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Mon Jan 16, 2012 6:06 pm

I've got a '62 with a 1600+ motor and single weber progressive setup, but cannot seem to get the motor started unless the battery is connected to a charger. It's a brand new battery from Autozone, but it just doesn't seem to have the juice to get the motor to start.

Any suggestions on what size battery or cranking amps I might need?

Thanks!

Mon Jan 16, 2012 6:36 pm

You didn't say whether your 62 has been converted to 12 volts or not. In my 1960 bug with a group #1 - 6 volt battery, Cold Cranking amps are 625. In my 1970 12 volt bug -group #42, cold cranking amps are about 650. Some battery brands like "Optima" will even be higher. It would seem that if a new battery has to be connected to a charger to start the car, you likely have a bad battery. And yes, brand new batteries can be bad right off the shelf. It has happened to me especially on the 6 volt batteries. I would be taking it back to have it tested. Voltage at rest on a 6 volt should be at least 6.3 v and on a 12 volt about 12.6v. More important than that figure is the load test result. Have that test done as well. The fact that it starts with the charger would seem to indicate that starter, bushing and connections are OK. Always good to check those areas as well.

Mon Jan 16, 2012 7:45 pm

Sorry about that. It's 12v and the current battery is a Duralast group 42 with 500CCA. I haven't checked the starter and other items, but I will now. Thanks for the tip.

Mon Jan 16, 2012 9:37 pm

If you have a hydrometer you can check the specific gravity of each cell.
Or return it and have them load test it. May not be the battery.

Mon Jan 16, 2012 10:33 pm

A group #42 - 500 CCA battery with a full charge is certainly sufficient for starting purposes. Using the hydrometer to check a 6 volt battery with removable caps is easy. However, not so easy for the 12 volt battery. There are threads about doing a load test. If you have a volt meter(an excellent and very useful tool to own) you can do the test yourself. However, since it is a new battery under warranty, Autozone is going to have to test it anyways. For sure check battery cable connections.

Mon Jan 16, 2012 10:47 pm

wayne1230cars wrote: A group #42 - 500 CCA battery with a full charge is certainly sufficient for starting purposes. Using the hydrometer to check a 6 volt battery with removable caps is easy. However, not so easy for the 12 volt battery. There are threads about doing a load test. If you have a volt meter(an excellent and very useful tool to own) you can do the test yourself. However, since it is a new battery under warranty, Autozone is going to have to test it anyways. For sure check battery cable connections.

For a 12 volt battery, a load test consist of loading the battery through a carbon pile and it should hold 9.6 volts against a 180 amp draw through the carbon pile in the tester for 15 seconds-if it drops below 9.6 the battery is either discharged or toast....you cannot do this with a volt meter! You need a VAT 28 or a VAT 40 which has a amp meter/ volt meter and the carbon pile. The big dial in the middle loads the battery;
http://bambam.gmu.edu/sun/index_files/image14111.jpg

D.

Tue Jan 17, 2012 12:16 am

This the tool I use to do a battery load test. You can use it as a volt meter as well to check charging system. They are not very expensive and are OK for occasional use. I think I paid about $25 or $30 for it on sale at TSC a few years ago. I did see a tester at a garage sale last summer like the photo Helfen posted. I wish I had bought it but I didn't.
You may find a thread on Samba that will talk about using a "digital voltmeter" to check for amount of voltage drop at the battery as you try to start the car. I believe though a true load test involves the 15 second time span as mentioned by Helfen. On the tester that I have, that involves holding the toggle switch engaged for that time span and observing needle position - OK - weak -bad..[img][/img]

Tue Jan 17, 2012 12:51 am

a bad starter bushing will cause the amperage demand of the starter to go really high.

Tue Jan 17, 2012 8:03 am

Bruce wrote: a bad starter bushing will cause the amperage demand of the starter to go really high.

Very true. So do the load test to determine battery condition. If it passes that test, then start investigating other areas like bushing. The fact that it will start with a charge suggests that it may be battery. Let us know what you find.

Tue Jan 17, 2012 11:14 am

Quote: I believe though a true load test involves the 15 second time span as mentioned by Helfen.

This is very true. It also involves a specific load, as also mentioned by Helfen.

However, precise measurements using specific loads and specialized meters generally are NOT necessary for the amateur mechanic to eliminate the battery as a source of starter trouble. In my own personal experience, every single time a battery has passed a test using a simple volt meter for measurement and the starter as a load, it has been good; and every single time it has failed this test, it has been bad..

Undoubtedly, there will be a small but statistically significant number of cases where batteries will pass the simple home load test, and still be bad, and such cases will usually be caught out by a specialized load tester; however, non-professional mechanics should in no way be discouraged from performing a load test using a simple meter and a battery just because they have no specialized load tester handy, as a standard voltmeter and the starter as a load is a very useful and accurate set of tools for quick troubleshooting.

Tue Jan 17, 2012 11:37 am

[quote="Hammarlund"] Quote: I believe though a true load test involves the 15 second time span as mentioned by Helfen.

This is very true. It also involves a specific load, as also mentioned by Helfen.

However, precise measurements using specific loads and specialized meters generally are NOT necessary for the amateur mechanic to eliminate the battery as a source of starter trouble. In my own personal experience, every single time a battery has passed a test using a simple volt meter for measurement and the starter as a load, it has been good; and every single time it has failed this test, it has been bad..

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This is true, in the old days without a tester the method was; charge the battery---wait until the surface charge goes down, then turn your lights on....and crank the engine. If the engine wouldn't crank and the headlamps went out the battery was sulfated.
D.