Overheating again! & replaced all plastic parts

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adamfysher

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Have a 2001 ls 3.9

Replaced all of the plastic pieces to the cooling system, the metal Jaguar thermostat holder, DCCV.

Did the full bleed/service procedure found on this site.

Drove the car around and did not have any overheating issues. Ran the airconditioning, with no problems.

As soon as I park and shut the vehicle off, It builds enough pressure to leak coolant out of the Degas bottle cap. (I have replaced the cap as well)

Any ideas out there would be appreciated.
 
I also did a pressure test. It was charged to 15psi and after three hours it would not drop below 12psi. The only leak I found was on the actual pressure tester cap. It was one of those ones from harbor freight.
 
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Then it sounds like it's overheating. Did you 100% bleed it correctly and replace all the plastic parts.
Is your fan working?
 
After bleeding out the system, it stays at 50%. Wondering what would cause the pressure to exceed 16psi after the engine is shut off.
 
adamfysher said:
After bleeding out the system, it stays at 50%. Wondering what would cause the pressure to exceed 16psi after the engine is shut off.
Click to expand...

Because it's overheating?

Sounds like aux pump, air in the cooling system, a leak, and/or a mixture of that.

Pressure testing the system won't find the cracks that happen when the system expands, I wouldn't take a pressure test too seriously.
 
Aux pump, You happen to have a part number for one? I did not change that out yet. Also, would this run after the vehicle was shut off? That is when it will overheat. It does not overheat once the bleeding procedure is done and vehicle is kept running.
 
I would only add to make sure you have at least 50% antifreeze mix and not more than 60% antifreeze to water. Jacksonville are,huh? don-ohio :)^)
 
stugots said:
Because it's overheating?

Sounds like aux pump, air in the cooling system, a leak, and/or a mixture of that.

Pressure testing the system won't find the cracks that happen when the system expands, I wouldn't take a pressure test too seriously.
Click to expand...

Two things i noticed of note you posted on this subject.

"heat at idle " i think that could be expanded to heat at any speed.
OP is in Florida and this time of year probably not about to test his heat.
knowing that an overheated engine wont produce heat thru the heating system that could be a good test.
clever of you to come up with that but being from the north where it get's cold to be expected :)

second thing is " Pressure testing the system won't find the cracks that happen when the system expands, I wouldn't take a pressure test too seriously. "

" IF " i read correct the system pressure is 16 psi ???
if i'm wrong kick me to the curb and spit on me as you correct me :)

SO,,it would seem 15 psi would expand parts enough to detect a leak.
what i go on is pressure testing plumbing in houses and small engines for seal leaks.
always a drop from initial pressure is acceptable.
as long as min press holds.

I think your "heat" comment should be checked first ..
wouldn't that indicate air in the system ??
if there is then back to your press test scenario,, dang..
BUT !!! there is a diff between press and vacuum,,when hot goes static it shrinks and sucks,,,air ??
then BOOM !! out the expansion cap ??

question,,,,what would happen if while running the cap was removed ?
would it be like a radiator cap and blow off and send you to the hospital ??

how about taking the cap off and letting it warm up ??
would coolant overflow and drain out ??

is there not a press relief someplace in the system ??
 
Harbor Freight cap is suspect. Also, did you get a new cap? Are you POSITIVE the degas is OEM and not "OEM" from a parts store; which is most likely a Doorfman.
 
roncoinc said:
Two things i noticed of note you posted on this subject.

"heat at idle " i think that could be expanded to heat at any speed.
OP is in Florida and this time of year probably not about to test his heat.
knowing that an overheated engine wont produce heat thru the heating system that could be a good test.
clever of you to come up with that but being from the north where it get's cold to be expected :)

second thing is " Pressure testing the system won't find the cracks that happen when the system expands, I wouldn't take a pressure test too seriously. "

" IF " i read correct the system pressure is 16 psi ???
if i'm wrong kick me to the curb and spit on me as you correct me :)

SO,,it would seem 15 psi would expand parts enough to detect a leak.
what i go on is pressure testing plumbing in houses and small engines for seal leaks.
always a drop from initial pressure is acceptable.
as long as min press holds.

I think your "heat" comment should be checked first ..
wouldn't that indicate air in the system ??
if there is then back to your press test scenario,, dang..
BUT !!! there is a diff between press and vacuum,,when hot goes static it shrinks and sucks,,,air ??
then BOOM !! out the expansion cap ??

question,,,,what would happen if while running the cap was removed ?
would it be like a radiator cap and blow off and send you to the hospital ??

how about taking the cap off and letting it warm up ??
would coolant overflow and drain out ??

is there not a press relief someplace in the system ??
Click to expand...

As far as I am aware, the system should be pressurized below 16psi. The degas bottle cap releases at 16. This would be your pressure relief? There is a bleed that is used for removing air bubbles when changing out your antifreeze. I made sure a steady stream came out as instructed.

Another thing that I researched is that the pressure in the system lowers the boiling point of the antifreeze. Removing the degas bottle cap during warm up would cause spill out of the degas bottle fill once the vehicle is warmed up.

I am assuming that you are just listing those questions as ones that answer themselves. ;-)

This is just very strange to me since it only overheats AFTER i shut off the engine. When I do my full 'bleed' procedure, it does not overheat. It is only after I turn the ignition off on the vehicle. Sooo Strange.
 
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LS4me said:
Harbor Freight cap is suspect. Also, did you get a new cap? Are you POSITIVE the degas is OEM and not "OEM" from a parts store; which is most likely a Doorfman.
Click to expand...

Harbor freight cap is definitely suspect, but it is only on the vehicle during a leak test. I put the Proper degas bottle pressure relief cap on the car when running it. I also tried replacing the degas bottle cap with a new one--no change. I am also positive that I have an OEM degas bottle. I bought it from Tascaparts.com http://www.tascaparts.com/lincoln/l...ator-and-components-scat/?part_name=reservoir
 
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How do you know it isn't overheating while running? (You can't go by the gauge, it's too buffered. It will only go past the half-way mark after it is very overheated. Many scan tools can read the actual temperature.) If the engine is marginally overheated, it will boil over after shutdown.

How are you certain that the fan is okay. What have you done to verify that?
 
adamfysher said:
Another thing that I researched is that the pressure in the system lowers the boiling point of the antifreeze. Removing the degas bottle cap during warm up would cause spill out of the degas bottle fill once the vehicle is warmed up.
Click to expand...

actually its the other way around, pressure raises the boiling point and makes it harder for the coolant to boil. when the system has a small leak and con not pressurize, the boiling point is lowered and you have problems with coolant boiling and more air getting trapped into the system.
 
I have not tried using a scan tool to monitor the temperature, I will tomorrow. As far as the fan working, it kicks on and off while the vehicle is running.

Right after I do a full bleed/service of the coolant system, the temperature stays just below the half way mark while the car is running. I will check out the scan tool and get a better temperature reading.
 
1LoudLS said:
actually its the other way around, pressure raises the boiling point and makes it harder for the coolant to boil. when the system has a small leak and con not pressurize, the boiling point is lowered and you have problems with coolant boiling and more air getting trapped into the system.
Click to expand...

Got me lol. Yeah, that's what i meant.
 
adamfysher said:
I have not tried using a scan tool to monitor the temperature, I will tomorrow. As far as the fan working, it kicks on and off while the vehicle is running.

Right after I do a full bleed/service of the coolant system, the temperature stays just below the half way mark while the car is running. I will check out the scan tool and get a better temperature reading.
Click to expand...

But is it kicking into high? IMHO, the hydraulic fan is suspect.
 
LS4me said:
But is it kicking into high? IMHO, the hydraulic fan is suspect.
Click to expand...

I will check it out in the morning. I am really hoping its not the hydraulic fan. I am trying to get this car fixed good enough to get some money for a down payment for a house. 3000 obo. Not looking good. lol.
 
adamfysher said:
... As far as the fan working, it kicks on and off while the vehicle is running. ...
Click to expand...

That doesn't tell you nearly enough. The PCM controls fan speed. Is it able to do so? Start the engine cold with the AC off. Turn the AC on. The fan should noticeably speed up. With the engine really hot, the fan should sound abnormally loud. It could be failure of the actuator (not uncommon), which is not too expensive to fix.
 
yeah, if your car is overheating and you fan is not spinning so loud that it sounds like your engine has been replaced by a turbine jet engine, then its probably not turning on high.
 
Was it hot out the day it dumped coolant after turning it off?

Did you pressure test the replacement cap? There may be a defect in the sealing face on the tank or cap that only shows up when your actual cap is on.

Also check the coolant/water mixture to be 50/50. Someone mentioned this but you didn't reply with the results. You may have added 50/50, but if anything was left in the system prior to fill, it will be off.

Did you replace thermostat when you did the housing? On rare occasions it can break closed.

Is there corrosion/ a clog? Did you use a cleaner/coolant flush mix after your repairs? Water pump okay?

Stugots was mentioning the aux pump; yes it does run after the car is off to provide uniform cooling and prevent boiling of the coolant in the cylinder heads etc. Mine wore out the "brushes" on the electric motor after about 7 years. (Dang, that means I likely have to replace it again within a year!)

Hite made a good thread detailing his electric fan conversion if it does turn out to be your hydraulic fan. Pretty sure its cheaper. Have you checked your fan fluid? lol

I happen come across some data logging I did with my xcal though I can't remember why I took this so I cant verify these are normal temps. It looks like you could take advantage of the dc variable fan PID
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