Head gasket??

lincoln_zero

lincoln_zero

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So my 05 LS had overheat issues.

I took everyone's advice and had the whole plastic of the cooling system replaced by a family mechanic. He called me today to tell me that after replacing the parts, and flushing the system (also removing any debree lodged in the thermostat) the coolant is travelling smoothly. However the car is still overheating.

He's suggesting to replace the thermostat at this point. Head Gasket is last resort......

Anyone have extra advice on this? Thanks...
 
everything i've read is that when you do the plastic parts, also replace the t-stat as well as intake manifold gaskets.
 
Due to the failsafe cooling feature of the engine/PCM, the odds that you have a "head gasket" problem are very very low. Can you list off exactly which parts were replaced? (Maybe he missed one? I would have thought the thermostat would have been replaced when this was done, for example.) Were all Motorcraft parts used, or was some of it aftermarket?
Did he fill and bleed it by the book? (Or was it "I know what I'm doing, I don't need the factory book for that.")

On cars that do have "head gasket" failures, it's usually that the head warped. A new gasket may fix it for a while, but really the head (and probably the block) needs to be replaced.
 
Ok so I called the mechanic and asked those questions.

He said he didn't replace any parts Yet, he just pulled it apart and looked at the plastic pieces and agree's they need replacing. I misunderstood him on the first call.
He said the pump is flowing, so thats good. He said he already ordered OEM Thermostat, and will call me once that's installed and he's assessed the issue.

This guy does things by the book. So I hope its a thermostat. I've read that the thermostat can get stuck open.
 
lincoln_zero said:
I've read that the thermostat can get stuck open.
Click to expand...

yeah, it can happen, however not very often in the LS world...

BUT, if the thermostat is stuck open, then you would have no restriction in the coolant flow (at least from the T-stat) and then should have no problem keeping the engine cool. the symptom you would see from that specific problem would be the exact opposite problem, the engine would take a lot longer to reach the proper operation temp. You also probably wouldn't get much heat from the heater either...

now on the other hand, if your thermostat was stuck closed... but that is very easy to test, put a pot of watter on the stove and set it to boil with the T-stat in it (and in the case oif this car, the T-stat housing to hold it together and then watch for it to open.
https://www.youtube.com/watch?v=aa1yG-fntRk





but that would be like building your house in SoCal right on the San Andreas Fault and only being worried about getting tornado insurance to protect your investment.
odds have it, your problem is like 87% of the rest of LSes, and your worn out plastics are to blame.
 
Update

So the repair is done. My mechanic told me the thermostat exploded when he opened up the housing.
All plastics, including thermostat, housing etc.. were replaced with motocraft OEM parts from the Ford dealer.

The bill came to $842 CAD.

So I got the car back. Its not overheating anymore. But once the temp gauge reaches half, the fan kicks in high speed. Is there still an issue? More specifically, in warm weather is it normal the fan is running so high when driving?
 
lincoln_zero said:
My mechanic told me the thermostat exploded when he opened up the housing.
Click to expand...

once those plastic parts fail, since the T-stat in this car is not a one piece part but a bunch of parts that the housing holds together, this seems to be the common way that the T-stat houses fails.


lincoln_zero said:
So I got the car back. Its not overheating anymore. But once the temp gauge reaches half, the fan kicks in high speed. Is there still an issue? More specifically, in warm weather is it normal the fan is running so high when driving?
Click to expand...

no, it is still overheating, the car is technically overheating a little bit before the gauge begins to move above the normal position, there is still a problem, most likely either all of the pieces were not replaced and there is still a leak somewhere in the system, or it may not have been bled properly.

I would also check to make sure that there is not a lot of garbage blocking air flow through the radiator, one common overlooked plastic part of the cooling system that has seem to been popping up a lot more lately is the radiator itself. normally that is not one of the plastic parts that is recommended to be replaced with the rest, but htere have definitely been an increase of members having problems with theirs.


if working properly, the fan definitely shouldn't be running on high when driving down the road and there should be enough air flow through the rad to keep the engine cool.
 
Surface grind the head on a precision grinder and no block will be needed. Many shops can do it
 
lincoln_zero said:
... Its not overheating anymore. But once the temp gauge reaches half, the fan kicks in high speed. ...
Click to expand...

Sorry, it is still overheating, just not as badly.
Are you sure that the new thermostat was assembled correctly (and not damaged in the process)?
 
maybe a leftover piece faulting the new tstat. or a off brand one failing? I'd confirm (or do the bleeding yourself) before too many more miles go on it.

GL
 
Mine did the same. High speed fan comes on around 228*. Ensure a factory thermostat was used. Also check the degas bottle. It usually cracks where you can't see it.
 
I saw the parts myself that were replaced. All plastics Except Degas bottle, replaced. No leaks. At least nothing I can see.

All Motocraft parts.

I haven't driven it much lately, its been parked. When I get home I will take a look at the coolant level, again, to ensure its not leaking. Regardless of a leak, I don't see how this can cause a vehicle to overheat unless, of course, I lose too much coolant. I mean, can a pinhole leak cause air to get into the system after it has been bled, AND it hasn't lost coolant yet? I may be jumping the gun, I have to make sure its leaking to begin with.

There may be a slight chance this Aluminium block is warped. It has overheated while the wife was driving, and myself. So several overheats may have done it in..
 
lincoln_zero said:
... I mean, can a pinhole leak cause air to get into the system after it has been bled, AND it hasn't lost coolant yet? ...
Click to expand...

Yes, that's exactly what happens. Note that you may lose some coolant, but not enough to be able to detect.

There are tests that can detect hydrocarbons (exhaust) in the coolant. Another check is to wait till the engine is completely cold. Loosen and retighten the degas cap. Start the engine and run at 3000 RPM for about a minute, then turn it off. Loosen the degas cap. Is there a hiss of pressure being released? If so, you may have a big problem.
 
hite337 said:
It would prbably get great gas mileage.
Click to expand...

yeah, but I would be more worried about a piston or two falling out of alignment, and once they start to move off axis, that's when the real problems start...
 
1LoudLS said:
yeah, but I would be more worried about a piston or two falling out of alignment, and once they start to move off axis, that's when the real problems start...
Click to expand...

True....and oil pressure might be a problem as well. Without having the mounting points for the oil pump and all.....
 
Replace your entire cooling system. Atleast all the plastics and hose assemblys. Then bleed the system exactly according to procedure. If you still have issues, inspect the plastic side tanks of your radiator, check for cracking and white residue.
 
joegr said:
Yes, that's exactly what happens. Note that you may lose some coolant, but not enough to be able to detect.

There are tests that can detect hydrocarbons (exhaust) in the coolant. Another check is to wait till the engine is completely cold. Loosen and retighten the degas cap. Start the engine and run at 3000 RPM for about a minute, then turn it off. Loosen the degas cap. Is there a hiss of pressure being released? If so, you may have a big problem.
Click to expand...

Well I check the coolant level, it hasn't dropped, but as you said I may not be able to detect it.

I'll try checking for a hiss tonight when I get home.
 
Degas bottle. If it is cracked above the coolant level then you won't loose any coolant, it just won't let the cooling system pressurize. The cooling system need to be able to build pressure in order for it to cool properly. Mine was doing the same thing until I replaced the degas bottle with a new ford degas bottle.
 
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