Battery Questions
07-21-2014, 09:36 AM
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Battery Questions
Does the car get it's electricity from the alternator or the battery? I think the battery.
Will the car fail to run if the battery is flat? Even if it is jumped to start. I think answer to this is yes too.
So if I answered my questions correctly then Why will the car not run on the alternator. I think a car with a generator will run on the generator. It's been a long time since I had my old Bugs, but I think that was the case.
So ultimate question is how large of a battery does one need for 993? I'm thinking Odessy, I have one in my 2012 4runner and it so far always works even if vehicle has sat 2 week or more.
Will the car fail to run if the battery is flat? Even if it is jumped to start. I think answer to this is yes too.
So if I answered my questions correctly then Why will the car not run on the alternator. I think a car with a generator will run on the generator. It's been a long time since I had my old Bugs, but I think that was the case.
So ultimate question is how large of a battery does one need for 993? I'm thinking Odessy, I have one in my 2012 4runner and it so far always works even if vehicle has sat 2 week or more.
07-21-2014, 09:37 AM
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Buy an Interstate MTP-91.
07-21-2014, 09:45 AM
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Ron, I just bought an MTP-91 from the Interstate dealer off Rivers Avenue. Technically they are discontinued, but they have some still in stock. Perfect fit. Don't forget to buy the vent kit.
07-21-2014, 10:32 AM
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On other vehicles and a boat I use Odessy PC 1500 and Sears Maine Platimum 34m batteries. I tried t fit the Sears battery in my 993 and it will not fit, need to see if rennline sells a mounting kit that will work. I put that Sears on right up with the Odessy
07-21-2014, 10:49 AM
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Does the car get it's electricity from the alternator or the battery?
I believe the battery to start and alternator once running, however the battery acts like a voltage stablizer. spike smoother as the voltage from the alternator can fluctuate and is full of electrical noise and the voltage regulator can take a moment to adjust the alternators output when a high draw item is switched on like the A/C. The noise probably will interfere with the ignition computer's ability to function properly. Keep in mind that ultimately the alternator has to generate enough current to sustain the entire electrical load of the car's system while running at all times otherwise you battery would go dead over time.
Will the car fail to run if the battery is flat? Even if it is jumped to start. I think answer to this is yes too.
I don't know but it is probably very hard on the electronics if you attempt this as jumping a car produces huge spikes and electrical noise in the process.
So if I answered my questions correctly then Why will the car not run on the alternator.
Probably because of the electrical noise present.
So ultimate question is how large of a battery does one need for 993?
Large enough so that when the current drawn by engaging the starter does not drop the voltage on the system below the point where the ignition computer and system fails to cause ignition. With an inexpensive meter my battery at rest provides 12.5 volts, initiating the starter it drops to 10 volts and once the engine starts it sits between 13.9 and 14.2 at first. Turning a major eletrical load on such as the headlights or the A/C causes the number to drop 1/10th of a volt.
Hope my experience and opinions help here,
Andy
I believe the battery to start and alternator once running, however the battery acts like a voltage stablizer. spike smoother as the voltage from the alternator can fluctuate and is full of electrical noise and the voltage regulator can take a moment to adjust the alternators output when a high draw item is switched on like the A/C. The noise probably will interfere with the ignition computer's ability to function properly. Keep in mind that ultimately the alternator has to generate enough current to sustain the entire electrical load of the car's system while running at all times otherwise you battery would go dead over time.
Will the car fail to run if the battery is flat? Even if it is jumped to start. I think answer to this is yes too.
I don't know but it is probably very hard on the electronics if you attempt this as jumping a car produces huge spikes and electrical noise in the process.
So if I answered my questions correctly then Why will the car not run on the alternator.
Probably because of the electrical noise present.
So ultimate question is how large of a battery does one need for 993?
Large enough so that when the current drawn by engaging the starter does not drop the voltage on the system below the point where the ignition computer and system fails to cause ignition. With an inexpensive meter my battery at rest provides 12.5 volts, initiating the starter it drops to 10 volts and once the engine starts it sits between 13.9 and 14.2 at first. Turning a major eletrical load on such as the headlights or the A/C causes the number to drop 1/10th of a volt.
Hope my experience and opinions help here,
Andy