My tricky temp gauge/carb issue

[JMett]

I understand that there is no computer etc ... on my 72 F-250, 360 2-bbl. However ... I have temp gauge that only likes to work when it wants to (usually after getting it warm, running into the store, and then starting it back up) and when the gauge is reading correctly, it runs 10X better and doesn't choke out when I hit the gas from a dead stop. Once the gauge has stopped working again, its back to running rough. Is this a coincidence, or is the temp gauge somehow controlling air/fuel mixture?

[DuckRyder]

The gauge is not controlling the mixture, however some 1972 trucks had a system that limited timing based on engine tempature. I thought the higher GVWR trucks did not have it though.

http://www.fordification.com/tech/image ... /trs04.jpg

If that system is either not present or is working properly, I would start looking for a short in the wiring possibly between the sender wire and the coil feed wire.

[cep62]

after getting it warm, running into the store, and then starting it back up

Maybe the ignition switch?
If it's not making a good contact the accessories and the ign isn't getting proper voltage , and by shutting it off and restarting it gets a better contact. ?
Does the switch feel loose ? or could there be dirt in the switch part under the dash ?
Another thing , how are the battery grounds? Is there good contact to the engine and to the cab?

Or in a totally different direction maybe your thermostat isn't working right and by driving and stopping at the store the heat soaks in, and these engines run better warm.

Maybe with some more info we can get closer to the problem ?

[JMett]

Thanks guys, I appreciate it! Hopefully the weather will let-up soon and I can get out there for some troubleshooting. Thanks again!

[cdeal28078]

Or in a totally different direction maybe your thermostat isn't working right and by driving and stopping at the store the heat soaks in, and these engines run better warm.

Maybe with some more info we can get closer to the problem ?[/quote]

That is what I was thinking. Where are you located? Sometimes and engine that doesn't have all of the stock air breather and hoses still on it has a problem with carb icing. The carburetor will actually freeze up inside the venturas causing the engine to run very rich, smoke and just act up. You shut the engine down for a few minutes and the built up heat in the engine migrates upwards and warms the carb thawing the trouble.
clint