Losing coolant from the radiator cap

[05LS8ute]

Hi I have an 05 Ls8.. started having issues in july with it overheating. replaced the thermostat and housing. after bleeding the system everything was good until a couple weeks ago..came outside and a puddle of coolant next to the driver side front tire. I have read enough on this forum to figure out I probably had a bad degas bottle. So I ordered the Dorman part and put it on..everything seemed ok for a couple of days..now I am losing coolant from my radiator cap. It was doing this same thing after replacing the t-stat and housing until it was bled of air. Problem is I didnt do the work, My sisters bf did it because I had a pretty sever broken hand and was in and out of the hospital at that time for a few weeks. Well here I am again about to have another surgery on my hand and trying to figure out what the hell is going on with this radiator cap. My hand is still broken, so I have very limited ability in turning a wrench at the moment..otherwise I am fairly technically inclined. Can anyone explain the bleed procedure to me in detail as to when I can or cannot open the degas bottle to add coolant throughout the process?? Really needing some help right now.

 

[joegr]

.... So I ordered the Dorman part and put it on..everything seemed ok for a couple of days..now I am losing coolant from my radiator cap. ...

This is a common problem/complaint with the Dorman bottle. You need to replace it with the Motorcraft one. You also need to replace all the other plastic parts of the cooling system that you did not replace. Almost everyone fights this, but almost all learn that all the plastic degrades at the same time, so do it once, or do it every week or two for months till you have it all. All at once is cheaper in the long run.
GenII LS8 Cooling System Overhaul

You have to fill and bleed exactly as directed.
2006 Lincoln LS Workshop Manual

 

[05LS8ute]

This is a common problem/complaint with the Dorman bottle. You need to replace it with the Motorcraft one. You also need to replace all the other plastic parts of the cooling system that you did not replace. Almost everyone fights this, but almost all learn that all the plastic degrades at the same time, so do it once, or do it every week or two for months till you have it all. All at once is cheaper in the long run.
GenII LS8 Cooling System Overhaul

You have to fill and bleed exactly as directed.
2006 Lincoln LS Workshop Manual

Ok I understand but why am I losing coolant from the engine fill/radiator cap?

 

[joegr]

Ok I understand but why am I losing coolant from the engine fill/radiator cap?

Because the Dorman bottle is crap and the threads on it aren't good enough to hold the cap on tight to seal it.

You don't have to wait for my replies on all this. Just actually search this site.

 

[05LS8ute]

Because the Dorman bottle is crap and the threads on it aren't good enough to hold the cap on tight to seal it.

Im talking about the front radiator main fill cap that the t-stat housing is connected to...Im not leaking anymore from the degas bottle

 

[joegr]

Im talking about the front radiator main fill cap that the t-stat housing is connected to...Im not leaking anymore from the degas bottle

Well, if you had used the correct term... (That's the engine fill cap.)

As I said before, "all the plastic degrades at the same time." There's no pressure relief or vent there. If coolant is coming out there, then something (the plastic) is broken, plain and simple.
Need to do it all: GenII LS8 Cooling System Overhaul

 

[SteveOwens]

Hi I have an 05 Ls8.. started having issues in july with it overheating. replaced the thermostat and housing. after bleeding the system everything was good until a couple weeks ago..came outside and a puddle of coolant next to the driver side front tire. I have read enough on this forum to figure out I probably had a bad degas bottle. So I ordered the Dorman part and put it on..everything seemed ok for a couple of days..now I am losing coolant from my radiator cap. It was doing this same thing after replacing the t-stat and housing until it was bled of air. Problem is I didnt do the work, My sisters bf did it because I had a pretty sever broken hand and was in and out of the hospital at that time for a few weeks. Well here I am again about to have another surgery on my hand and trying to figure out what the hell is going on with this radiator cap. My hand is still broken, so I have very limited ability in turning a wrench at the moment..otherwise I am fairly technically inclined. Can anyone explain the bleed procedure to me in detail as to when I can or cannot open the degas bottle to add coolant throughout the process?? Really needing some help right now.

You have air in the cooling system that is in the engine and there is a bleed port that is located near the brake cylinder. It has a slot for a flat blade screw driver to remove a seal screw. This bleed port will evacuate the air in the engine. To bleed the coling system which may take four or five attempts of filling the degas tank and staring up the engine to deplete the air with coolant. Do not drive the car till all air is out of the cooling system or you will overheat and if you continue the computer will not let you start the car till it cools down. Notice the front engine plastic plimbing that connecting to the radiator is all on top of the cooling system. The air must be deplaced thru the top of this plastic plumbing. when you rid the system of air squeeze the passenger side hose. It will be less stiff as before it had lots of air in the system when the cap is on. I plumbed the bleed line back into the degas by a 1/16-27 NPT 1/8" hose fitting. This allowed a simple twist of the cap to evacuate the air. While you are in fix mode replace the throttle body to center engine block hose. It is a leak that drips on the driver side rear engine location. Good Luck

 

[joegr]

You have air in the cooling system that is in the engine and there is a bleed port that is located near the brake cylinder. It has a slot for a flat blade screw driver to remove a seal screw. This bleed port will evacuate the air in the engine. To bleed the coling system which may take four or five attempts of filling the degas tank and staring up the engine to deplete the air with coolant. Do not drive the car till all air is out of the cooling system or you will overheat and if you continue the computer will not let you start the car till it cools down. Notice the front engine plastic plimbing that connecting to the radiator is all on top of the cooling system. The air must be deplaced thru the top of this plastic plumbing. when you rid the system of air squeeze the passenger side hose. It will be less stiff as before it had lots of air in the system when the cap is on. I plumbed the bleed line back into the degas by a 1/16-27 NPT 1/8" hose fitting. This allowed a simple twist of the cap to evacuate the air. While you are in fix mode replace the throttle body to center engine block hose. It is a leak that drips on the driver side rear engine location. Good Luck

Bad advice. You really must follow the correct bleeding procedure.
No amount of air in the system will cause coolant to come out at the engine fill, unless the plastic there is cracked or the seal on the fill cap is bad! (Note that while he said "radiator cap" which is the degas cap and will vent coolant when things are wrong, he really meant the engine fill cap, which does not vent.)