Steaming battery: diagnosis help needed

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CraigRegs

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So here's the background: Late last summer, the bike was cranking slowly, even failed to start a couple of times, but popped off with a push-start. 3-year-old battery, so I replaced the battery in September (WestCo AGM).

Didn't seem to fully solve the issue, as the bike still cranked kinda slow. So after stepping through the diagnosis in the FSM, R/R was replaced in November.

Through the winter, the bike cranked slowly, but almost always started, even when sitting in low double digits throughout the day. Several times, though, only a couple of attempts to start it would drain the battery.

Last week, I'm prepping the bike for sale, and had the tank and airbox off, ECU unplugged. After reassembly, it again wouldn't catch and start before draining the battery. After three or four charges from the Battery Tender, I decided to jump it with my truck. Again, it didn't pop right off, but after sitting on the cables for a good 10 minutes, I could get it to turn over at the normal speed. Had to hold the starter button for 3-5 seconds 4 times before it finally started. (I'm thinking that was needed just to get fuel through the fuel line.) Over the next 3 days, the bike cranked at normal speed, and started fine. After my first ride I smelled something hot, but dismissed it as tar on the pipes or something. Third day, I'm out for a 2-hour cruise, and upon returning to town can again smell that smell (not the Skynyrd one, thank goodness). In the garage, I track it down to the battery compartment, and when I pull off the panel, here's the little Old Faithful that greeted me:

a2326af1-8868-423a-90a2-495eed3245b0_zpsorgufxly.jpg


That's a column of steam from the vent hole to the left of the battery holddown. Let the bike cool several hours, and tried starting it. No luck, so now I can't get the bike started so I can test the R/R and stator, and I'm hesitant to jump it until perhaps some of you can answer some questions. Such as:

  • Is the R/R likely bad and allowed the battery to overcharge?
  • Have I fried the battery?
  • Have I fried the R/R?
  • Did jumping it from the truck precipitate this?
  • If so, what else might I have damaged?
  • Or is it the stator or something else?
Any help appreciated.

 
First thing to check is the charging voltage. If the voltage across the battery with the engine running at 2500rpm is over 15V, then the regulator is fried.

If that checks out (14.2-14.5V is good), then remove the battery and have it load-tested. Walmart will do that for you, Autozone too.

If the battery tests bad, replace it and the next check would be cranking speed. If that is not normal (slow) then start to suspect the starter motor.

Cranking amps should be around 80-90, bad starters can attempt to pull 200 amps from a battery that can't deliver it, and it will get hot.

If you jump started the bike with the truck engine running, there is a very good chance you fried the regulator.

Let us know how you get on, and others may suggest other, quite simple checks that I forgot.

 
ps .... Are you sure that "steam" is coming from the battery, and not from a coolant leak hitting the headers?

 
Is it steam or wires melting. Your nose should be able to tell. Rubber or metallic acid.

Dave

 
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That looks like too much steam/smoke for the battery. I thought AGM batteries were sealed, anyway, so they won't steam. Was the bike run long enough to be warm enough for steam from the antifreeze if it was leaking? Antifreeze steam smells slightly sweet, very different from hot electrical parts.

Did you just wash the bike or otherwise get water in there that might be steaming off?

 
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As said, coolant and plastic insulation both have distinct, different odors. I think burning/melting wire insulation has a much more noticeable scent, but both are pretty pungent.

A boiling battery would have a very different smell, I expect, but I don't recall ever having had the opportunity or misfortune to experience one. If it is coming from the battery, be careful and take extra safety precautions. Capture a bit of the moisture on a paper towel before attempting to whiff it

My money is on a coolant leak, and the starting problems may be coincidental/unrelated.

 
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Put your voltmeter across battery and read while cranking. If voltage is above 9.5 there is enough voltage for the ignition system to work and start the bike. Less than 9.5volts while cranking you have a problem which may be a starter or a bad battery.

Also may have an issue with RR, as others have suggested, if you can get it started' check charging voltage, have battery charged and tested first.

 
Thanks for the replies. Steam was definitely emanating from the battery. You can see a small puddle of fluid around the vent hole. Not a sweet anti-freeze smell; more of a petroleum/metallic smell. Twigg, John, all good advice. Hope to be able to follow up in the coming days.

 
Pull the battery and do something to neutralize the acidic condensate from that battery steam. Baking soda/ watermix will help keep the surrounding area from being damaged from the acid. The next owner will appreciate it.

Good luck with the tests, hopefully it will be something cheap and easy. Heed the good advice given in the above posts, and let us know the outcome.

Brodie

:)

 
Yep. Get that acid neutralized.

Cranking a bike from a car can cause more problems than it solves if you're not careful. Always do it from a car with the engine off so it's charging system isn't pushing the bike's system beyond it's design limits.

 
I have had a battery on a 5 ton truck blow up in my face from a starter that was suck in the crank position and was drawing way too much current. Luckily, I was wearing safety gear appropriate for battery work.

Sealed batteries are only relatively sealed. They have valves that open if there is a dangerous build up of pressure, which is what is happening here.

I am going to go out on a limb and say replace your starter.

 
+1 on the starter. I suspect it is cooked. R/R may be bad as well - easy voltage check. You may have toasted the battery by this point as well.

 
My vote would be the new R/R you put in.

You need to measure what the charging voltage is across the battery when the engine is running. It should be close to 14.2V at idle and should not increase when revved up to higher rpm. If it is considerably higher it will boil the electrolyte and cause it to steam.

Jumping the battery off a car battery will not screw up the battery (since it is only 12.8V) but it may have damaged your R/R.

 
+1 on the starter. I suspect it is cooked. R/R may be bad as well - easy voltage check. You may have toasted the battery by this point as well.
But before you do that, because they are expensive, check the grounds.

 
I would be wearing safety goggles at a minimum, a full face shield would be better and some heavy rubber gloves before I started working around that battery again. Definitely remove it from the bike and place in a safe place where it won't cause a lot of damage if something should go wrong. Then take care of neutralizing the entire area around the battery mount with a water/bicarbonate of soda (baking soda) paste and strong solution followed by a thorough flushing.

 
If the bike battery was at a low charge when you connected the auto battery you may have dumped too much current too rapidly into the bike battery.

When charging a bike battery the charging current should not exceed 3 amps. On my battery's label the maximum recommended current is 1.2 amps, 10% of the 12 AmpHour rating.

When charging current exceeds the recommended maximum the battery may overheat causing the electrolyte solution to bubble creating hydrogen gas.

 
Decided to pull the battery tonight to take it for testing as Twigg suggested. After getting the cables and the holddown strap off, I noticed the battery seemed to be rather...oddly shaped:

IMG_1476_zps1cpx2do7.jpg


IMG_1475_zpsiyvuqhzy.jpg


Yep, it got PLENTY hot. The pics don't quite convey the amount of bulge on the casing. I think I'm extremely lucky that this didn't grenade.

So, I must have fried the R/R when I jumped the bike with an idling pickup truck.
fool.gif
Fried R/R means all kinds of electrons dumped into the battery and they couldn't get out.

Plan of action:

  • New R/R ordered
  • I have a spare battery on the shelf that tested good, so that will go in
  • Researching starter replacement to see if it's a job I want to tackle, because I think that's what's at the root of all this as Twigg and other suggested.
Anyone with experience replacing the starter want to offer any tips/caveats/warnings?

 
Before you fit that new regulator, pop the good battery in, start the bike and measure the voltage across the terminals. If the voltage is around 14.5V you didn't harm the regulator and don't need a new one. Very high probability it is damaged though, because regular charging could not do THAT to a battery and it was probably getting around 20V for quite a while to bulge like that. Kudos to the makers for a very tough casing!

You won't hurt the newer battery if it is well-charged and you limit the running to a few minutes. It might save you the cost of a RR.

I spent quite a bit of time on the Yamaha Triples Forum. It always surprised me how few of the guys didn't understand why you shouldn't jump a bike with a stator, with the car engine running ... and how expensive it could get if you did :) Generally the RRs survive the ordeal, but a big truck alternator produces a lot of power, which arrives at the bike with, as you say, nowhere to go except very bad places!

 
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