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Engine Help diagnose random overheating??

  • Thread starter Thread starter TomOsiris
  • Start date Start date Apr 10, 2022
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General karthief

wonder how much it would cost to ship you a pair
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#21
  • Apr 12, 2022
  • #21
What is the pressure of the cap and what type of over flow tank ?
 

96pushrod

I think they're a little easier to get off
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#22
  • Apr 12, 2022
  • #22
What electric fans are you using, and what are you using to trigger them?

Just saw you answered the second part already
 

90sickfox

Wasn't a pretty sight...and I've got big hands
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#23
  • Apr 12, 2022
  • #23
This is the one I have in my car. It's mounted between master cylinder and battery using flat stock to make brackets.

A normal power steering pump might interfere with this location but I use a Volvo electric pump.
 

Cheapskate207

The left one hangs a little lower
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#24
  • Apr 12, 2022
  • #24
TomOsiris said:
No I do not, I have heard mixed things about these as far as if they actually help anything or just make it easier, I was suggested by my mechanic to let the coolant "find it's level" by overflowing but this seems to me like that would just be introducing air into the system? i.e. pushing coolant out but not pulling it back in? I may end up grabbing one of those funnels though, couldnt hurt at this point.
Thanks for you response
Click to expand...
Basically, the spill free funnel does what your mechanic recommended without making a mess. The radiator “overflows” into the funnel.
 

7991LXnSHO

wanna catch the space herp
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#25
  • Apr 12, 2022
  • #25
90sickfox said:
This is the one I have in my car. It's mounted between master cylinder and battery using flat stock to make brackets.

A normal power steering pump might interfere with this location but I use a Volvo electric pump.
Click to expand...
I like it.
I stuck with a boring stock replacement because of space.
 

TomOsiris

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#26
  • Apr 12, 2022
  • #26
General karthief said:
What is the pressure of the cap and what type of over flow tank ?
Click to expand...
stock style cap that come with SVE radiator, should I look into the Ford Racing cap or do they open at the same pressure? (thinking about swapping for fluidyne radiator this year)
SVE overflow tank, only 14 oz which I am now thinking is too small for my purposes considering the stock one is 56 oz, looking at a few replacement options now..

96pushrod said:
What electric fans are you using, and what are you using to trigger them?

Just saw you answered the second part already
Click to expand...
Mishimoto
90sickfox said:
This is the one I have in my car. It's mounted between master cylinder and battery using flat stock to make brackets.

A normal power steering pump might interfere with this location but I use a Volvo electric pump.
Click to expand...
This looks great however with my AC delete kit I wouldnt be able to fit an overflow there, it would need to be on the far side of the radiator near where the charcoal canister used to be, thanks for your response.
 

General karthief

wonder how much it would cost to ship you a pair
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#27
  • Apr 12, 2022
  • #27
The rating is on the cap
Don't understand why a stock recovery tank can't be used?
 

KRUISR

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#28
  • Apr 12, 2022
  • #28
TomOsiris said:
The fans are hooked to a sensor that threads into the port at the bottom of the radiator,
Click to expand...
Good spot for it.
 
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manicmechanic007

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#29
  • Apr 13, 2022
  • #29
Sure sounds like some air to me and once the engine is at normal operating temperature
The thermostat will still cycle if working properly but you have to watch the gauge real close to tell when open or closed
If in doubt replace the thermostat again with a Motorcraft. You want the one they hand you over the Ford dealer parts counter
Take 30 minutes to add the coolant. Keep topping it off and squeeze the upper hose and relax it to push air bubbles out
Repeat several times. Then the first time you drive it you will damn sure see the thermostat cycle
I let them cycle once and then cool down completely (watching the overflow tank) some coolant should be sucked from the tank
If it does not you got trouble with a leak somewhere
 

TomOsiris

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#30
  • Apr 13, 2022
  • #30
General karthief said:
The rating is on the cap
Don't understand why a stock recovery tank can't be used?
Click to expand...
nowhere to fit it with big dual fan shroud!
ordered a canton 56 oz and will be swapping soon!
manicmechanic007 said:
Sure sounds like some air to me and once the engine is at normal operating temperature
The thermostat will still cycle if working properly but you have to watch the gauge real close to tell when open or closed
If in doubt replace the thermostat again with a Motorcraft. You want the one they hand you over the Ford dealer parts counter
Take 30 minutes to add the coolant. Keep topping it off and squeeze the upper hose and relax it to push air bubbles out
Repeat several times. Then the first time you drive it you will damn sure see the thermostat cycle
I let them cycle once and then cool down completely (watching the overflow tank) some coolant should be sucked from the tank
If it does not you got trouble with a leak somewhere
Click to expand...
also just ordered a motorcraft 180 tstat, will be installing and going through this and all the recommended bleeding/filling procedures as soon as everything is here.
Thanks everyone for the input so far, appreciated.
 

General karthief

wonder how much it would cost to ship you a pair
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#31
  • Apr 13, 2022
  • #31
You still didn't say but the cap should be rated at 16lbs
 

manicmechanic007

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#32
  • Apr 13, 2022
  • #32
It might overheat with a 180
The T stat will be open soon and forever
As long as your radiator and fan can cool the coolant you will be okay
The idea is with a 195 the coolant circulates and cool coolant in the engine takes a few minutes to get hot
That leaves the hot coolant in the radiator long enough to cool down
So the lower temp makes the stat be open constantly and never closes
That causes the coolant to circulate constantly
Sometimes or most of the time that is insufficient. The radiator cannot cool the coolant that fast resulting in overheat
The coolant gets hotter and hotter and hotter until it overheats
Try them both
 

manicmechanic007

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#33
  • Apr 13, 2022
  • #33
You guys know right?
For every pound of pressure it raises the boiling point by 2 degrees
So with a 16 Lb. cap the coolant will not boil until 212 + 32 = 246
 
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General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,827
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polk county florida
Apr 13, 2022
#34
  • Apr 13, 2022
  • #34
manicmechanic007 said:
You guys know right?
For every pound of pressure it raises the boiling point by 2 degrees
So with a 16 Lb. cap the coolant will not boil until 212 + 32 = 246
Click to expand...
manicmechanic007 said:
It might overheat with a 180
The T stat will be open soon and forever
As long as your radiator and fan can cool the coolant you will be okay
The idea is with a 195 the coolant circulates and cool coolant in the engine takes a few minutes to get hot
That leaves the hot coolant in the radiator long enough to cool down
So the lower temp makes the stat be open constantly and never closes
That causes the coolant to circulate constantly
Sometimes or most of the time that is insufficient. The radiator cannot cool the coolant that fast resulting in overheat
The coolant gets hotter and hotter and hotter until it overheats
Try them both
Click to expand...
The 16lb cap I believe is factory recommended
And I've been running a 180* since forever in my mustang with no problems. Never getting over 200-210 in traffic and never below 190.
 
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Noobz347

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#35
  • Apr 13, 2022
  • #35
The OEM t-stat is 192*. I have not personally had an issue with the OEM t-stats, even when I was running in the high desert.

I swapped to a 180* t-stat when I installed the Kenne Bell because I [wanted] the t-stat to open earlier and remain open longer (even though the heat soak is [nothing] like interwebz wannabeez would have you believe but that is another topic).

Take that for what it's worth. You get diminishing returns on lower temp t-stats and it's also possible to prevent the oil from getting hot enough to boil off any water that it has accumulated.

With a 192* thermostat, your cooling system is generally more efficient overall. I mean, the warmer your cooling system is, the more heat will transfer to the fins and ambient air with the least amount of travel.

A 180* t-stat can help to combat heat-soak and set the cooing system up ahead of time, for heat spikes from boost.

I don't know if I explained that very well. karthief will probably tell me.
 
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limp

wrap a little cheese around it and its a done
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#36
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  • #36
Problems with coolant not cooling in a radiator come more from a HI PO water pump in my research... Pushing too much or too fast through the radiator.

I have seen electric fans plug up the "air flow" in a radiator to where they cause more problems than they are worth

General, if my car was running those temps I might try a 195 in it to see if it runs a more steady temp??? ( did you get your coffee reminder?)

A friend installed a cooler t stat in his minivan family cruiser... I " believe" it had a 210 in it and he installed a 180 or 190 so his poor little V6 could run cooler.... Thing ran poorly, fuel mileage was awful.... He reinstalled a 210 ( what was correct for this vehicle) and it fixed all that was bad...
Apparently the computer was telling it to run richer as it was not " warmed up " yet with the cooler stat.....
EVERYONE on here knows more about FI then I do so don't shoot the messenger, but I wanted to share this story....
 
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limp

wrap a little cheese around it and its a done
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#37
  • Apr 13, 2022
  • #37
I had some overheating problems in my 67dodge when I was in some " car cruises " until i installed an overflow tank.... Never a problem since...
 
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Noobz347

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#38
  • Apr 13, 2022
  • #38
limp said:
Problems with coolant not cooling in a radiator come more from a HI PO water pump in my research...
Click to expand...
I have personally witnessed this at least twice. These builds had water shooting through the cooing system so fast it was leaving before it got even halfway to ambient.

The first time I ever saw this happen, we had been working on a dude's car for a couple weeks (troubleshoot/test/run/DD until next failure kind of thing) before he thought to mention the high flow water pump.
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
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#39
  • Apr 13, 2022
  • #39
limp said:
Problems with coolant not cooling in a radiator come more from a HI PO water pump in my research... Pushing too much or too fast through the radiator.

I have seen electric fans plug up the "air flow" in a radiator to where they cause more problems than they are worth

General, if my car was running those temps I might try a 195 in it to see if it runs a more steady temp??? ( did you get your coffee reminder?)

A friend installed a cooler t stat in his minivan family cruiser... I " believe" it had a 210 in it and he installed a 180 or 190 so his poor little V6 could run cooler.... Thing ran poorly, fuel mileage was awful.... He reinstalled a 210 ( what was correct for this vehicle) and it fixed all that was bad...
Apparently the computer was telling it to run richer as it was not " warmed up " yet with the cooler stat.....
EVERYONE on here knows more about FI then I do so don't shoot the messenger, but I wanted to share this story....
Click to expand...
+1 to everything in this post.


The other thing I would like to add for AeroNose guys specifically.......................dotdotdot

Do you know that little chin spoiler that comes on the car stock and almost everybody breaks and throws away? That damned thing is important. The monicker "AeroNose" has nothing at all to do with any wind tunnel test results.
 

TomOsiris

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#40
  • Apr 13, 2022
  • #40
General karthief said:
You still didn't say but the cap should be rated at 16lbs
Click to expand...
yea I will take a look if its written on the cap, however no mention of psi rating is on the item listing page
https://lmr.com/item/SVE-8005AC/sve-radiator-cap
manicmechanic007 said:
It might overheat with a 180
The T stat will be open soon and forever
As long as your radiator and fan can cool the coolant you will be okay
The idea is with a 195 the coolant circulates and cool coolant in the engine takes a few minutes to get hot
That leaves the hot coolant in the radiator long enough to cool down
So the lower temp makes the stat be open constantly and never closes
That causes the coolant to circulate constantly
Sometimes or most of the time that is insufficient. The radiator cannot cool the coolant that fast resulting in overheat
The coolant gets hotter and hotter and hotter until it overheats
Try them both
Click to expand...
The car has never overheated under normal driving conditions so there is no issue with the fan setup, tstat rating, water pump, etc.
It had an air pocket trapped at the thermostat that caused it to close and overheat, I am just trying to determine the cause of that and how to eliminate it now.
Noobz347 said:
+1 to everything in this post.


The other thing I would like to add for AeroNose guys specifically.......................dotdotdot

Do you know that little chin spoiler that comes on the car stock and almost everybody breaks and throws away? That damned thing is important. The monicker "AeroNose" has nothing at all to do with any wind tunnel test results.
Click to expand...
I still have the air dam intact, and the overheating only happened once and at idle, I have determined due to an air pocket at the thermostat.

Thanks all who replied for your help so far.
 
Reactions: manicmechanic007, General karthief and Noobz347
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