I was wondering what the running temp should be on a stock 302. Currently when I drive down the road it is around 120. Now when I stop and turn it off the temp will get up around 200 or so then slowly cool off. I just thought the running temp would be a bit warmer. Any insight would be great.
Temperature
- Thread starter Karl Ray
- Start date
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"....stop and turn it off the temp will get up around 200 or so then slowly cool off"
This is true for all water cooled engines. The water stops moving thru the block allowing the block to add heat to that still water., plus no air flow.
At this age..., the temp. gage can be just a "guesstament". Somewhat depends on the T-stat but 180deg. is a good temp. for these engines.
You may have a lower T-stat., or gage is reading low. You can add an aft. mkt. gage -or- aim a laser temp reader at the eng. to get an accurate temp. of a completely warmed up eng.
This is true for all water cooled engines. The water stops moving thru the block allowing the block to add heat to that still water., plus no air flow.
At this age..., the temp. gage can be just a "guesstament". Somewhat depends on the T-stat but 180deg. is a good temp. for these engines.
You may have a lower T-stat., or gage is reading low. You can add an aft. mkt. gage -or- aim a laser temp reader at the eng. to get an accurate temp. of a completely warmed up eng.
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khouse
77 BRONC
I agree I just changed my thermostat on my 302 and put in a 180. The old one had the center metal *** broken off. I also had a bad radiator cap noticed it when I was circulating water through the block. The upper hose sucked completely flat. I had temps close to 210. Changed cap put in a 13psi and thermostat and its steady now around 175-185.
77bronc....what do you mean by put in a 180? Also, what does the 13psi mean/do. Sorry for my ignorance. Thanks
The 180 is the degree of the thermostat.
There is a pressure relief valve on the cap. The valve has a preset rating that allows it to take just up to a certain amount of pressure. In this case 13 psi. When you turn the cap on the filler neck of the radiator, you seal the two surfaces of the filler neck. The pressure relief valve spring is compressed against the lower seal when you lock the cap. The radiator filler neck should have an overflow tube right between the two sealing surfaces. If the pressure of the cooling system exceeds the preset rating of your cap, its pressure relief valve allows the lower seal to be lifted from its seat,then the excess pressure can squeeze through the overflow tube. Once enough pressure has been released (preset rating), the pressure relief valve is again closed by the spring.
There is a pressure relief valve on the cap. The valve has a preset rating that allows it to take just up to a certain amount of pressure. In this case 13 psi. When you turn the cap on the filler neck of the radiator, you seal the two surfaces of the filler neck. The pressure relief valve spring is compressed against the lower seal when you lock the cap. The radiator filler neck should have an overflow tube right between the two sealing surfaces. If the pressure of the cooling system exceeds the preset rating of your cap, its pressure relief valve allows the lower seal to be lifted from its seat,then the excess pressure can squeeze through the overflow tube. Once enough pressure has been released (preset rating), the pressure relief valve is again closed by the spring.
monza
New member
Karl, FYI:
The T-Stat regulates the temp at which coolant starts to circulate to the Rad for cooling.
Most folks prefer the 180(degrees) version - which means the coolant gets up to 180 before the T-Stat opens and sends coolant to the Rad.
Dont mean to be preachy - I had no clue what the T-Stat did until I took it all apart and put it back together.
What little I know I will happily share.
Monza.
>-Thanks Monza. I know my temp gauge could be off, but if my gauge only reads 120 - 170, if I had a 180 T-stat, does that mean it will never circulate? Just seems like low running temp to me. Probably just need to do what bully bob suggested and take a temp reading.
Re-reading., I think we forgot to mention grounding the sender wire to the block & see if it pegs the gage needle..(don't leave it pegged though)
If so., the gage is likely OK.
Then remove sender..., clean it with limeaway....clean the threads on the sender & in the hole...wire brush, etc.
Re-install with NO teflon, NO sealant. (it's a pipe fit)
See if that gets a better reading...
If so., the gage is likely OK.
Then remove sender..., clean it with limeaway....clean the threads on the sender & in the hole...wire brush, etc.
Re-install with NO teflon, NO sealant. (it's a pipe fit)
See if that gets a better reading...
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I did try grounding to block and it did peg. When I am running it always just seems to stay around the first mark. So After I drove it for awhile, I then shut it off....waited a bit, turned the key (Not Started) and the needle rose to say 190ish. So that made me think the gauge is definitly working. But again just thought running temp seemed low. That is an uneducated guess.
"That is an uneducated guess."
Karl., none of us have these issues down to an exact science/perfect art.
Soooo., your guess is likely as good as any. Don't hesitate asking.
Many of us have answers 'cause we've dealt with these issues more times than we care to admit... :-"
My eng. warmed slowly & ran cool 'til I took a long freeway run on a hot day....temp went beyond normal. Thermostat was stuck (& I mean frozen) open approx. 1/4 inch. New T-stat & back to normal.
T-stats can stick closed, all the way open, or anywhere in-between.
13 psi (pounds per sq. inch) is the pressure release point (for radiator cap) at which the water/coolant will move to the recovery bottle for the radiator.
BTW., if you want to clean/replace the sender (or change T-stat) ...drain the rad. down a bit to make it a little less messy.
Sneak the Wife's "meat thermometer" & tape it to the engine somewhere. You may get an approx. idea as to runn'n temps..
Karl., none of us have these issues down to an exact science/perfect art.
Soooo., your guess is likely as good as any. Don't hesitate asking.
Many of us have answers 'cause we've dealt with these issues more times than we care to admit... :-"
My eng. warmed slowly & ran cool 'til I took a long freeway run on a hot day....temp went beyond normal. Thermostat was stuck (& I mean frozen) open approx. 1/4 inch. New T-stat & back to normal.
T-stats can stick closed, all the way open, or anywhere in-between.
13 psi (pounds per sq. inch) is the pressure release point (for radiator cap) at which the water/coolant will move to the recovery bottle for the radiator.
BTW., if you want to clean/replace the sender (or change T-stat) ...drain the rad. down a bit to make it a little less messy.
Sneak the Wife's "meat thermometer" & tape it to the engine somewhere. You may get an approx. idea as to runn'n temps..
bigbluebronc
New member
I like the fail fully open thermostats they make them. Or I always have a small hole or drill one for small flow.
Thats just me!
Thats just me!
