Reply
 
Thread Tools Search this Thread Display Modes
 
Old 08-01-2013, 10:33 AM   #1
Rivet Master
Commercial Member
 
Moonstruck's Avatar
 
1986 31' Sovereign
1975 25' Tradewind
1967 17' Caravel
Sherfield English , Hampshire
Join Date: Oct 2006
Posts: 700
Send a message via MSN to Moonstruck Send a message via Yahoo to Moonstruck
Help! Help! Positive Ground Tow Vehicle

Good Morniing America!

Can anyone please help?

I am fitting a Prodigy RF to an Avion. A very pretty trailer with a very pretty tow vehicle - a 51 Chevy pick-up

Only problem, the Chevy is POSITIVE EARTH!!!

I can't see how to reconcile the positive vehicle power going through the hitch AND powering the brakes??

Advice soon please! This is a live job on a countdown
__________________

__________________
Silvertwinkie
Hampshire, UK
Moonstruck is offline   Reply With Quote
Old 08-01-2013, 10:46 AM   #2
Rivet Master
 
mimiandrews's Avatar
 
1966 22' Safari
Hilltop Lakes , Texas
Join Date: Jun 2008
Posts: 1,632
Just a guess...

Would separate wiring from the brakes to the controller work? In other words, disconnect the brake ground (earth) cable from the trailer frame, and connect it to a wire that runs to the negative side of the controller--wire size adequate for the current, of course.

I claim no experience whatsoever in doing this, so accept or reject this idea as you see fit.

Good luck!
__________________

mimiandrews is offline   Reply With Quote
Old 08-01-2013, 10:51 AM   #3
Figment of My Imagination
 
Protagonist's Avatar
 
2012 Interstate Coach
From All Over , More Than Anywhere Else
Join Date: Dec 2011
Posts: 10,873
Quote:
Originally Posted by mimiandrews View Post
Would separate wiring from the brakes to the controller work? In other words, disconnect the brake ground (earth) cable from the trailer frame, and connect it to a wire that runs to the negative side of the controller--wire size adequate for the current, of course.

I claim no experience whatsoever in doing this, so accept or reject this idea as you see fit.

Good luck!
If you do that, the power for the brake controller would have to be provided by a 12v-to-12v isolation transformer, which should allow you to reverse the polarity by hooking one side up backwards.

But that doesn't help with the lights, only the brakes.
__________________
I thought getting old would take longer!
Protagonist is offline   Reply With Quote
Old 08-01-2013, 10:57 AM   #4
Rivet Master
 
overlander63's Avatar

 
1993 21' Sovereign
Colfax , North Carolina
Join Date: Jun 2003
Posts: 21,134
Quote:
Originally Posted by Protagonist View Post
But that doesn't help with the lights, only the brakes.
Light bulbs don't care if they are positive or negative earth.
Honestly, neither do the brake magnets.
__________________
Terry
overlander63 is offline   Reply With Quote
Old 08-01-2013, 11:03 AM   #5
Home of Vortex tuning
 
CDONA's Avatar
 
2013 27' FB Eddie Bauer
Spearfish , South Dakota
Join Date: Dec 2009
Posts: 604
Images: 10
I've never heard of an american vehicle with a positive ground. Our trucks were 6 volt negative ground until they went 12 volt around late 50's early 60's.
I had issues with installing a 8 track player ( I'm old) in my '58 MGA.
I had a separate battery to power it and mounted the case without grounding it to avoid this problem.
Unless you totally insulate the hitch from frame grounding there will be issues.
Somewhere in that '51's life it was converted 6/12 volt, +/- flipped.
__________________
"Chip Tank" is in Morro Bay Ca.
CDONA is offline   Reply With Quote
Old 08-01-2013, 11:28 AM   #6
Rivet Master
 
arodriguez60's Avatar
 
2008 27' Classic FB
1959 22' Flying Cloud
fairview , New Mexico
Join Date: Mar 2005
Posts: 575
Images: 85
What you need is a new voltage regulator for the pickup that is neg ground. Swap the wires for the amp gauge reverse the battery cables . Then polarize the reulator per instructions on the reg. And then you have a neg ground system.
__________________



Avion C11
1959 Flying Cloud
1969 Tradewind
1973 Safari
1983 34 ft Limited
2004 F250 superduty ext cab
2014 F350 longbed superduty crewcab
arodriguez60 is offline   Reply With Quote
Old 08-01-2013, 11:28 AM   #7
Rivet Master
 
Jim Clark's Avatar
 
2012 28' International
Currently Looking...
New Orleans , Louisiana
Join Date: Apr 2002
Posts: 2,077
Images: 6
If the truck was converted to postive ground, may be easier to convert it back. I have 3 english sports cars and the 2 older ones are postive ground and the third is negative.
__________________
Jim N5TJZ Air# 174
2012 International Serenity 28
2005 Safari 25 SS Traded
1968 Globetrotter Sold
2011 F150 Ecoboost
Jim Clark is offline   Reply With Quote
Old 08-01-2013, 11:37 AM   #8
Rivet Master
 
arodriguez60's Avatar
 
2008 27' Classic FB
1959 22' Flying Cloud
fairview , New Mexico
Join Date: Mar 2005
Posts: 575
Images: 85
Here is a link on how it is done Change positive ground to negative old tractor
__________________



Avion C11
1959 Flying Cloud
1969 Tradewind
1973 Safari
1983 34 ft Limited
2004 F250 superduty ext cab
2014 F350 longbed superduty crewcab
arodriguez60 is offline   Reply With Quote
Old 08-01-2013, 12:03 PM   #9
Rivet Master
 
1977 Argosy 24
Currently Looking...
Milltown , Wisconsin
Join Date: Mar 2006
Posts: 1,079
As an old hot rodder, my advice is it's time to change the truck to negative ground. The only problem will be the radio if it has one.
ventport is offline   Reply With Quote
Old 08-01-2013, 01:50 PM   #10
Rivet Master
 
Jim Foster's Avatar
 
1965 17' Caravel
1983 27' Excella
Walnut Grove/Laguna Woods , California
Join Date: Jun 2004
Posts: 1,624
Send a message via Yahoo to Jim Foster
Quote:
Originally Posted by CDONA View Post
I've never heard of an american vehicle with a positive ground.
Hudsons were negative ground until they went to 12v in 1954 or 55.
__________________
Past President, El Camino Real Unit WBCCI#6620
Street Rod Builder (see avatar)
Kite flier (check out links below)
https://www.youtube.com/watch?v=Bp3nuNtlZcA&t=331s
https://www.youtube.com/my_videos?feature=mhee
Jim Foster is offline   Reply With Quote
Old 08-01-2013, 01:51 PM   #11
Rivet Master
Commercial Member
 
Moonstruck's Avatar
 
1986 31' Sovereign
1975 25' Tradewind
1967 17' Caravel
Sherfield English , Hampshire
Join Date: Oct 2006
Posts: 700
Send a message via MSN to Moonstruck Send a message via Yahoo to Moonstruck
Quote:
Originally Posted by ventport View Post
As an old hot rodder, my advice is it's time to change the truck to negative ground. The only problem will be the radio if it has one.
"Funny", my friend has a friend who is a hot rodder! I'm positive changing the polarity will solve it! The "stock" answer!

Sorry, couldn't resist it!
Attached Thumbnails
Click image for larger version

Name:	image-1252957396.jpg
Views:	157
Size:	590.2 KB
ID:	192179  
__________________
Silvertwinkie
Hampshire, UK
Moonstruck is offline   Reply With Quote
Old 11-05-2014, 07:07 PM   #12
2 Rivet Member
 
1978 Argosy 24
MooreHaven , Florida
Join Date: Jun 2012
Posts: 75
Fords were positive ground for many years,never saw a GM car with positive ground.That was common on english cars, to change it on them the fuel pump was a problem along with the fuel gauge and the radio and generator no simple job
__________________
This is only temporary unless it works! Red Green
oldiesel is offline   Reply With Quote
Old 11-11-2014, 02:53 PM   #13
Moderator dude
 
Action's Avatar

 
1966 26' Overlander
Phoenix , Arizona
Join Date: Apr 2002
Posts: 6,648
Images: 13
Quote:
Originally Posted by oldiesel View Post
Fords were positive ground for many years,....
Ford Motor company was 6V and positive ground up to 1955. In 1956 all Ford Motor Company US products went to 12 V negative ground.


>>>>>>>>>>Action
__________________
1966 Mercury Park Lane 4 DR Breezeway 410 4V, C-6, 2.80 - Streamless.
1966 Lincoln 4 door Convertible 462 4V 1971 Ford LTD Convertible 429 4V Phoenix ~ Yeah it's hot however it's a dry heat!
Action is offline   Reply With Quote
Old 11-18-2014, 10:51 AM   #14
Rivet Master
 
blkmagikca's Avatar

 
1987 32' Excella
Nepean , Ontario
Join Date: Mar 2006
Posts: 1,338
My 1999 Dodge Ram 2500 with Cummins Diesel came from the factory with a positive ground. It also has a factory-installed Bargman connector for the umbilical cord.
__________________
VE3JDZ
AIR 12148
1987 Excella 32-foot
1999 Dodge Ram 2500HD Diesel
WBCCI 8080
blkmagikca is offline   Reply With Quote
Old 11-18-2014, 11:22 AM   #15
Slide Out Society #001
 
GCinSC2's Avatar
 
2007 30' Classic S/O
Somewhere , South Carolina
Join Date: Apr 2010
Posts: 3,595
Quote:
Originally Posted by blkmagikca View Post
My 1999 Dodge Ram 2500 with Cummins Diesel came from the factory with a positive ground.

Care to check this or prove somehow?

Wishing the OP luck, just challenging the Dodge statement.

My 1997 and 2005 Dodge Cummins each have two batteries.
__________________
S/OS #001
2005 Dodge Ram 2500 5.9L 6 Speed
16" Michelins, Hi Spec Wheels, Max Brake, Carslile Actuator, Equal-i-zer, Dill TPMS. Campfire cook.
GCinSC2 is offline   Reply With Quote
Old 11-18-2014, 11:44 AM   #16
CHIEF THINGAMAJIG FIXER
 
1964 26' Overlander
bugtussel , South Carolina
Join Date: Mar 2014
Posts: 47
Wasn't going to say anything because I didn't know if it might be a canadian thing but I second the Ram observation. Positive ground????
Bugtussel is offline   Reply With Quote
Old 11-18-2014, 12:03 PM   #17
Rivet Master
 
J. Morgan's Avatar
 
1972 31' Sovereign
1975 31' Excella 500
Currently Looking...
Benton , Arkansas
Join Date: Mar 2013
Posts: 5,868
Images: 11
Really old thread, but really there isn't any issue when switching a vehicle from positive to negative ground.

Gauges don't care, starter doesn't care, most other electric motors don't care, lights don't care...

Therefore the easiest solution is to convert the vehicle to negative ground and 12volts at the same time.

Going to 12 volts isn't a challenge either, just a few more simple fixes.


1/2 Ton 4WD Truck, 72 Sovereign Hensley Arrow
__________________
The fact that I am opinionated does not presuppose that I am wrong......

J. Morgan is offline   Reply With Quote
Old 11-18-2014, 12:25 PM   #18
Slide Out Society #001
 
GCinSC2's Avatar
 
2007 30' Classic S/O
Somewhere , South Carolina
Join Date: Apr 2010
Posts: 3,595
Disagree.

Modern vehicles are packed with electronics and computers.
__________________
S/OS #001
2005 Dodge Ram 2500 5.9L 6 Speed
16" Michelins, Hi Spec Wheels, Max Brake, Carslile Actuator, Equal-i-zer, Dill TPMS. Campfire cook.
GCinSC2 is offline   Reply With Quote
Old 11-18-2014, 12:48 PM   #19
Moderator dude
 
Action's Avatar

 
1966 26' Overlander
Phoenix , Arizona
Join Date: Apr 2002
Posts: 6,648
Images: 13
By the mid to late 1950s all US built vehicles were negative ground. Most of the vehicles built in the UK (no matter the builder like Ford of England) were postive ground (earth) until the late 1960s with Austin holding out to 1971. Many of these have been coverted to negative ground.

Since about 1968 when electronic devices (mostly ignition products) were introduced on US built automobiles to start to comply with GVT regulation, the ground side of the system becomes very important as electronic devices require a clean and strong electrical signal from both sides. Many vehicles that had early electronic devices also had a new additional ground wire instead of relying on the engine block or frame as a good source of ground. This was to get a clean ground signal for the electronic device.

>>>>>>>>>>>>>Action
__________________
1966 Mercury Park Lane 4 DR Breezeway 410 4V, C-6, 2.80 - Streamless.
1966 Lincoln 4 door Convertible 462 4V 1971 Ford LTD Convertible 429 4V Phoenix ~ Yeah it's hot however it's a dry heat!
Action is offline   Reply With Quote
Old 11-18-2014, 02:18 PM   #20
Rivet Master
 
J. Morgan's Avatar
 
1972 31' Sovereign
1975 31' Excella 500
Currently Looking...
Benton , Arkansas
Join Date: Mar 2013
Posts: 5,868
Images: 11
Help! Help! Positive Ground Tow Vehicle

But I cant name a single car that uses any kind of computer that left the factory with a positive ground system.

As stated above, the last American vehicle to have positive ground lest the factory in 55.

I happen to own one of these cars that I converted to 12 volts and negative ground in just a little time, for not a lot of money.

http://i245.photobucket.com/albums/g...Sonoma-1-1.jpg

As an aside, pointless trivia, there are many who contend that positive ground is superior to negative ground in the transmission of power throughout a vehicle.

1/2 Ton 4WD Truck, 72 Sovereign Hensley Arrow
__________________

__________________
The fact that I am opinionated does not presuppose that I am wrong......

J. Morgan is offline   Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search
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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by the Airstream, Inc. or any of its affiliates. Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.



All times are GMT -6. The time now is 11:55 PM.


Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2020, Jelsoft Enterprises Ltd.