Sponsored

Overheating… again

OP
OP
tdstuart

tdstuart

Well-Known Member
Joined
Apr 6, 2021
Threads
72
Messages
2,566
Reaction score
1,292
Location
Arizona
First Name
Triston
Vehicle(s)
2015 Mustang Gt Premium
I did it at home with the kit from harbor freight. Easy easy. Have to drain the coolant first though.
Could you post a link or the name of the kit? Thank you!
Sponsored

 
OP
OP
tdstuart

tdstuart

Well-Known Member
Joined
Apr 6, 2021
Threads
72
Messages
2,566
Reaction score
1,292
Location
Arizona
First Name
Triston
Vehicle(s)
2015 Mustang Gt Premium
I think it's just air pockets in the system. This is from the service manual, try it and see if it gets you squared up.

coyote bleed procedure.png
I tried that after first rebuilding but maybe I’ll try again after fixing the leaks.

I forgot to mention fixing the leaks seems to have helped but it just made it take longer to overheat.
 

Cory S

Well-Known Member
Joined
Dec 10, 2019
Threads
47
Messages
3,355
Reaction score
3,751
Location
Bradford, NH
First Name
Cory
Vehicle(s)
2016 Mustang GT Premium
IF it’s air pockets, try this.

1. Drain the system (close petcock after)
2. Start with a cooled down engine
3. Jack front of car up as high as possible
4. Start car
5. Slowly fill with coolant over 3-5 minutes. Usually the thermostat will open around the 4 minute mark. You should able to put in around 6-7 quarts by this time.
6. lower front half way back down while continuing to idle, and add as necessary as engine reaches full controlled operating temperature.

You should able to get around 10-11 quarts in or so this way.

This way works every time for me since 2012.
I first discovered this when my Boss 302 was doing the exact same thing. I even bought an Airlift vacuum transfer, and all that does is collapse the soft hoses really. It does work for some people occasionally.
I’ll sell you the Airlift for cheap if you want to try it.
 

Angrey

Well-Known Member
Joined
Jun 21, 2020
Threads
104
Messages
2,794
Reaction score
2,984
Location
Coral Gables
Vehicle(s)
2016 GT350
It brings up an interesting question/subject of discussion. Is there a way to identify gaskets without pulling the heads? I don't remember if they have a tab section that sticks out from the block/head seam anywhere that you could identify the type/model of gasket. I do remember in researching it that Ford loves to change and move the coolant galleys and passages so some gaskets will work on both and some will only work on specific blocks/heads.
 

Sponsored

WildHorse

N/A or GO HOME
Joined
Jun 28, 2017
Threads
270
Messages
10,297
Reaction score
8,350
Location
Home World: CLASSIFIED
First Name
Puddintane
Vehicle(s)
'17 S550
Vehicle Showcase
1
The problem IMO is that the heater hoses sit above the expansion tank. With that config it's tricky to get all the air out. But, it shouldn't cause the overheating problem the OP is taking about.

You know at what temp the fans are turning on ? You tuned ?
 

Cory S

Well-Known Member
Joined
Dec 10, 2019
Threads
47
Messages
3,355
Reaction score
3,751
Location
Bradford, NH
First Name
Cory
Vehicle(s)
2016 Mustang GT Premium
Another question.

What shows a higher sustained cylinder head temperature?

Driving consistently or sitting at idle for 5+ minutes?

If they are higher while driving, you
have a fluid flow issue.

If they are worse at extended idle, you have an airflow issue.

(Assuming there isn’t a problem with the thermostat, W/P, gaskets, etc)
 

Angrey

Well-Known Member
Joined
Jun 21, 2020
Threads
104
Messages
2,794
Reaction score
2,984
Location
Coral Gables
Vehicle(s)
2016 GT350
Another question.

What shows a higher sustained cylinder head temperature?

Driving consistently or sitting at idle for 5+ minutes?

If they are higher while driving, you
have a fluid flow issue.

If they are worse at extended idle, you have an airflow issue.

(Assuming there isn’t a problem with the thermostat, W/P, gaskets, etc)
Even at extended idle, if the fan logic is correct, the CHT's should never reach 230. Those are CHT's that should only be achieved under hard extended use.

My tuner forgot to update the fan logic so I was seeing climbing CHT's, but as soon as I turned on the A/C the temps would drop and stabilize due to the fans coming on (stop and go traffic). We fixed it and even in the FL heat stoplight to stop light with a blower and obstructions from the H/E in front of the radiator I don't see anywhere near 230 CHT in low moving conditions. IAT's are another story
 

Cory S

Well-Known Member
Joined
Dec 10, 2019
Threads
47
Messages
3,355
Reaction score
3,751
Location
Bradford, NH
First Name
Cory
Vehicle(s)
2016 Mustang GT Premium
Even at extended idle, if the fan logic is correct, the CHT's should never reach 230. Those are CHT's that should only be achieved under hard extended use.

My tuner forgot to update the fan logic so I was seeing climbing CHT's, but as soon as I turned on the A/C the temps would drop and stabilize due to the fans coming on (stop and go traffic). We fixed it and even in the FL heat stoplight to stop light with a blower and obstructions from the H/E in front of the radiator I don't see anywhere near 230 CHT in low moving conditions. IAT's are another story
Correct. Rules out airflow from fan(s) at idle as I was inferring to. :).

I have all 3 cores completely sealed together around all 4 outer perimeters. When my fan(s) come on at idle, it will try to suck a T-shirt through the grill opening. No place for air to draw/push through except through all 3 cores. Nothing out the bottom, sides or top.
 
OP
OP
tdstuart

tdstuart

Well-Known Member
Joined
Apr 6, 2021
Threads
72
Messages
2,566
Reaction score
1,292
Location
Arizona
First Name
Triston
Vehicle(s)
2015 Mustang Gt Premium
It brings up an interesting question/subject of discussion. Is there a way to identify gaskets without pulling the heads? I don't remember if they have a tab section that sticks out from the block/head seam anywhere that you could identify the type/model of gasket. I do remember in researching it that Ford loves to change and move the coolant galleys and passages so some gaskets will work on both and some will only work on specific blocks/heads.
Pretty sure they have a tan that sticks out. I thought it was the side under the intake manifold. Not sure if it has the part number.
 

Sponsored
OP
OP
tdstuart

tdstuart

Well-Known Member
Joined
Apr 6, 2021
Threads
72
Messages
2,566
Reaction score
1,292
Location
Arizona
First Name
Triston
Vehicle(s)
2015 Mustang Gt Premium
Another question.

What shows a higher sustained cylinder head temperature?

Driving consistently or sitting at idle for 5+ minutes?

If they are higher while driving, you
have a fluid flow issue.

If they are worse at extended idle, you have an airflow issue.

(Assuming there isn’t a problem with the thermostat, W/P, gaskets, etc)
The car temps increase very slowly.

So today I drove about 20 minutes to work. Had the ac lightly on. After 10 minutes the car was a 199 cht. It seemed to stabilize but then jumped 10 deg pretty rapidly. 10 min later when I was exiting the free way it was at 225 cht. It seemed to stabilize at 219 for a bit but then started climbing again.

When I left the car idling for testing it was climbing very slowly and got to like 205.
 
OP
OP
tdstuart

tdstuart

Well-Known Member
Joined
Apr 6, 2021
Threads
72
Messages
2,566
Reaction score
1,292
Location
Arizona
First Name
Triston
Vehicle(s)
2015 Mustang Gt Premium
The problem IMO is that the heater hoses sit above the expansion tank. With that config it's tricky to get all the air out. But, it shouldn't cause the overheating problem the OP is taking about.

You know at what temp the fans are turning on ? You tuned ?
Ya car is tuned. No idea if I told Lund I put a 170 thermostat in or not but I doubt it would make a difference.
 

Cory S

Well-Known Member
Joined
Dec 10, 2019
Threads
47
Messages
3,355
Reaction score
3,751
Location
Bradford, NH
First Name
Cory
Vehicle(s)
2016 Mustang GT Premium
The car temps increase very slowly.

So today I drove about 20 minutes to work. Had the ac lightly on. After 10 minutes the car was a 199 cht. It seemed to stabilize but then jumped 10 deg pretty rapidly. 10 min later when I was exiting the free way it was at 225 cht. It seemed to stabilize at 219 for a bit but then started climbing again.

When I left the car idling for testing it was climbing very slowly and got to like 205.
Well the thermostat and fan(s) are working as intended. You may just need to drive it and keep checking the coolant level every few days. It may drop randomly, meaning an air pocket has been filled, or it’s consuming it..
 

Cory S

Well-Known Member
Joined
Dec 10, 2019
Threads
47
Messages
3,355
Reaction score
3,751
Location
Bradford, NH
First Name
Cory
Vehicle(s)
2016 Mustang GT Premium
Ya car is tuned. No idea if I told Lund I put a 170 thermostat in or not but I doubt it would make a difference.
Nope. It wouldn’t. When the coolant temp is over the closing temperature, it doesn’t matter. Stock thermostat I believe is 192-195°. Which usually keeps CHT’s around 202-210°F average.
 
OP
OP
tdstuart

tdstuart

Well-Known Member
Joined
Apr 6, 2021
Threads
72
Messages
2,566
Reaction score
1,292
Location
Arizona
First Name
Triston
Vehicle(s)
2015 Mustang Gt Premium
Well the thermostat and fan(s) are working as intended. You may just need to drive it and keep checking the coolant level every few days. It may drop randomly, meaning an air pocket has been filled, or it’s consuming it..
I do also have the mmr head cooling mod. I’m wondering if air may be trapped in there.

Also I pressure tested the system again at 21 psi and it lost 1 psi of pressure after about 3.5 hours. Don’t think that’s enough to cause issues.
Sponsored

 
 








Top