300m overheating

Please help me! I just bought a 2001 Chrysler 300m and its
overheating. So far, I only noticed that its happened when it’s a low
speeds. The thing is that it goes from its average temperature
position to the redline in about 15 seconds. Weird thing is when I
re-start it and drive off, the temperature normalizes in about 10
seconds. I don’t understand what it could be. Any info would be
greatly appreciated.

Thanks!

 

With temperature gauge readings changing that quickly and repeatably on
restarting the engine, it's more likely to be a gauge problem than an
actual overheating problem.

 

What Daniel said notwithstanding, make sure the engine fans are working,
and crack the air bleeder to see if you have any trapped air. Of course
check coolant level in pressure bottle. Thermostat may be opening late
(only after a heat soak which would explain the behavior you're seeing)
- not as easy to check - thermostat located underneath the driver's side
near the front, and not easy to get to .

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

 

http://www.autoforumz.com/eform.php?p=636936

LOL it is not a gauge problem, You need to get your fans checked out, That's
a common problem with the fans on that vehicle. Also check the Cartridge
fuses in the PDC one may be blown due to a fan locking up.
Severe damage could occur if you continue to drive this vehicle while it is
running hot.

If it is the 2.7 engine have the radiator inlet connector checked for a
possible leak at the connector/bleeder screw.

Glenn Beasley
Chrysler Tech

 

You also should make sure the radiator doesen't have a bunch of
leaves and dirt and crap that is blocking the airflow.

Ted

 

Thank you all for your help! My mechanic now says I need a new
radiator, because he saw that the hoses near the radiator were
about to bust. He says that’s because the radiator is clogged. I
wonder if what Bill said could be true. I noticed that the car works
fine when running at normal speeds. But after a normal drive, when I
reach the parking lot, and sit there for a few minutes, the
temparsture gauge will climb dramatically. Does that sound like air
could be trapped? ANY info would be awesome. Thanks!!!


Ernie

 

Only thing I can add is that to conclude that the radiator is bad based
on the hoses being "about to bust" is not good. If he's saying that
*after* ruling out several other possible causes of overheating, that's
one thing (and maybe you left that out), but to see tight hoses and
conclude that the radiator is bad on that alone is not a good diagnosis.

Have you verified that the fans are coming on? Heating up when sitting
still but not when moving points in that direction, but is not proof.

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

 

Someone posted a while back a wierd overheating problem in the 300M that
could be cured by back flushing the cooling system. According to the post,
grit left over from production can sometimes work itself into holes thru
which coolant was supposed to flow and backflushing would remove it. For
what its worth.

 

http://www.autoforumz.com/eform.php?p=637765

My opinion only.
After you get the new radiator replaced dont be surprised if they comeback
with the fans needing replacing too, When the car is idling and starting to
go hot see if the fanns turn on.

 

Yes that is true, 2.7L Engine: Drain coolant. Remove thermostat housing and
thermostat located on the lower left side of the block. It may be necessary
to relocate the accessories on that side to gain access. Remove the black
plastic water outlet on the top side of the engine. Many think this is the
thermostat housing but it isn't these engines use a different theory for
regulating the coolant into the engine as compared to a 2.0 or a 2.4. With
the thermostat removed (lower left of engine) you will notice a round
machined area and a small drilled hole about the diameter of a pencil in the
cavity. Use shop air and blow air into this small hole, the air should exit
at the top of the engine on the left cylinder head water outlet. Use shop
rags to catch debris from re-entering the cooling system. You may need to
reverse this procedure and apply air from the top to dislodge stubborn
chips, mechanics wire will also help.
.. Due to the different design of the 3.5 versus the 2.7 it may be necessary
to remove the lower intake and possibly the left cylinder head to remove the
debris. There is a machined pocket in the cylinder head that can trap
material easier than on a 2.7 engine.

 

Okay, the fans are coming on. But how do I crack the air bleeder?
Where is it at? Thanks

 

Assuming you don't have the 2.7 (European M's), the bleeder is located
on top front driver's side of engine - looks exactly like a brake bleeder.

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

 

You said that "I replaced the radiator, x,x,x,x"

Are you saying that you personally did the work, or that you paid your
mechanic to replace all those things.

If you personally replaced all that and, finally admitting defeat, took your
car to your mechanic who wants to replace the head gaskets, then you
are getting a good deal.

If your mechanic replaced all that and it didn't fix the problem then
you need to stuff his $680 bill up his ass.

Ted