Blown head gasket, thermostat

[Ernie]

What are the symptoms of a blown head gasket? With a blown head gasket: Is the car supposed to overheat while running or when it’s idle? If the coolant reservoir is bubbling and hissing could it be this? Can a new thermostat be faulty? Could it cause the coolant reservoir to be hissing and bubbling? I have a 2001 Chrysler 300m.

 

[Ted Mittelstaedt]

What are the symptoms of a blown head gasket?

Here are the potential types of failure and their associated symptoms, not all symptoms may be present:

1) Cylinder sealing ring failure

a) power loss
b) Failure of compression test
c) failure of cylinder leakdown test
d) engine miss
e) coolant dripping/steaming out of tailpipe
f) coolant loss
g) hard starting
h) loud noise in engine compartment
i) exhaust gases in coolant
j) runs rough after initial starting

2) coolant passage to oil passage failure

a) water in oil (pull oil plug and if brown froth comes out water is in there)
b) coolant loss

3) coolant passage to outside failure

a) coolant loss
b) coolant leaking from gasket line

4) Coolant to intake manifold failure

a) check engine light for lean running on

Here are the common ways to test for a blown head gasket other than symptom observation:

1) Take sample of coolant to radiator shop and have them test it for hydrocarbons
2) Let engine sit overnight and in morning when it's cold, disconnect ignition and crank it over, then pull plugs (real fast) and check for coolant on the plug end. Or crank it over when the plug on suspect cylinder is out and see if it blows coolant.
3) Purchase chemical type block tester at a place like NAPA and use as directed
4) Using compressed shop air pressurize each cylinder one at a time and see if coolant level at rad cap rises (cold engine)
5) Run engine till hot then do compression test on each cylinder
6) Go to a shop with an exhaust gas tester (tailpipe sniffer) and when engine running have them stick the sniffer in the overflow bottle and see if it's exhaust gas present.

Good luck with it and remember if coolant has been present in the oil for any length of time (like more than a few weeks) your rod bearings are probably heading south and even if you fix the head gasket the engine may start knocking shortly afterwards.

Ted

 

[maxpower]

What are the symptoms of a blown head gasket? With a blown head
gasket: Is the car supposed to overheat while running or when it's
idle? If the coolant reservoir is bubbling and hissing could it be
this? Can a new thermostat be faulty? Could it cause the coolant
reservoir to be hissing and bubbling? I have a 2001 Chrysler 300m.

--
Posted using the http://www.autoforumz.com interface, at author's request
Articles individually checked for conformance to usenet standards
Topic URL: http://www.autoforumz.com/Chrysler-Blown-head-gasket-thermostat-ftopict138462.html
Visit Topic URL to contact author (reg. req'd). Report abuse: http://www.autoforumz.com/eform.php?p=670866

----------------------------------------------------------

----------------------------------------------------------
color]
Post what your problem is!! Is it overheating at idle?? Possible radiator
fan not turning on? Common problem on this system.
That would cause a problem as you are in traffic or idle, highway driving
would not overheat with an inop fan.

Glenn Beasley
Chrysler Tech

 

[Bill Putney]

What are the symptoms of a blown head gasket? With a blown head gasket: Is the car supposed to overheat while running or when it's idle? If the coolant reservoir is bubbling and hissing could it be this? Can a new thermostat be faulty? Could it cause the coolant reservoir to be hissing and bubbling? I have a 2001 Chrysler 300m.

--
Posted using the http://www.autoforumz.com interface, at author's request Articles individually checked for conformance to usenet standards
Topic URL:
http://www.autoforumz.com/Chrysler-Blown-head-gasket-thermostat-ftopict138462.html

Visit Topic URL to contact author (reg. req'd). Report abuse:
http://www.autoforumz.com/eform.php?p=670866

color]

Post what your problem is!! Is it overheating at idle?? Possible radiator fan not turning on? Common problem on this system. That would cause a problem as you are in traffic or idle, highway driving would not overheat with an inop fan.

Glenn Beasley
Chrysler Tech

To add to the good info. from Ted and Glenn, I would replace the pressure bottle cap (>$10) and check for the engine cooling fan operation as a first step. They both do fail. Then go from there if problem still there.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

 

[Daniel J. Stern]

What are the symptoms of a blown head gasket?

Head gaskets can fail in numerous ways. One of the most common ways, in recent-model cars, is for combustion gas under pressure to leak into the cooling system. This causes consistent overheating, bubbling/boiling of the radiator and overflow tank, and an exhaust smell detectible when sniffing the bubbling overflow tank (in fact, one diagnostic test for a blown headgasket is to place an exhaust emission test probe above the fluid level in just such a bubbling tank.)

With a blown head gasket: Is the car supposed to overheat while running or when it’s idle?

The car is never *supposed* to overheat. With a blown head gasket, it may exhibit overheating behaviour when idling or under load.

If the coolant reservoir is bubbling and hissing
could it be this?

Certainly could.

Can a new thermostat be faulty?

Certainly can.

Could it cause the
coolant reservoir to be hissing and bubbling?

Yes.

When you changed the thermostat, did you bleed the air out of the cooling system? This is a necessary step.

 

[Bill Putney]

...When you changed the thermostat, did you bleed the air out of the cooling system? This is a necessary step.

Good point, Daniel.

To the OP: That engine has a bleeder valve on top front of the engine. Looks just like a brake bleeder. Lean over the front bumper and look straight down on top front of the engine. It is recessed a little bit.

The pressure bottle steals some coolant circulation and helps remove trapped air, but the bleeder valve needs to be used initially for any large pockets. Open the bleeder valve with the engine warmed up (system pressurized). Close it when water starts coming out. Top the pressure bottle off to the full line (don't open the cap until it's cooled down again). After at least an hour of driving (not just idling), check the bleeder again, check bottle level, and top off the bottle again.

Also, when closing the bleeder, use only light torque to snug it - it doesn't get torqued hard like a bolt.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

 

[Robby2687]

In addition to what the others wrote, check your oil to see what it looks like. If it looks more like chocolate milk rather than regular dark brown motor oil, then you have coolant leaking into it. If this is happening, fix it NOW! Coolant in the oil will take out the bearings.

What are the symptoms of a blown head gasket? With a blown head gasket: Is the car supposed to overheat while running or when it's idle? If the coolant reservoir is bubbling and hissing could it be this? Can a new thermostat be faulty? Could it cause the coolant reservoir to be hissing and bubbling? I have a 2001 Chrysler 300m.

 

[Ken Pisichko]

When you changed the thermostat, did you bleed the air out of the cooling system? This is a necessary step.

When you do this it is a USEFUL modification to the thermostat to drill a small hole in the thermostat housing. This allows "air" to bleed out of the system. Dan suggests the same as Chrysler Co (and others) - to bleed the air out of the cooling system after doing several types of cooling system service. The hole-in-the-thermostat body is a "fix" that few mention, BUT it works! Period. The air bubbles simply have a way to get out of the engine block and into the rad/expansion tank part of the system and "vent" out into the atmosphere.....

Ken
Winnipeg
Canada

 

[Bill Putney]

:

When you do this it is a USEFUL modification to the thermostat to drill a small hole in the thermostat housing. This allows "air" to bleed out of the system. Dan suggests the same as Chrysler Co (and others) - to bleed the air out of the cooling system after doing several types of cooling system service. The hole-in-the-thermostat body is a "fix" that few mention, BUT it works! Period. The air bubbles simply have a way to get out of the engine block and into the rad/expansion tank part of the system and "vent" out into the atmosphere.....

Ken
Winnipeg
Canada

(1) I believe the hole is in the OEM thermostats.
(2) Based on some discussions on the 300M Club forums, the hole also serves a second purpose for racing when cylinder and head temps can rise extremely fast - the hole helps keep the temperatures from spiking, which also prevents excessive knock retard from reducing performance. Not important for street use, but FYI.

I'm getting OT relative to the OP, but trapped air aside, I believe this hole also helps with the thermostat opening a little quicker at initial warmup by letting a little water flow and communicating the cylinder & head temperatures a little quicker (might be done for emissions purposes).

For trapped air, I would think that, even in the absence of the hole, once the thermostat opened, the air would no longer be trapped. That is particularly true on the LH cars, since the thermostat is way down low on the side of the engine.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my address with the letter 'x')

 

[Daniel J. Stern]

it is a USEFUL modification to the thermostat to drill a small hole in the thermostat housing. This allows "air" to bleed out of the system. Dan suggests the same as Chrysler Co (and others) - to bleed the air out of the cooling system after doing several types of cooling system service. The hole-in-the-thermostat body is a "fix" that few mention, BUT it works!

It's also an *unnecessary* modification, because the thermostat already has such an air bleed hole. Sometimes it's on the T-stat flange, with or without a jiggle pin installed. Sometimes it's a small notch in the thermostat valve plate, which you wouldn't see if you were seizing the thermostat with one hand and going trigger-happy on an electric drill with the other.

 

[Ken Pisichko]

It's also an *unnecessary* modification, because the thermostat already has such an air bleed hole. Sometimes it's on the T-stat flange, with or without a jiggle pin installed. Sometimes it's a small notch in the thermostat valve plate, which you wouldn't see if you were seizing the thermostat with one hand and going trigger-happy on an electric drill with the other.

Yes, I suppose there are those "trigger-happy" individuals who would do exactly as you say - but probably only once ;-)

Am I right in assuming that EVERY manufacturer of thermostats makes them with bleed holes? If so, then I have had an epiphany. Thanks for that.