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Battery terminals caked in yellow

Discussion in 'Technical and Troubleshooting Torque' at netrider.net.au started by Riderman, May 31, 2011.

  1. I inspected my battery few weeks ago and found the temrinals covered in hard yellow residue. I cleaned it off.

    Last weekend I inspected it again and found more yellow caked residue over the terminals.

    Is this a sign to replace battery? or could something else have caused this?


  2. Probably the same thing you see on cars, just a bit of corrosion. Clean it up, coat the terminals with a little oil or grease. There is a special stuff for coating terminals which is like shellac or lacquer, and it lasts longer between cleans, but it costs a bit and it's not really worth getting for just one vehicle. It does seem to happen more as the battery nears the end of its life, but its not a sign in itself that the battery's no good.
  3. Thanks for the quick reply.
    I just wanted to confirm with someone.

    Ill look into the coatings!
  4. My dad used to recommend petroleum jelly, seems to work - nice and cheap.
  5. Yep, WD40 also works for a few months.
  6. Thats the sulphur depositing from the sulphuric acid in solution.
  7. If it is white and/or green, it is a little corrosion from battery acid misting out of the battery. Which means that the battery is getting toward end of life. A little misting isn't so bad, but keep an eye on it. A battery in good condition, with a proper charging voltage on the bike shouldn't do it, so it can mean that the voltage regulator isn't working too well either.

    If it is yellow it is sulphur deposits from evaporating battery acid. Which means that the acid level in the battery is dropping. Which means that the battery has less capacity, and will get hotter when being charged. Which means that it will evaporate more acid than previously.

    If the battery is the maintenance free sealed type, it shouldn't be doing either of the above, although they can vent a bit if they get very hot or overcharged.

    If you can and do top up the battery with distilled water to avoid the overheating and make sure the plates remain covered, the acid is diluted and so you lose capacity. From there it is a downward spiral to eventually being stuck with a bike that won't start.

    So, keep an eye on it and be prepared to replace it soon. If you want to extend the life a little, a good smart charger can help do that. There was a thread on chargers recently, here: https://netrider.net.au/forums/showthread.php?t=121395&highlight=smart+charger
  8. RoderickGI , awesome reply - thank you.

    The battery is a 'maintenance free' one.

    From your explanation, I think i have an answer -
    My bike had to go in for factory recall (known rectifier issue), it was resolved easily by Suzuki, so I think it may be due to that. That is when I cleaned it off (before I took it in), and now everything is running fine, the sulphite has returned.

    I think a new battery may be the way to go to be sure.

    Just curious, I know it's been cold these days but I find I almost always have to give the throttle 1/8 at crank to start it, otherwise it won't start. Is this a cold/temp related issue or battery weakness (or both?).

    Bike is a 09 gsxr, so it's pretty new.
  9. Any fuel injected bike should automatically handle it's own choke.
    If you have to manually crank the throttle to actually start it, you are effectively shoving more fuel into it and that's a sign of a larger problem.
    Like a leak in the air intake so it's drawing more air than it should and running lean.
    Get that checked.
  10. But in the manual it advises to twist throttle a bit on cold starts? I know what you mean though...

    Any comments people?
  11. Glad the jelly works for your Dad but does it work on batterys?
  12. Since it is a maintenance free battery, and the bike had a rectifier problem, I would be replacing the battery. Rectifier problems can mean low voltage, which results in the battery not charging, and is therefore discharged too much and permanently damaged. They can also mean overvoltage, and hence over charging of the battery, boiling the acid, and hence leaks or at least fuming of the acid, and possibly permanent damage. Usually rectifier problems mean both under and over voltage during the failure cycle, so you get both problems.

    You may just want to check the voltage at the battery terminals when the bike is running to be sure the new rectifier is okay. Measure at cold start and through to warm. It wouldn't hurt to check the battery voltage before starting after it has been sitting a while as well, to see that it is holding charge.

    But yeah, new battery time.

    As Mountaineer says you shouldn't have to use throttle to start a fuel injected bike, but . . . on very cold days or when it has been sitting for a while my Ducati likes just a little throttle momentarily to get the juices flowing. I just take up the slack in the cable for a moment though. No where near 1/8th of a turn. In fact I couldn't do that, because my bike has fancy electronics that only require me to push the button once, then wait for it to start. It keeps cranking until it starts or times out. I usually only crack the throttle if the first attempt doesn't work. If I actually opened the throttle any more the electronics stop trying to add choke and it won't start. Too smart for its own good!

    If your bike manual says to use a little throttle on cold days, I guess it is fine to do so.

    However, just about all fuel injected bikes will start easier if the battery is fresh. I guess the higher voltage means that the fuel pump gets up to and maintains pressure faster and easier, the engine turns over faster and sucks in more fuel, and the spark is stronger. That is just another reason to connect a smart charger to the bike battery if the bike isn't going to be used for a while.

    You are a bad man Grey.
  13. RoderickGI, you are a legend.

    Thanks for that reply.

    I think you're right on all counts. I'll look into it on the weekend. Could explain the cranking issue too.