The Ford Barn

gkgeiger · 07-11-2012, 01:40 PM

I needed a temp gauge for my 39 and ended up buying a really nice complete set of 37 gauges. I'm in the process of changing them but ran into a small issue. My stock 39 ammeter has a metal bar running from a common positive terminal. My new 37 gauge doesn't have a threaded post but something different (see attached picture). I'm assuming I just make a jumper wire but have no idea what kind of terminal/connector to use on the gauge end. Does anyone have any help? Thanks in advance
37 ammeter

39 gauges

gkgeiger · 07-11-2012, 02:25 PM

The more I think about this and look at the other gauge the more I think a jumper isn't going to work. The whole back of the gauge it brass, so if I connected a pos. feed to it it would go straight to ground (dead short). Now I'm really confused. Does some kind of insulated wire go thru that terminal?

Bruce Lancaster · 07-11-2012, 02:40 PM

Ford ammeters from 1933 through somewhere into the '50's used the inductive loop. I think your bus-bar connected gauge must be a voltmeter...
What does it say on it and how is it calibrated?

gkgeiger · 07-11-2012, 02:47 PM

Hi Bruce,
Thanks for the response, you've helped me in the past. I just took another look at it and I believe you are correct. It says Batt. and the other says Amps. It reads L N and H. I think I'll put the 39 gauge in the 37 cluster. I like a volt meter better. I didn't realize they used them in that era.

Karl Wolf · 07-11-2012, 04:59 PM

Mine cluster looks like the picture of the back of yours... mine is a voltmeter, shows operating system volts rather than charging amps... Your single gauge picture is an amp meter... Voltmeter is what I prefer... There should be a bunch of them out there, and they're easier to hook up.
Karl

1938FordPickup · 07-11-2012, 05:15 PM

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A length of wire runs through this loop, usually from the battery to the starter, the direction of current is important too because the meter is reading the direction of current, look at a wiring diagram for the year of gauges

Mike in AZ · 07-11-2012, 05:54 PM

here's a link to MacVP's website, showing the wiring diagram for the '39.....looks like the bar is the hot feed...other goes to ground.....Mike

http://www.vanpeltsales.com/FH_web/F...ing1939dlx.jpg

David W Juliano · 07-11-2012, 06:09 PM

The 39 gauge set you show is for a Deluxe car and is wired for a battery gauge not an ammeter. Only 39 Standards had ammeters. If all you need is a 39 temp gauge and you have a working 37 temp gauge why not just swap face plates, that's the only difference between the 37 and 39.

gkgeiger · 07-11-2012, 06:47 PM

Quote:

Originally Posted by David W Juliano

The 39 gauge set you show is for a Deluxe car and is wired for a battery gauge not an ammeter. Only 39 Standards had ammeters. If all you need is a 39 temp gauge and you have a working 37 temp gauge why not just swap face plates, that's the only difference between the 37 and 39.

Thanks to everyone who replied. Yes, I could have done what you said but the cluster I got was nearly perfect so I used everything but the voltmeter.

Bruce Lancaster · 07-12-2012, 09:12 AM

If you are going to use tha ammeter, obviously you need to look over diagram from an ammeter equipped car, but from memory I think you will just be lengthening the big feed wire from starter solenoid (I think) to your circuit breakers so it can run through the loop. Important high amperage wire, so do good job. The former voltmeter feed would be removed leaving the remaining links that feed other gauges hooked up.

07-11-2012, 01:40 PM	#1
gkgeiger Senior Member Join Date: Nov 2010 Location: Akron, Ohio Posts: 299	37-39 instrument question I needed a temp gauge for my 39 and ended up buying a really nice complete set of 37 gauges. I'm in the process of changing them but ran into a small issue. My stock 39 ammeter has a metal bar running from a common positive terminal. My new 37 gauge doesn't have a threaded post but something different (see attached picture). I'm assuming I just make a jumper wire but have no idea what kind of terminal/connector to use on the gauge end. Does anyone have any help? Thanks in advance 37 ammeter 39 gauges __________________ Gene

07-11-2012, 02:25 PM	#2
gkgeiger Senior Member Join Date: Nov 2010 Location: Akron, Ohio Posts: 299	Re: 37-39 instrument question The more I think about this and look at the other gauge the more I think a jumper isn't going to work. The whole back of the gauge it brass, so if I connected a pos. feed to it it would go straight to ground (dead short). Now I'm really confused. Does some kind of insulated wire go thru that terminal? __________________ Gene

07-11-2012, 02:40 PM	#3
Bruce Lancaster Member Emeritus Join Date: May 2010 Location: Madison, NJ Posts: 5,230	Re: 37-39 instrument question Ford ammeters from 1933 through somewhere into the '50's used the inductive loop. I think your bus-bar connected gauge must be a voltmeter... What does it say on it and how is it calibrated?

07-11-2012, 02:47 PM	#4
gkgeiger Senior Member Join Date: Nov 2010 Location: Akron, Ohio Posts: 299	Re: 37-39 instrument question Hi Bruce, Thanks for the response, you've helped me in the past. I just took another look at it and I believe you are correct. It says Batt. and the other says Amps. It reads L N and H. I think I'll put the 39 gauge in the 37 cluster. I like a volt meter better. I didn't realize they used them in that era. __________________ Gene

07-11-2012, 04:59 PM	#5
Karl Wolf Senior Member Join Date: May 2010 Location: Mill Valley,Ca. Posts: 1,555	Re: 37-39 instrument question Mine cluster looks like the picture of the back of yours... mine is a voltmeter, shows operating system volts rather than charging amps... Your single gauge picture is an amp meter... Voltmeter is what I prefer... There should be a bunch of them out there, and they're easier to hook up. Karl

07-11-2012, 05:15 PM	#6
1938FordPickup Member Join Date: May 2012 Location: Massachusetts, USA Posts: 40	Re: 37-39 instrument question Sponsored Links (Register now to hide all advertisements) A length of wire runs through this loop, usually from the battery to the starter, the direction of current is important too because the meter is reading the direction of current, look at a wiring diagram for the year of gauges

07-11-2012, 05:54 PM	#7
Mike in AZ Senior Member Join Date: May 2010 Location: Waddell, AZ Posts: 2,540	Re: 37-39 instrument question here's a link to MacVP's website, showing the wiring diagram for the '39.....looks like the bar is the hot feed...other goes to ground.....Mike http://www.vanpeltsales.com/FH_web/F...ing1939dlx.jpg

07-11-2012, 06:09 PM	#8
David W Juliano Member Join Date: May 2010 Posts: 30	Re: 37-39 instrument question The 39 gauge set you show is for a Deluxe car and is wired for a battery gauge not an ammeter. Only 39 Standards had ammeters. If all you need is a 39 temp gauge and you have a working 37 temp gauge why not just swap face plates, that's the only difference between the 37 and 39.

07-12-2012, 09:12 AM	#10
Bruce Lancaster Member Emeritus Join Date: May 2010 Location: Madison, NJ Posts: 5,230	Re: 37-39 instrument question If you are going to use tha ammeter, obviously you need to look over diagram from an ammeter equipped car, but from memory I think you will just be lengthening the big feed wire from starter solenoid (I think) to your circuit breakers so it can run through the loop. Important high amperage wire, so do good job. The former voltmeter feed would be removed leaving the remaining links that feed other gauges hooked up.