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EA81T overheating battery cable


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Hey guys -

 

I'm trying to fire up an EA81T with a fuel delivery problem (I know what it is, I'm applying a fix that I'm hoping will avoid having to replace unnecessary parts). However, I'm having a secondary problem.

 

The positive battery cable is overheating. Like to the point it is starting to melt its sheathing.

 

Ideas as to what could be wrong? Batt is new, everything else is an unknown.

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Anywhere specifically I would need to add one?

 

 

An extra, thick cable from the engine, any part, to the frame, any part will be sufficient. I put one from the backcorner of mine to the sturt tower cross brace/spare tire holder bolt hole.

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An extra, thick cable from the engine, any part, to the frame, any part will be sufficient. I put one from the backcorner of mine to the sturt tower cross brace/spare tire holder bolt hole.

 

Cables aren't a problem, I have a disassembled ground kit for a Civic laying around.

 

From the engine to the frame? ok, easy enough.

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I'd also get your alt tested, as the others have suggested, and if you're running heavy duty lights or an amp and speakers, i'd maybe upgrade your power wire too, it couldn't hurt.

 

Will do on the alt on Tues when I have time to work on it again.

 

Car's bone dead stock, stock AM/FM cassette, doesn't even have the factory optional fog lights, so current draw shouldn't be a problem.

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Cranking it a LOT could overheat the cable to the starter... is that what you are refering to... or the smaller line going to the fusible links?

 

I've also seen positive cables get hot when they were damaged - sometimes it's hard to tell. Look close at the cable end for the battery. If there isn't a good connection they will get hot.

 

Wouldn't think this would be the alternator if the engine isn't running. Unless the engine is getting up to 800 RPM or so the alt won't put out much.

 

GD

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Cranking it a LOT could overheat the cable to the starter... is that what you are refering to... or the smaller line going to the fusible links?

 

I've also seen positive cables get hot when they were damaged - sometimes it's hard to tell. Look close at the cable end for the battery. If there isn't a good connection they will get hot.

 

Wouldn't think this would be the alternator if the engine isn't running. Unless the engine is getting up to 800 RPM or so the alt won't put out much.

 

GD

 

Actually, this happened after cranking it for just a few seconds with the car completely cold. And it's both wires that get hot... the starter wire and the smaller one.

 

I at first attributed the smell to the fact that the car's been sitting for a while, because Freebie still smells like burning garbage every time I turn it on... and I've run THAT engine for a few hours since resurrecting it.

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If you suspect the alternator just disconnect it. Engine will run fine without it for a while. Might be putting out high voltage, but I would think your issue is with cranking it for too long. A few seconds? More than 15 or 20? You should wait 1 minute for every 20 seconds of cranking.

 

If both of those wires get hot then it's your starter... well cranking. The ignition switch runs full current through to the starter solenoid, so there is a LOT of draw going on. Those gear reduction starters can pull 600 amps easy.

 

GD

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You are looking at a bad connection. You might have corroded wires where the terminal is. Bad connection=resistance=heat Your alternator is not in the equasion.

 

You are probably cranking your engine a lot and I suspect it is barely cranking enough to get the engine started. If your starter has bad bushings it will draw more current from the battery to start the engine but the cable should be able to handle it without any problem whatsoever. It's a cheap fix to replace the cable.

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GD - actually, the sheathing of the cable started smoking after about 5 seconds of cranking, with everything stone cold. Again, I initially ignored it because I thought it was just detritus under the hood burning up. Turns out it was the cable.

 

Boosted - How fast are these starters supposed to turn? I've never had an automatic on an EA series, so I have no frame of reference. However, compared to the starter on a manual, it turns slowly. maybe 1/3 to 1/2 as fast. Would that be what you're referring to?

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Sounds like it might be a bad connection at the positive battery terminal overheating, and transferring heat up the wire to both of the positive wires? The starter draws alot of current, but I have moved subarus with the starter without melting insulation, so it shouldn't be a problem. Unless... the EA82 I did that with has a good #2 or 1/0 sized wire going to the starter, but I think someone said the EA81 doesn't have as big of one?

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Sounds like it might be a bad connection at the positive battery terminal overheating, and transferring heat up the wire to both of the positive wires? The starter draws alot of current, but I have moved subarus with the starter without melting insulation, so it shouldn't be a problem. Unless... the EA82 I did that with has a good #2 or 1/0 sized wire going to the starter, but I think someone said the EA81 doesn't have as big of one?

 

Actually, that is also a possibility. The cable WAS only room temperature down by the starter, but really hot by the battery connector.

 

So this is another vote for replace the battery cable?

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Actually, that is also a possibility. The cable WAS only room temperature down by the starter, but really hot by the battery connector.

 

So this is another vote for replace the battery cable?

 

Not exactly -- it's probably the connection that's generating the heat. If you can replace the battery terminal on the end of it, the cable might be fine. Problem is that usually the old cable is so dirty you can't get a decent solder connection on the new terminal without chopping a few inches off, and then it's too short....

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The turbo engine should crank faster than the n/a model due to lower compression. I'm not sure about the auto - manual differences, I would assume the same.

 

Your first order of business is to replace your battery cable. Right now it is acting like a giant resister that isn't letting your starter get the full 12v therefore it won't crank very fast which means you probably have to crank longer. Which makes the matter worse, a catch 20.

 

Once you have clean terminals and a good battery cable, I guarantee it won't heat up like it did, regardless of your starter's condition. And it should crank faster and your engine will probably start quicker.

 

Just for s&g's you could take a voltage reading at the positive terminal of the starter while cranking and compare it to the battery POST while cranking and you could see how much voltage your cable is throwing away.

 

 

GD - actually, the sheathing of the cable started smoking after about 5 seconds of cranking, with everything stone cold. Again, I initially ignored it because I thought it was just detritus under the hood burning up. Turns out it was the cable.

 

Boosted - How fast are these starters supposed to turn? I've never had an automatic on an EA series, so I have no frame of reference. However, compared to the starter on a manual, it turns slowly. maybe 1/3 to 1/2 as fast. Would that be what you're referring to?

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OK, here's a possible long shot, but check it out anyways.

One of my cars had aluminum wire for the battery cables. One day the car wouldn't start - turned out it was a little corrosion in the batt. terminal. Corroded aluminum = aluminum oxide = insulator. So, what I'm getting at is that if your wires are aluminum, you could have poor contact, causing the current to not flow though all of the strands of the wire, which would definitely cause melting of insulation.

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