Cold weather; Boosting a dead battery

[notfarnow]

-12F this morning (-32 with "windchill", for those who like scientific exaggeration)

My Jetta fired right up, but my Suzuki cranked over about 8 times before the battery went flat. I tried to boost the Suzuki off the Jetta, without the Jetta running, but it cranked over verrrrry slow. I didn't want to have a flat battery on the Jetta too, so I started it up again and boosted the Suzuki with the Jetta running. The Suzuki spun over much faster and fired up after a couple tries.

I was told to never start the "dead" car with the "good" car running… apparently it's hard on the "good" car's alternator. However, I do it anyway on occasion if I'm in a pinch…like this morning.

My questions:
-Anyone else do this?
-Is doing this actually hard on the alternator?
-If it is, do you think it's cumulative, or could I "toast" the alternator doing it once?
-Do most modern cars have some sort of load protection on the alternator?
-Is using fabric softener on my coveralls wimpy?

Now I need to figure why the Suzuki won't start. I think it's the starter, it seems to be turning over too slow. I used a starter from a sidekick automatic for the diesel swap, but it may not be up to the task. My battery is 750 CCA, which works fine in my Jetta diesel.

[Rot 911]

I always leave the other car running and have never has a charging or battery problem afterwards.

[john70t]

When the batteries are connected, the high-state-of-charge one starts draining amp into the low-state one.
Then the alternator's voltage regulator(internal on new cars) senses the drop in voltage, and "full fields" the windings in order to increase amps output and return the good battery to a fully charged state. It can overload those circuits which are designed for a normal 5-20 amp flow and damage the unit.

Time to switch to a synthetic or a lighter-weight oil in the Jetta for the winter which won't turn into jello as easily.

The battery should be taken out and slow charged(2amp), and then re-tested. Lead-acid batteries can't be fully discharged (m)any times before they become recycle material.

[Joeaksa]

Like John said, lighter oil and a totally charged battery. Again agree on the slow charging overnight or even for a couple of days. Charging at a higher rate can overheat the plates inside, warping them and destroying the battery.

If the battery does this again then pull it out and have it tested.

How old is it and any chance that its getting time to be replaced?

[notfarnow]

To clarify, the battery in the Jetta is A-1. The car starts easily, even with 15w40.

It's the suzuki w/diesel engine that's giving me grief. Battery is about 3 years old. It came with the 1.6TD engine from a 92 Jetta diesel, and started it no problem last winter. It sat unused for about 4 months, but had a good charge the whole time. I'll try hooking it up to a charger to see if it starts better. I don't mind buying a new battery, if that's what I need. Only problem is size, it's original 1.3 gas engine only needed a dear little battery to spin it. I'll need to hack & hew to make room for a larger battery.

I'm not too keen to go with a lighter oil, I drive the thing pretty hard and it's doing 3400 rmps on the highway. I've always been able to start diesels with 15w40 as long as I had a good starter & battery and 4 good glow plugs.

[Joeaksa]

How about getting a battery minder and plugging it onto the battery when you get home or putting a timer on it and having it come on at 0400 in the morning for a few hours before starting it?

Sure sounds like you need a bigger battery there. Have you compared battery sizes between the engine that came in the car and the one in the car now? Diesels take a lot larger battery in many cases.

[notfarnow]

Thanks Joe!

Originally posted by Joeaksa
How about getting a battery minder and plugging it onto the battery when you get home or putting a timer on it and having it come on at 0400 in the morning for a few hours before starting it?

I have a block heater & battery warmer for it, but I didn't use them last night, and I left it outside in the wind. My Jetta sat alone in the garage. I didn't want to have it fire up fine in teh warm garage, only to leave me stranded after work (I park outside). I'd just as soon deal with the issue in my driveway. This was the first real cold snap since I put the diesel in, so I'm trying to work the bugs out. I want it to start in -30 without shenanigans.

Originally posted by Joeaksa
Sure sounds like you need a bigger battery there. Have you compared battery sizes between the engine that came in the car and the one in the car now? Diesels take a lot larger battery in many cases.

Well, this is the battery that started this engine last year winter... I took the battery & engine from the same car. Mind you, it could be past its prime. It has 750CCA, which is usually sufficient. Mind you, I have an ATV plow that uses an electric winch, so a 1000CCA battery would be nice if I could get it to fit.

[legion]

Originally posted by Joeaksa
How about getting a battery minder and plugging it onto the battery when you get home or putting a timer on it and having it come on at 0400 in the morning for a few hours before starting it?

+1

I have my 951 on a battery minder in the winter. I bought it at Interstate Batteries for $50. It reads the voltage on the battery and only charges it as needed--it's not a trickle charger (have one of those too) that charges a little no matter what. It also came with a little harness so that you can wire it to the battery/ground and just plug the car in rather than using the clips around the battery posts. The 951 starts up right away when I take it out in the spring after 4+ months of storage.

[mattdavis11]

Swap the batteries, see what you get. Jumping a diesel is not a good idea. Negative lead last on the dead car. Vapors can kill you.

[notfarnow]

I've been thinking of getting a battery minder for my sailboat's 2 batteries. My concern with using it on the car or the suzuki is that it will mask a problem. It'll start great in the morning, but then be dead as a doornail after work.

I didn't even use the block heater on the Jetta last night... I wanted to make sure it would start dead cold with no help. It did, so I know I won't be left stranded. Now I'll use the block heater to make life easier on the starter & engine. I'll do the same with the Suzuki once I get it starting well in the cold.

[notfarnow]

Originally posted by mattdavis11
Swap the batteries, see what you get.

Will try that after work

Originally posted by mattdavis11

Jumping a diesel is not a good idea.

Why's that? I've heard that you need REALLY heavy cables, which I have.

[mattdavis11]

Batteries on a sailboat? I've heard it all now.

[legion]

BTW, this thread illustrates exactly why I sold my 300D.

[notfarnow]

Originally posted by mattdavis11
Batteries on a sailboat? I've heard it all now.

I know. I got bursitis in my shoulder a few years ago, and couldn't start the outboard without hurting myself badly. Got an electric start. Sweet!

Having a second battery allows me to run all the lights & accessories without having to worry about starting it.

[mattdavis11]

Originally posted by notfarnow
I know. I got bursitis in my shoulder a few years ago, and couldn't start the outboard without hurting myself badly. Got an electric start. Sweet!

Having a second battery allows me to run all the lights & accessories without having to worry about starting it.

Hate to hear about the bursitis. I wish you well.

Wind and sunlight should provide all the necessities to operate a sailboat, raft, or what have you.....

Is it really a sailboat?

[notfarnow]

Originally posted by mattdavis11
Hate to hear about the bursitis. I wish you well.

Wind and sunlight should provide all the necessities to operate a sailboat, raft, or what have you.....

Is it really a sailboat?

Ya, I got away without a battery for daysailing. Having a battery allows us to do weekend adventures up the river. Otheriwise you have to get home before dark. Sailing under a full moon is hard to beat, and you can't do that (legally) w/o lights. Plus, underwater lights & skinny dipping are a plus.

As for the Suzuki, I'm worried about going with a lighter oil. I tend to beat it pretty hard, and it's doing 3400 rpms @ 65 mph. I get 1200* EGT and 12 lbs of boost regularly. I'm afraid I'll kill it if I run 10w30. I'd rather try different starters before going to a lighter oil.

[mattdavis11]

What's a better starter going to do? Kill the top end first? Get a heater to keep the oil warm.

[notfarnow]

i yi yi

It's cold out there!

Tred swappig batteries but it still wouldn't start. Then tried with both hooked up, still no-go. Pluggd in th block heater for 30 minuts and just got it strted. Warming my hands and feet by teh fire.

Startr is NFG... not spinnig it fast enough. Will try 10w30 but will probably have to get a new startr . Wonder if Grand Vitara v6 starters are bolt in upgrads

[Joeaksa]

Jake,

Just wonder if you have a starter that is dragging? Have seen it happen and that saps the amps right away before even turning the engine over.

If the block heater works you might think about the thinner oil...

[notfarnow]

Originally posted by mattdavis11
What's a better starter going to do? Kill the top end first? Get a heater to keep the oil warm.

I have a block heater that I will use once I get this stuff sorted out. I take it to work once or twice a week, and it sits outside for 9 hours, so I need it to start reliably in the cold.

Originally posted by Joaska
Just wonder if you have a starter that is dragging? Have seen it happen and that saps the amps right away before even turning the engine over.

Joe, I think that's what's going on... starter is no good. Did some digging online and I think I have the wrong starter in it. Some places list the sidekick starters as the same for auto & manual.

Manual:


Auto:


Mine looks like the manual one, so I'm going to see if I can't track down an automatic one before the weekend.


Thanks for the advice folks!