Go Back   The Ford Barn > General Discussion > Early V8 (1932-53)

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Display Modes
Old 05-23-2014, 08:56 PM   #1
Brendan1959
Member
 
Brendan1959's Avatar
 
Join Date: Jul 2010
Location: Melbourne Australia
Posts: 95
Default 12 volt positive earth 46 coupe

Hi
looking for some advice, I thought my recently purchased 46 coupe was still 6 volt and running as a total loss system on a 12 volt battery. I bought a alternator, bracket coil and a electric wiper kit. someone had installed some sort of voltage dropping unit to supply the instruments. I was planning on a rewire as it all looked a bit dodgy. I had checked the volts at the battery with the motor running, no charge. I was just about to start ripping in to it when I thought I would test the battery voltage again, started it up put the meter on the battery no charge, upped the revs a bit and up came the volts. Good news I thought I can stay with the generator. There is no vacuum unit for the wipers hence the vintique wipers conversion. Has anyone used one of these with positive earth?.

Brendan
Attached Images
File Type: jpg photo.jpg (75.5 KB, 47 views)
File Type: jpg photo 1.JPG (127.7 KB, 54 views)
File Type: jpg photo 2.JPG (123.1 KB, 56 views)

Last edited by Brendan1959; 05-23-2014 at 10:02 PM.
Brendan1959 is offline   Reply With Quote
Old 05-23-2014, 10:36 PM   #2
fordor41
Senior Member
 
fordor41's Avatar
 
Join Date: Oct 2011
Location: elmira,ny
Posts: 1,505
Default Re: 12 volt positive earth 46 coupe

Must motors will run on + or - gnd. They just run backwards. Don't see any problem with a wiper motor. Also a lot of stock gauges don't operate on 12V so they installed a 12-6V reducer
fordor41 is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 05-24-2014, 03:50 AM   #3
scooder
Senior Member
 
Join Date: Jul 2010
Posts: 2,593
Default Re: 12 volt positive earth 46 coupe

Most motors will run positive or negative ground, with no problem. Very rare for one to run backwards when you swap polarity.
Ask vintique, incase there's something electronic in the wipers that's polarity sensitive. If there is you'd have to isolate the wipers from ground, might be tricky, I'd be surprised if there was.
Martin.
scooder is offline   Reply With Quote
Old 05-24-2014, 07:09 PM   #4
Ab4875
Senior Member
 
Ab4875's Avatar
 
Join Date: Dec 2013
Location: Sydney, Australia
Posts: 112
Default Re: 12 volt positive earth 46 coupe

Hi Brendan, I have a 46 business coupe. It was originally a New Zealand car. I bought it last November.

I am running 6 volt positive earth. I bought one of the electric wiper kits but haven't fitted it yet.

I'm pulling the motor at the moment. Once I get that back in I'll install the wiper kit. I'll let you know how it goes.

Are you going to Dubbo?
Ab4875 is offline   Reply With Quote
Old 05-24-2014, 10:04 PM   #5
Brendan1959
Member
 
Brendan1959's Avatar
 
Join Date: Jul 2010
Location: Melbourne Australia
Posts: 95
Default Re: 12 volt positive earth 46 coupe

Thanks all
I bench ran it positive and negative ground and it seems to be ok. I did email the manufacturer a week or so ago but got no reply.
Brendan
Brendan1959 is offline   Reply With Quote
Old 05-24-2014, 10:40 PM   #6
fordor41
Senior Member
 
fordor41's Avatar
 
Join Date: Oct 2011
Location: elmira,ny
Posts: 1,505
Default Re: 12 volt positive earth 46 coupe

Sponsored Links (Register now to hide all advertisements)
Quote:
Originally Posted by scooder View Post
Most motors will run positive or negative ground, with no problem. Very rare for one to run backwards when you swap polarity.
Ask vintique, incase there's something electronic in the wipers that's polarity sensitive. If there is you'd have to isolate the wipers from ground, might be tricky, I'd be surprised if there was.
Martin.
"very rare for one to run backwards"- Really?
fordor41 is offline   Reply With Quote
Old 05-25-2014, 05:44 AM   #7
scooder
Senior Member
 
Join Date: Jul 2010
Posts: 2,593
Default Re: 12 volt positive earth 46 coupe

Yeah really. I've never had a motor run backwards after a polarity change on a car. Wether it be wiper motor or fan motor or starter or whatever. Not saying it can't happen on any electric motor, just that it's rare on an automotive motor.
If my brain is working correctly, a permanent magnet motor will reverse if you swap the polarity. But the type found in autos is almost exclusively Not Perminant magnet type.
The heater motor used in some of the 40's era Ford's have a reversing function, but I never played with one. I believe the motor is built specifically for this function, not just a polarity swap at the switch. Maybe some one who has played with one could tell us how that motor is wired.
Martin.
scooder is offline   Reply With Quote
Old 05-25-2014, 07:52 AM   #8
Walt Dupont--Me.
Senior Member
 
Walt Dupont--Me.'s Avatar
 
Join Date: May 2010
Location: Gardiner Me.
Posts: 4,200
Default Re: 12 volt positive earth 46 coupe

Quote:
Originally Posted by fordor41 View Post
Must motors will run on + or - gnd. They just run backwards. Don't see any problem with a wiper motor. Also a lot of stock gauges don't operate on 12V so they installed a 12-6V reducer
When your backing your car up you have to stop and change the batt cables around so you can go forward. The devil made me do it. Walt
Walt Dupont--Me. is offline   Reply With Quote
Old 05-25-2014, 08:22 AM   #9
Old Ford Addict
Senior Member
 
Old Ford Addict's Avatar
 
Join Date: Feb 2014
Location: Nor-Cal
Posts: 140
Default Re: 12 volt positive earth 46 coupe

And never bump into a - earth car … you’ll weld you’re bumpers together
Old Ford Addict is offline   Reply With Quote
Old 05-25-2014, 09:20 AM   #10
Mart
Senior Member
 
Mart's Avatar
 
Join Date: May 2010
Location: Solihull, England.
Posts: 8,732
Default Re: 12 volt positive earth 46 coupe

As it's 12V you might as well make it negative ground, Then you can use a lighter socket for things like sat nav, usb and phone charger etc. The alternator will be configured for negative earth too.

Mart.
Mart is offline   Reply With Quote
Old 05-25-2014, 04:54 PM   #11
Brendan1959
Member
 
Brendan1959's Avatar
 
Join Date: Jul 2010
Location: Melbourne Australia
Posts: 95
Default Re: 12 volt positive earth 46 coupe

Mart
I am still running what I think is the original 6 volt generator with what I think is a 12v regulator, so I dont think negative ground is possible with this setup?
Brendan
Brendan1959 is offline   Reply With Quote
Old 05-26-2014, 04:34 AM   #12
scooder
Senior Member
 
Join Date: Jul 2010
Posts: 2,593
Default Re: 12 volt positive earth 46 coupe

Dude, you said you had an alternator at first, Mart is bang on with his negative ground suggestion. I missed the alternator bit earlier, had I seen it I would have said the same, just go negative ground.
Now you say generator? What have you actually got? With this info you'll get the right answers.
For the record, any generator can be polarised (simple no tools) to work negative or positive ground.
Martin
scooder is offline   Reply With Quote
Old 05-26-2014, 05:14 AM   #13
Brendan1959
Member
 
Brendan1959's Avatar
 
Join Date: Jul 2010
Location: Melbourne Australia
Posts: 95
Default Re: 12 volt positive earth 46 coupe

Martin
I bought an alternator and bracket but hope not to fit it, so you say I can make the generator negative ground, how is it done?
Brendan
Brendan1959 is offline   Reply With Quote
Old 05-26-2014, 06:55 AM   #14
Mart
Senior Member
 
Mart's Avatar
 
Join Date: May 2010
Location: Solihull, England.
Posts: 8,732
Default Re: 12 volt positive earth 46 coupe

There are a lot of threads on the subject. Turn the battery round. Connect the battery cables. You might need to change the terminals as they are different sizes. Then you need to polarise the generator. Google it, I don't want to give duff info. (It involves flashing a wire across some terminals on the regulator - I think - google it).

You might need to reverse the terminals on your coil. not sure.

That's all that is involved. I don't think using a 6V generator on 12V is a good way to do it - again, google it, it can work, but you don't get the output you would with a proper 12V converted generator.

I have converted generators using a mix and match of old and later generator parts - it's all well documented - google is your friend.

Make sure all the bulbs have been switched over to 12V alternatives. You can use reducers or modern voltage regulators (electronic parts that cost pennys) to power the gauges.

Most importantly, do some research. Lots of info out there. If you can't find a specific answer to a question, just ask, but it is better to search for the info yourself than to just expect it to be handed on a plate for you.

Mart.

Last edited by Mart; 05-26-2014 at 07:01 AM.
Mart is offline   Reply With Quote
Old 05-26-2014, 10:35 AM   #15
B-O-B
Senior Member
 
B-O-B's Avatar
 
Join Date: May 2010
Location: Ft Mohave,Az
Posts: 1,984
Default Re: 12 volt positive earth 46 coupe

Well stated Mart. I've been suggesting using Google for years. Lots of great info on the web & faster to get the info you desire.
B-O-B is offline   Reply With Quote
Old 05-26-2014, 11:26 AM   #16
Old Ford Addict
Senior Member
 
Old Ford Addict's Avatar
 
Join Date: Feb 2014
Location: Nor-Cal
Posts: 140
Default Re: 12 volt positive earth 46 coupe

Quote:
Originally Posted by Brendan1959 View Post
Martin
, so you say I can make the generator negative ground, how is it done?
Brendan
Its however you have the battery hooked up when you polarize the system
Old Ford Addict is offline   Reply With Quote
Old 05-26-2014, 08:41 PM   #17
gearhead1952
Senior Member
 
gearhead1952's Avatar
 
Join Date: May 2010
Location: Julesburg, Colorado
Posts: 713
Default Re: 12 volt positive earth 46 coupe

Quote:
Originally Posted by scooder View Post
Yeah really. I've never had a motor run backwards after a polarity change on a car. Wether it be wiper motor or fan motor or starter or whatever. Not saying it can't happen on any electric motor, just that it's rare on an automotive motor.
If my brain is working correctly, a permanent magnet motor will reverse if you swap the polarity. But the type found in autos is almost exclusively Not Perminant magnet type.
The heater motor used in some of the 40's era Ford's have a reversing function, but I never played with one. I believe the motor is built specifically for this function, not just a polarity swap at the switch. Maybe some one who has played with one could tell us how that motor is wired.
Martin.
Yup. On a perm magnet motor the field windings are replaced by magnets so changing the polarity of the armature will change the rotation of the motor because the magnets haven't moved. Heater,starter and wiper motors have field windings so if polarity is reversed both the field and armature get reversed so rotation is the same. Speed control can be done by lowering the voltage to the fields.
gearhead1952 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 11:57 AM.