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A battery question

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T

Tinster

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My new battery has a buildup of white crud around the
+terminal after about a week of auto use. Is this normal?
Or caused due to the salt air environment?

I wipe it off whenever I see it.

I no longer unhook my battery every time I shut off the car.


thanks

PS: a funny- met a lady while driving Amos. She told me
about this club that has a few Triumphs. Told me there
was a guy used to have a TR6 that looked a little bit
like mine ! I bit my tongue and did not say a word!!

d
 
Hey - you're supposed to be out buying groceries!

The white powder is pretty normal, altho' I "prevent" it by spraying battery terminal protectant on the terminals. We've talked about this in many threads here before.

Tom
 
A little buildup on the terminal over time is normal. But to be safe, I'd check to make sure your alternator is not overcharging the battery. You should see, I think, around 13.2 volts when the engine is running. If you start seeing up around 15v or more, you've got a bit of a problem.
 
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If it appeared that fast, I'd check the charging voltage sooner rather than later. With a fully charged battery and the alternator cool, the voltage should be between 13.6 and 14.4 (according to Lucas).

Don't forget that white powder is poison (lead sulphate), so treat it with some respect. Try not to breathe the dust, wash your hands afterwards, that sort of thing.
 
One item that helped me was to buy a quick twist disconnect. You see them on Ebay all the time for a couple of bucks. But I think the last 2 posts may be right. Something is going on for it to happen this quickly.
 
Dale, you can get the treated felt anti corrosion washers for the battery posts that help quite a bit. If you can't get them on the island, let me know and I'll send you a set.
These, coupled with the anti-corrosion spray, eliminated the problem for me. My alternator puts out 14.2 volts, incidentally.
Jeff
 
It's quite possible that there is a mild leak at the base of the positive terminal, and a small amount of acid is getting past the case. It's not an uncommon fault to see even in newer batteries. Sometines the lead terminal dosen't get sealed to the plastic very well. and when the acid hits the air it corrodes the terminal. Vasiline would help. keep an eye on the seam where the terminal sticks out and see if it looks wet. Also like was mentioned, set your voltmeter to a 20V setting, then with the engine running put your test leads on the battery terminals (red to pos, black to neg) and see what your voltage is. 13.2-14.8 (roughly)is normal. If it's over 15v that's too much..
Make sure you bring the RPMs up during the test to simulate cruising speeds.
I'm betting it's just the batery it's self. No biggie.
 
Yep, I also use a fine film of Vaseline and I've never had that problem. Bone dry terminals will get a white oxide fairly quickly.
Regards
Craig
 
14. 6 volts measured at the battery terminals
with engine warm and at about 2000 rpms.

It seems a dry terminal might be the culprit
I cleaned it up and covered it with electric grease.

We'll what happens.

d
 
14.6 is kind of high, especially if the alternator was warm. No doubt some grease or anti-corrosion will save the battery clamps, but overcharging will shorten the life of the battery. The white powder is caused by electrolyte being ejected from the battery.

If you are sure your voltmeter is accurate, I'd go looking for the problem. If the regulator is seeing the full 14.6v, you may need a new one. But it could be a bad connection lowering the voltage to the regulator.

If you do decide to live with it, keep a careful eye on the steel in the vicinity as well, especially under the battery. Battery acid has a habit of creeping under paint.
 
Randall,

The volt meter reads 12.6 between the battery terminals
with the engine off and cold.

The GM alternator is new, the wire harness is new
(Dan Master Power Block) and i'm not sure I have a
voltage regulator. If I do have one, where is it located?

thanks,

dale
 
TR3driver said:
14.6 is kind of high, especially if the alternator was warm.
Click to expand...

14.6 volts is the setpoint for a 10SI voltage regulator. That would occur with a nominal load of about 10-15 amps. That is the setpoint for most alternator regulators today.
 
Tinster said:
The GM alternator is new,
Click to expand...
My apologies, thought you still had a Lucas. Art is quite right, 14.6 is within normal for the GM.
 
One other item. When you do install the battery terminal cable ends. It's a good idea to open them up so that they slide to the bottom of the post easily. Then tighten them and coat all, I say again ALL exposed metal with a good petroleum type grease.
 
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