6v Battery - poor starting issues.

[Nicole F]

Hi there! New to the forum and classic car ownership. We just bought a 1946 Ford Super Deluxe Convertible - beautifully restored, almost all original. The engine was certified by the dealership (Wagner’s in KS) but we’ve been having starting issues. Since this is my first experience with a classic car, I don’t know what’s normal. Since we got it, if cold, it takes many tries to catch and start. Yesterday it started once, died, and then wouldn’t even turn over. So I bought a 6/12v battery tender and after about 4 hours in the tender, it started up first try - better than it ever has! I left it on the tender all night and it’s still registering as “charging.” Hmmm. This is a pic of the battery. It looks new. But maybe I need to have it tested? Maybe I need higher CCAs since this is only 640? Do these batteries need to just be left on the tender always? My big fear is driving it somewhere and then it not starting. For obvious reasons the 6vs can’t be jumped by a new car!

 

thanks for your help!!

[Alex D.]

6volts can be jumped by a new car. make sure all lights and accessories are turned off and remove cables as soon as it starts.

Make sure cables are tight and good grounds. Six-volt systems require heavier battery cables than what you see on a 12-volt system.

[39BuickEight]

Hello!

 

With a properly connected system, the battery should last over a month and still be good to start the car.  Mine goes 2-3 months and does fine. 
 

Maintainers, depending on how they function (different ones are designed to do different things) can take days and days to fully charge a battery.  Some will never do it if the battery isn’t good enough to start with.

 

6 volt cars can be jumped by 12 volt cars.  I’ve done it many times back when mine was still a project.   I’ve heard issues regarding bulbs and things can happen, but I’ve never seen it myself.

 

 

[JACK M]

I keep several cars on tenders.

They are all on timers at one hour per day.

Probably not what your problem is here. I would have that battery tested.

By the way when testing a battery it has to be fully charged.

 

See you at the local cruises.

 

[Joe Cocuzza]

Just a word of warning!!!!!

I used to keep my 6 volt battery connected to a BatteryMinder ALL THE TIME.

Then I noticed that the battery was dead. 

Turns out that, eventhough they say you can leave the charger on all the time, when I looked inside the battery it was bone dry.

This happened to a 12 volt motorcycle battery, too.

This can cause a fire eventually so be warned.

Now I use the Tenders every couple of weeks and let them charge a few days them disconnect them.

[plymouthcranbrook]

Have the battery load tested.  Be sure as mentioned that the cables are heavy enough( 1 gauge to 0 or 00).  Adding extra thick cables to make sure the engine is grounded well to the frame often helps as well.  I have left the tenders on my 6 volt Plymouth all winter and have had some batteries last five years or more. Weak Grounds are often a cause of hard starting,

[TerryB]

Slowly charging is good in that it doesn’t bake the battery cells dry.  Those caps on the battery can be removed and you can see how much water is in each of the three cells.  If you remove the battery charger and wait an hour or two for the battery to cool you can check the amount of water in the cells by looking into the cell and seeing if the water is above the battery plates.  If it is it’s good, ok, if not add some distilled water to the cell until the water is just covering the plates.  Do not fill to the top of the cell!  There has to be room for expansion of the water when the battery is charging.  Replacing the battery is not unusual in old cars like yours that get infrequent use.  The indication that the car started much better after time on the battery charger seems to indicate it is need of a re-charging at minimum or replacement if it can’t hold a charge.  Good luck!

Edited May 21, 2022 by TerryB (see edit history)

[Nicole F]

2 hours ago, Joe Cocuzza said:

Just a word of warning!!!!!

I used to keep my 6 volt battery connected to a BatteryMinder ALL THE TIME.

Then I noticed that the battery was dead. 

Turns out that, eventhough they say you can leave the charger on all the time, when I looked inside the battery it was bone dry.

This happened to a 12 volt motorcycle battery, too.

This can cause a fire eventually so be warned.

Now I use the Tenders every couple of weeks and let them charge a few days them disconnect them.

Yikes! Now I’m worried about my Harley. It’s been on a tender all winter. Thanks for the heads-up!

[kings32]

I leave battery tender on all my cars all the [ for years] I get about 10 years out of a battery ,never had a problem . 

[zeke01]

Battery tender-battery Minder: Big difference. Zeke

Edited May 21, 2022 by zeke01 (see edit history)

[Joe Cocuzza]

2 hours ago, Nicole F said:

Yikes! Now I’m worried about my Harley. It’s been on a tender all winter. Thanks for the heads-up!

And this happened to my friends Quad, too.

So, people will say it's okay, never had a problem, etc. but I have seen 3 instances where the Tender being on the battery ALL the time dried the battery out and killed it.

I believe it is best to be cautious. 

We have to remember we are dealing with electricity/electronics and things can vary.

One other incident I had was I bought a brand new BatteryTender and connected it to my 6 volt battery and plugged it in.

Luckily I did this while I was home. About 20 minutes later I went to check on it ( I always do) and the BRAND new Tender was burning up and smoking. If I wasn't around to catch it there would have been a fire for sure.

Not trying to scare anyone just issuing words of caution from my experience(s)

[Nicole F]

5 hours ago, plymouthcranbrook said:

Have the battery load tested.  Be sure as mentioned that the cables are heavy enough( 1 gauge to 0 or 00).  Adding extra thick cables to make sure the engine is grounded well to the frame often helps as well.  I have left the tenders on my 6 volt Plymouth all winter and have had some batteries last five years or more. Weak Grounds are often a cause of hard starting,

Thanks! Are these thick enough?

[Joe Cocuzza]

11 minutes ago, zeke01 said:

Barry tender-battery Minder: Big difference. Zeke

What difference(s).

I use BatteryMinders as the quality of the BatteryTender has gone down since they started making them in China. 

Also, in my post about the new one burning up....it was a BatteryTender.

 

Don't want to hijack this thread soooooooo......

It appears that either the battery is bad or something else is drawing the battery down.

[Nicole F]

5 hours ago, 39BuickEight said:

Hello!

 

With a properly connected system, the battery should last over a month and still be good to start the car.  Mine goes 2-3 months and does fine. 
 

Maintainers, depending on how they function (different ones are designed to do different things) can take days and days to fully charge a battery.  Some will never do it if the battery isn’t good enough to start with.

 

6 volt cars can be jumped by 12 volt cars.  I’ve done it many times back when mine was still a project.   I’ve heard issues regarding bulbs and things can happen, but I’ve never seen it myself.

 

 

Thank you! As others have suggested too, I think I need to have it tested. 

Edited May 21, 2022 by Nicole F (see edit history)

[Joe Cocuzza]

11 minutes ago, Nicole F said:

Thanks! Are these thick enough?

They look correct.

Also, I would suggest you remove the zip tie holding the battery cable to the heater hose. This will eventually result in the zip tie cutting through that hose. OR, you can put a rubber cushion (I use pipe insulation) between (around) the hose and the zip tie.

And take a look at that same hose resting up against the battery hold down wing nut. Metal will always win out over rubber......

[Nicole F]

11 minutes ago, Joe Cocuzza said:

They look correct.

Also, I would suggest you remove the zip tie holding the battery cable to the heater hose. This will eventually result in the zip tie cutting through that hose. OR, you can put a rubber cushion (I use pipe insulation) between (around) the hose and the zip tie.

And take a look at that same hose resting up against the battery hold down wing nut. Metal will always win out over rubber......

Thanks! That may be something I can actually do myself! Lol. 

[Larry Schramm]

1 minute ago, Nicole F said:

Thanks! That may be something I can actually do myself! Lol. 

 

I would take the ground wire off the block and make sure that it is super clean.  Both the block and the end of the cable.  Any dirt, grunge, paint can cause the car not to start.  High resistance point. It would probably be good to check the other end of the positive cable.

[Tom Boehm]

I want to stress good advice from previous responses: 6 volt systems can work well but they are not as forgiving as 12 volt. Make sure all the contacts on the other end of the battery cables are clean of rust, dirt, and paint. This also goes for the ground straps between the engine and the frame. It also made a difference on my car to clean the dirt, rust, and paint for the surface where the starter touches the engine block/bell housing. If the engine continues to turn over slow you can have thicker battery cable made from 00 welding cable at YnZ or Rhode Island auto wiring.  All these steps remove resistance to the free flow of current. The battery doesn't have to work as hard and the starter spins the engine faster and it starts faster. You won't run the battery down as much starting the engine. 

[Bloo]

Your cable looks big enough, but is the ground connected to the firewall in the picture? Maybe someone more familiar with 46 Fords can comment on that. It doesn't sound right to me but it could be.

 

Regarding the cables, follow the path the current takes with your eyes, from the battery post, to the starter solenoid, to the starter, and then don't forget the ground side. The starter case is bolted to the engine/transmission/bellhousing assembly somehow, and then the current flows from the engine/transmission/bellhousing through more cable back to the battery. All if it must be big and have clean connections.

 

For example on some cars there is a ground cable from the engine/transmission/bellhousing right back to the battery post. On a lot of other cars, there is a cable from the engine/transmission/bellhousing to the frame, and then another cable from the frame back to the battery post. Either setup is fine. Those braided cables are often used on the grounded side of the circuit. They are fine. However Ford wired it, everything must be equally large and the connections equally good from one battery post to the starter and from the starter all the way back to the other battery post.

 

Edited May 21, 2022 by Bloo (see edit history)

[Nicole F]

8 minutes ago, Bloo said:

Your cable looks big enough, but is the ground connected to the firewall in the picture? Maybe someone more familiar with 46 Fords can comment on that. It doesn't sound right to me but it could be.

 

Regarding the cables, follow the path the current takes with your eyes, from the battery post, to the starter solenoid, to the starter, and then don't forget the ground side. The starter case is bolted to the engine/transmission/bellhousing assembly somehow, and then the current flows from the engine/transmission/bellhousing through more cable back to the battery. All if it must be big and have clean connections.

 

For example on some cars there is a ground cable from the engine/transmission/bellhousing right back to the battery post. On a lot of other cars, there is a cable from the engine/transmission/bellhousing to the frame, and then another cable from the frame back to the battery post. Either setup is fine. Those braided cables are often used on the grounded side of the circuit. They are fine. However Ford wired it, everything must be equally large and the connections equally good from one battery post to the starter and from the starter all the way back to the other battery post.

 

Thank you! Now if I only knew what all of those other parts look like. Lol. I am VERY new at this so I really don’t even have a basic understanding of the parts of a car engine. I wish there was some sort of classic car training courses (YouTube tutorials?) so I could learn how to troubleshoot and do basic repairs. Any suggestions would be greatly appreciated!

[Larry Schramm]

Also, if there is a terminal on the end of the positive cable, you can solder it and it will eliminate another possible high resistance point.

 

Good soldering fixes a host of bad crimps, etc..

[maok]

It sounds like you just need a new battery.

[Matt Harwood]

Also check your voltage at the battery while it's running. I noticed in your photos in your other thread about temperatures that your car has been modified with an alternator. It's possible that alternator isn't putting out any electricity (or not enough). It should show 7.5-8.5 volts at the battery while it's running to indicate it's charging. If your battery is weak, a few hours on a tender won't bring it back--it could take days given the few milliamps that most tenders put out. If the battery is soft and the alternator isn't putting out any juice, then you could be running out of electricity, a situation that's exacerbated by heat, and that would give you the symptoms you're seeing. So make sure the whole charging system is healthy starting with a voltage test. Then make sure the battery is fully topped off and if the battery is not taking a full charge, replace it. 

 

Hope this helps!

[Larry Schramm]

Matt makes a good point about checking the batter voltage while running.  Another good check is to put a volt meter on the battery, have someone try to start the car while having the volt meter on the battery.  If you get less than about 4.5 volts while trying to start the car with a charged battery, the battery is bad.

[Nicole F]

3 minutes ago, Matt Harwood said:

Also check your voltage at the battery while it's running. I noticed in your photos in your other thread about temperatures that your car has been modified with an alternator. It's possible that alternator isn't putting out any electricity (or not enough). It should show 7.5-8.5 volts at the battery while it's running to indicate it's charging. If your battery is weak, a few hours on a tender won't bring it back--it could take days given the few milliamps that most tenders put out. If the battery is soft and the alternator isn't putting out any juice, then you could be running out of electricity, a situation that's exacerbated by heat, and that would give you the symptoms you're seeing. So make sure the whole charging system is healthy starting with a voltage test. Then make sure the battery is fully topped off and if the battery is not taking a full charge, replace it. 

 

Hope this helps!

Thanks Matt! Would something like this work? Probably should have this anyway. 

[Xander Wildeisen]

You might check the starter relay. Older ones you can take apart and clean. Just a copper disk that makes contact on two terminals, and allows power to pass through the relay to the starter. That copper disk and terminals gets burnt, pitted and corroded over time. The copper disk can also rotate, causing problems sometimes but not all the time. Easy to pull apart by yourself and clean.

[keithb7]

I run a You Tube channel. Its focused on vintage Mopars however it is relevant to all old flatheads from about ‘53 back.  I try to explain things simply for beginners. 
 

Here are a couple examples. There are many videos covering various topics. 
 

 

 

Edited May 22, 2022 by keithb7 (see edit history)

[Nicole F]

1 hour ago, keithb7 said:

I run a You Tube channel. Its focused on vintage Mopars however it is relevant to all old flatheads from about ‘53 back.  I try to explain things simply for beginners. 
 

Here are a couple examples. There are many videos covering various topics. 
 

 

 

Amazing!! Thank you!!

[MCHinson]

Welcome to the AACA Discussion Forum. As has been stated above, in a 6 volt system, clean tight connections in all of the electrical connections are very important. The charging system must also be putting out adequate current to charge the battery, and the battery has to be in good shape.

 

A couple of additional suggestions for you. First, I suggest you buy a factory shop manual for your car. It will help you as you learn more about the car's systems. It will also help answer the question of where the ground wire should be connected, although I think it is correct for a 46 Ford, despite that not being where most cars would have the ground cable connected. Youtube is also going to be a great help.

 

Most importantly, join a local Antique Automobile Club of America Region. You should find local members who will be able and willing to help you learn more about maintaining your antique car. This forum is great but there is nothing else that is as helpful as a local experienced old car hobbyist who can meet you in person and help you learn about old cars. While there are not many regions out west, in Portland, you are not too far from a local region. The AACA website shows the following:

 

Region

Fort Vancouver/Rose City Region

First Name

Dave

Last Name

Newland

Address

9008 NE 101st St

City

Vancouver

State

WA

Zip

98662-1959

Country

USA

Email

royalmail17@aol.com

 

[Bhigdog]

Replace both cables using 6V size cable. Run the ground cable directly to the block with a smaller frame to body strap. CLEAN, CLEAN, CLEAN connections. Did I say CLEAN connections? .............Bob

Edited May 22, 2022 by Bhigdog (see edit history)

[john hess]

what Bloo said.... that ground to firewall as only ground point is suspicious.... feel that cable after a start attempt..... my guess is that it will be HOT.... you need a good (heavy) ground wire to BLOCK, frame or both... cant have to many ground points.... 

[john hess]

Also guys, and ladies.... this battery is hooked up as (+) ground... look at photo closely... not familiar with 49 ford, or positive ground.... but if its correct, do you still hook (-) negative (black) wire from charger to (-) negative post on battery ?

[PONTIAC1953]

19 hours ago, Alex D. said:

6volts can be jumped by a new car. make sure all lights and accessories are turned off and remove cables as soon as it starts.

Make sure cables are tight and good grounds. Six-volt systems require heavier battery cables than what you see on a 12-volt system.

also the ford is positive ground, all new vehicles are negative ground, the 12 volt negative ground car should have everything turned off, better yet have one battery cable disconnected.

[PONTIAC1953]

2 minutes ago, john hess said:

Also guys, and ladies.... this battery is hooked up as (+) ground... look at photo closely... not familiar with 49 ford, or positive ground.... but if its correct, do you still hook (-) negative (black) wire from charger to (-) negative post on battery ?

yes, still connect the positive charger or tender wire (+) to the positive battery post.

[PONTIAC1953]

14 hours ago, Nicole F said:

Thanks! Are these thick enough?

I see your positive ground cable bolted to the firewall, I'm sure your starter solenoid is firewall mounted too, I would certainly look into running another ground cable from the firewall connection going to the cylinder head or engine block.

[trimacar]

The ground to the firewall is fine for accessories, but NOT for starting car.  Run a ground cable directly to a starter mounting bolt, making sure all metal to metal is free of dirt and paint.  You’ll be amazed at how much better it starts.

[PONTIAC1953]

17 hours ago, Nicole F said:

Yikes! Now I’m worried about my Harley. It’s been on a tender all winter. Thanks for the heads-up!

batteries that are not sealed, need periodic attention to the water level in each cell, enough water to cover the plates inside and about halfway from the plates up to the holes for the caps.

[VW4X4]

21 hours ago, Alex D. said:

6volts can be jumped by a new car. make sure all lights and accessories are turned off and remove cables as soon as it starts.

Make sure cables are tight and good grounds. Six-volt systems require heavier battery cables than what you see on a 12-volt system.

This is absolutely not true, and COULD even be dangerous.  Its the equivalent of putting 600 LB's of pressure in a 300LB hose. It might hold.  It might blow out.  IT might blow out and kill someone.  Same with electricity. Things might work. Things might burn.  Things like the battery might blow up in your face. 

ERIC

PS  This is exactly why Apollo 13 blew up.

Edited May 22, 2022 by VW4X4 (see edit history)

[charlespetty]

I once melted a pair of jumper cables jumping a six volt car with a twelve volt car.  Not recommended!

[alsancle]

1 hour ago, Bhigdog said:

Replace both cables using 6V size cable. Run the ground cable directly to the block with a smaller frame to body strap. CLEAN, CLEAN, CLEAN connections. Did I say CLEAN connections? .............Bob

This.

 

I think that 75% of all starter problems with six Volt systems end up being the wrong cables.

 

Also, the alternator conversion gives me pause.