The Ford Barn

brandonstc · 06-24-2015, 02:22 PM

I have a 1949 ford pickup with the original flathead 6 engine. After driving about 1.5 miles, my temperature gauge goes to 3/4 of the way up. I have installed a new sending unit. When the gauge was 3/4 up, i cut the engine off and carefully took the radiator cap off. When i took the cap off, it didn't boil over and there was no steam coming out. I checked the water temperature and it was 160 degrees. I let the engine run some more and the gauge went up to 7/8 of the way up and the water temperature went up to 170 degrees. Is there some kind of adjustment on the gauge? the truck has been converted to 12V and currently does not have a thermostat. Any help would be appreciated.

Thanks,
Brandon

JSeery · 06-24-2015, 02:57 PM

What is connected to the gauge, 6v or 12v? What type of replacement sender, NOS Ford or a modern one?

51 MERC-CT · 06-24-2015, 03:10 PM

Now that you know what temperature it is at a given position on the gage keep that in mind and drive it. Look at the original gage as just a guide that does not give actual temperature readings.
If you want actual readings install a mechanical gage to operate in conjunction with the original.

brandonstc · 06-24-2015, 03:13 PM

Thanks, if there isnt an easy fix then ill just know what position is too high. The sender is NOS sender and the gauge has 12v connected to it.

JSeery · 06-24-2015, 03:18 PM

The gauge and sender are made to work with 6v and will not work correctly with 12v. Need a voltage reducer on the gauges.

waterboychuck · 06-24-2015, 05:17 PM

Sponsored Links (Register now to hide all advertisements)

Your gauge should be all the way to the right (hot) when starting and then go down once you start your engine. You will also need a voltage reducer on the gauge.

tanner · 06-24-2015, 05:37 PM

My original sending units work well with my new old stock gauge on 12 volt w/o voltage reducer. I believe the circuitry uses the current flow controlled by the varying sender resistance to mimic the gauge resistance so it works with 6 or 12 volt. It really is a clever design. Same with the fuel gauge.

Ross F-1 · 06-24-2015, 06:13 PM

Quote:

Originally Posted by tanner

My original sending units work well with my new old stock gauge on 12 volt w/o voltage reducer. I believe the circuitry uses the current flow controlled by the varying sender resistance to mimic the gauge resistance so it works with 6 or 12 volt. It really is a clever design. Same with the fuel gauge.

It may work for a while. The senders aren't "varying resistance" tho.

Step-down · 06-24-2015, 06:39 PM

6 v positive ground vs 12 v neg ground . I have done the same early and the gauge reading was scary until I added a resister .

scooder · 06-25-2015, 07:24 AM

Fit a voltage reducer to the gas and temp gauges, you need to for them to work correctly. Simple job.
Martin.

JSeery · 06-25-2015, 07:44 AM

As Ross stated, the early Ford senders/gauges do not work on a resistance, it is a current pulse system.

toby · 06-25-2015, 04:38 PM

I run a 195 degree stat in my 50 Coupe with 226 6. It runs best when hot at 195. On occasion it will go to over 110 but never has let me down for 30,000+ miles. Taking temps with an infrared gun, the hottest its been was 110.
Don't believe your gauge markings.
Make sure you do not overfill the rad. Fill it and let it puke it out-it knows where it wants to be.

06-24-2015, 02:22 PM	#1
brandonstc Member Join Date: Jan 2014 Location: Newton, Mississippi Posts: 31	1949 Ford F1 temperature gauge question. I have a 1949 ford pickup with the original flathead 6 engine. After driving about 1.5 miles, my temperature gauge goes to 3/4 of the way up. I have installed a new sending unit. When the gauge was 3/4 up, i cut the engine off and carefully took the radiator cap off. When i took the cap off, it didn't boil over and there was no steam coming out. I checked the water temperature and it was 160 degrees. I let the engine run some more and the gauge went up to 7/8 of the way up and the water temperature went up to 170 degrees. Is there some kind of adjustment on the gauge? the truck has been converted to 12V and currently does not have a thermostat. Any help would be appreciated. Thanks, Brandon

06-24-2015, 02:57 PM	#2
JSeery Member Emeritus Join Date: Nov 2012 Location: Wichita KS Posts: 16,132	Re: 1949 Ford F1 temperature gauge question. What is connected to the gauge, 6v or 12v? What type of replacement sender, NOS Ford or a modern one?

06-24-2015, 03:10 PM	#3
51 MERC-CT Senior Member Join Date: May 2010 Location: East Hartford, Ct Posts: 5,898	Re: 1949 Ford F1 temperature gauge question. Now that you know what temperature it is at a given position on the gage keep that in mind and drive it. Look at the original gage as just a guide that does not give actual temperature readings. If you want actual readings install a mechanical gage to operate in conjunction with the original. __________________ DON'T RECALL DOING SOMETHING FOR MYSELF BASED ON SOMEONE ELSE'S LIKES OR DISLIKES

06-24-2015, 03:13 PM	#4
brandonstc Member Join Date: Jan 2014 Location: Newton, Mississippi Posts: 31	Re: 1949 Ford F1 temperature gauge question. Thanks, if there isnt an easy fix then ill just know what position is too high. The sender is NOS sender and the gauge has 12v connected to it.

06-24-2015, 03:18 PM	#5
JSeery Member Emeritus Join Date: Nov 2012 Location: Wichita KS Posts: 16,132	Re: 1949 Ford F1 temperature gauge question. The gauge and sender are made to work with 6v and will not work correctly with 12v. Need a voltage reducer on the gauges.

06-24-2015, 05:17 PM	#6
waterboychuck Senior Member Join Date: Jan 2012 Location: Nine Mile Falls,WA Posts: 900	Re: 1949 Ford F1 temperature gauge question. Sponsored Links (Register now to hide all advertisements) Your gauge should be all the way to the right (hot) when starting and then go down once you start your engine. You will also need a voltage reducer on the gauge. __________________ The sign of a good craftsman is how well they cover up their mistakes.

06-24-2015, 05:37 PM	#7
tanner Member Join Date: Feb 2014 Location: Lake Norman, NC Posts: 82	Re: 1949 Ford F1 temperature gauge question. My original sending units work well with my new old stock gauge on 12 volt w/o voltage reducer. I believe the circuitry uses the current flow controlled by the varying sender resistance to mimic the gauge resistance so it works with 6 or 12 volt. It really is a clever design. Same with the fuel gauge.

06-24-2015, 06:39 PM	#9
Step-down Senior Member Join Date: May 2012 Location: Hat City (Danbury CT) Posts: 647	Re: 1949 Ford F1 temperature gauge question. 6 v positive ground vs 12 v neg ground . I have done the same early and the gauge reading was scary until I added a resister . __________________ "I can't cry as long as I know the Lord has risen "

06-25-2015, 07:24 AM	#10
scooder Senior Member Join Date: Jul 2010 Posts: 2,595	Re: 1949 Ford F1 temperature gauge question. Fit a voltage reducer to the gas and temp gauges, you need to for them to work correctly. Simple job. Martin.

06-25-2015, 07:44 AM	#11
JSeery Member Emeritus Join Date: Nov 2012 Location: Wichita KS Posts: 16,132	Re: 1949 Ford F1 temperature gauge question. As Ross stated, the early Ford senders/gauges do not work on a resistance, it is a current pulse system.

06-25-2015, 04:38 PM	#12
toby Senior Member Join Date: May 2010 Location: Racine, WI Posts: 476	Re: 1949 Ford F1 temperature gauge question. I run a 195 degree stat in my 50 Coupe with 226 6. It runs best when hot at 195. On occasion it will go to over 110 but never has let me down for 30,000+ miles. Taking temps with an infrared gun, the hottest its been was 110. Don't believe your gauge markings. Make sure you do not overfill the rad. Fill it and let it puke it out-it knows where it wants to be.