Chrysler 300C & SRT8 Forums banner
1 - 9 of 9 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter · #1 ·
Hi,
My 2011 Chrysler 300 keeps having Overheating problems. I've replaced the Thermostat, Water pump, Temp Sensor, Radiator, Radiator fan a few times in the last year, and it still overheats. It doesn't overheat where the needle goes all the way to the red "H" Line, but it waddles back and forth. My mechanic has run test on the head gaskets, and he says they come back fine. It doesn't leak any coolant, I've changed the thermostat 3 times in the last 3 months and the temperature is ok for about a week or two, then the temperature needle beings to waddle back and forth. It only does this when the outside temperature is Above 90 degrees. Any Idea what might be causing this?
 

·
Registered
Joined
·
1,507 Posts
Hi,
My 2011 Chrysler 300 keeps having Overheating problems. I've replaced the Thermostat, Water pump, Temp Sensor, Radiator, Radiator fan a few times in the last year, and it still overheats. It doesn't overheat where the needle goes all the way to the red "H" Line, but it waddles back and forth. My mechanic has run test on the head gaskets, and he says they come back fine. It doesn't leak any coolant, I've changed the thermostat 3 times in the last 3 months and the temperature is ok for about a week or two, then the temperature needle beings to waddle back and forth. It only does this when the outside temperature is Above 90 degrees. Any Idea what might be causing this?
No need to crosspost all over the site.

I don't know what "waddles back and forth" means, and I'm not particularly concerned with what the analog gauge does anyway, unless it climbs past the half-way mark and stays there for any length of time. What engine have you got, what thermostat did you put in, what actual coolant temps are you seeing, and exactly what coolant are you running?
 

·
Registered
Joined
·
6 Posts
Discussion Starter · #3 ·
No need to crosspost all over the site.

I don't know what "waddles back and forth" means, and I'm not particularly concerned with what the analog gauge does anyway, unless it climbs past the half-way mark and stays there for any length of time. What engine have you got, what thermostat did you put in, what actual coolant temps are you seeing, and exactly what coolant are you running?
Sorry about that. Just wanted to make sure someone would see my post and would help me out lol. What I mean by waddles back and forth, is that the needle goes past the midpoint of the Temperature gauge and then comes back. When I'm going up a hill, the needle goes all the way until the 3/4 line almost to the red and when I'm back on a straight road it cools down to normal. Coolant I'm using is the ZEREX (for use with GM/FORD/CHRYSLER)
DEX-COOL 50/50 Prediluted.
 

Attachments

·
Registered
Joined
·
1,507 Posts
DEX-COOL 50/50 Prediluted.
Dex-Cool? Good God, you may as well have poured cement in there.

What you need to do is to perform a very careful flush with distilled water. I would take the thermostat out, cut out the poppet, put it back in, and flush until you get all that crap out of there. It will be slow going using the radiator petcock, I'd probably just pull the lower radiator hose.

Once the water comes out clean, I would replace the thermostat with a new one, get some gen-yoo-wine Mopar Pink HOAT coolant concentrate, refill the radiator, and top it off with distilled water. You'll want to wind up with roughly a 50/50 mix.

If you don't want to use the Mopar stuff, find a good-quality HOAT concentrate like Motorcraft Gold or Zerex G05.

Once that <shudder> Dex-Cool is out of there, let's see what your temps look like.
 

·
Registered
Joined
·
6 Posts
Discussion Starter · #5 ·
Dex-Cool? Good God, you may has well have poured cement in there.

What you need to do is to perform a very careful flush with distilled water. I would take the thermostat out, cut out the poppet, put it back in, and flush until you get all that crap out of there. It will be slow going using the radiator petcock, I'd probably just pull the lower radiator hose.

Once the water comes out clean, I would replace the thermostat with a new one, get some gen-yoo-wine Mopar Pink HOAT coolant concentrate, refill the radiator, and top it off with distilled water. You'll want to wind up with roughly a 50/50 mix.

If you don't want to use the Mopar stuff, find a good-quality HOAT concentrate like Motorcraft Gold or Zerex G05.

Once that <shudder> Dex-Cool is out of there, let's see what your temps look like.
Cool. Thank you for all this information. I appreciate it. I will try that.
 

·
Registered
Joined
·
103 Posts
If you want to know why using Dexcool is such a no-no in vehicles that do not come from the factory with it i.e., Chryslers, Google "Deathcool". Granted it's been years since the horror of Deathcool first happened, lessons learned are NEVER mix Deathcool with anything (other than water), don't use it in older cars and pray you don't introduce air into the system.
 

·
Registered
Joined
·
1 Posts
Hi,
My 2011 Chrysler 300 keeps having Overheating problems. I've replaced the Thermostat, Water pump, Temp Sensor, Radiator, Radiator fan a few times in the last year, and it still overheats. It doesn't overheat where the needle goes all the way to the red "H" Line, but it waddles back and forth. My mechanic has run test on the head gaskets, and he says they come back fine. It doesn't leak any coolant, I've changed the thermostat 3 times in the last 3 months and the temperature is ok for about a week or two, then the temperature needle beings to waddle back and forth. It only does this when the outside temperature is Above 90 degrees. Any Idea what might be causing this?
Check your radiator fans see if they are coming on, I just replaced mine with the same issue.
 
1 - 9 of 9 Posts
Top