my sole motor, and I had to go to work, I would get another.

wattfield said:

I had the battery tested and they reckoned it was at 50% of cranking amps. They also got under 13v from the alternator, so suggested the battery might be OK but the alternator could be the problem, but as I had 14v from the alternator they suggested it could be a worn belt getting loose, although I tightened it up the other day. I came home & charged the battery, it got to full charge in 15 minutes. My round trip to work is a varied 35 miles, lights, heater & radio on all the way. It started fine this morning, but it wasn't as cold as when I've had trouble before.
I would have thought that a battery with a decent charge in it with 50% of it's supposed CCA would need replaced, even if it wasn't getting a full charge from the alternator the whole time. Am I right?

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I'll call in @Joe_H for you from the Freelander section - he's the last word on battery/electrical stuff.

50% CCA suggests the battery has lost some of its ability to deliver current, but did they not tell you how much charge capacity (Ah) was left? That would be good to know.

The alternator results are odd - maybe someone's meter isn't accurate, or there really is an intermittent fault with your alternator/cables. The results may depend on where the alt output was measured, and whether the cables/straps linking alt to battery are sound. Test right at the alt and also at the battery under heavy load and see if there's a drop.

I had an internally corroded earth strap on the Freelander that was giving intermittent no-cranks and spuriously low alternator charge voltages. Until I did ground-ground voltage drop tests under cranking and charging, and found the problem, I was ready to replace battery, alternator and starter!

My battery has arrived, and because the one I ordered was out of stock they've sent me an "upgrade".. Hankook MF31-1000 - 130 Ah, 1000CCA.

wattfield said:

My battery has arrived, and because the one I ordered was out of stock they've sent me an "upgrade".. Hankook MF31-1000 - 130 Ah, 1000CCA.

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Proper job. That will do nicely.

Not being nosey, but about how much? Reason I ask is we need similar for the starter battery in the boat.

Turboman said:

Proper job. That will do nicely.

Not being nosey, but about how much? Reason I ask is we need similar for the starter battery in the boat.

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Here you go... https://www.batterymegastore.co.uk/hankook-mf31-1000.html

wattfield said:

Here you go... https://www.batterymegastore.co.uk/hankook-mf31-1000.html

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Thats not bad at all. Think I paid about £90 for the one I got for my tractor in the spring, but I had to go to the wholesaler up Truro.

That's a very good price. 4 year warranty anorl!