Mechanics

RANDOM (OR NEAR RANDOM) OVERHEATING, THEN RETURNING TO NORMAL

1998 Dodge Caravan • 214,000 miles

I am having problems with overheating in my Dodge Caravan.

Problem: The temp gauge will go to halfway (which is where it normally sits) for a while but then after about 10-15 minutes (give or take 5 minutes) it will slowly (or relatively quickly) move towards hot. Sometimes it gets to hot, sometimes not and will generally stay there for a few minutes then work its way back down to normal. Today it got to hot so I pulled over and some coolant spewed out of the cap and more from the overflow container. Then after 5 minutes I checked the gauge and it had gone down to 3/4. I then started the car and made the short trip home. A couple of minutes later it was back to halfway/normal. The problem seems quite random but it does seem to be aggravated by working uphill or stuck in traffic.

The car does not appear to be losing fluid/coolant unless it gets hot and overflows. Both fans appear to be working correctly and work harder as the engine gets hotter. There does not appear to be any trace of coolant I the engine oil.

I have replaced the temperature sensor and thermostat.

Any ideas?
Avatar
DodgeinMexico
December 26, 2011.




Try bleeding the cooling system-don't work-check water pump operation if it continues do a chemical and pressure tests


Tiny
Rasmataz
Dec 26, 2011.
THE ONLY THING I COULD ADD TO THIS IS MAYBE YOUR FANS ARE WORKING INTERMITTENTLY--POSSIBLE RELAY GOING BAD

SEE MY LINK FOR SOME OTHER POSSIBILITIES

http://www.2carpros.com/questions/1992-ford-f-250-engine-overheating

KEEP US INFORMED

MERRY CHRISTMAS

THE MEDIC


Tiny
CJ MEDEVAC
Dec 26, 2011.
Rasmataz,
Can you give me an indication of where the cooling system bleed valve is? It is not shown in the owners manual (I don; t have a service manual) and I cannot seem to find an engine diagram anywhere on the net.

From what I have read, if the water pump is working, the top hose should get warm when running. Is this correct? If so, the pump is working as the top hose gets warm.

Also, should the water/coolant in the radiator be moving a lot as the car runs? Mine seems to move up and down a little but no running of liquid.

The Medic,
I can hear the fans running as soon as the car gets over half temperature and they proceed to get louder as the car gets hotter. They work constantly and consistently as the vehicle gets warmer than halfway. I will actually check them out today though.

I will check out the other solutions you provided for the Ford as well.

CHeers

DiM


Tiny
DodgeinMexico
Dec 26, 2011.
Hi all,

It's fixed. Turns out the inlet/outlet reservoir on the side of the radiator is supposed to have a divider in it which I presume is to divert the incoming water into the radiator fins and then when the water cycles back from returning at the other end it forces the water to go out the outlet pipe rather than back around the radiator. Well, this was missing so water/coolant coming into the radiator could simply go straight back out the outlet without going through the fins.

This raises questions as to where it went because it didn't even look corroded. It was simply gone. Anyway, this is Mexico! And at least we have a new thermostat and temp sensor and a compression test has revealed all is good there.

Phew! And thanks for your help!

DiM


Tiny
DodgeinMexico
Jan 6, 2012.
Hi all,

It's fixed. Turns out the inlet/outlet reservoir on the side of the radiator is supposed to have a divider in it which I presume is to divert the incoming water into the radiator fins and then when the water cycles back from returning at the other end it forces the water to go out the outlet pipe rather than back around the radiator. Well, this was missing so water/coolant coming into the radiator could simply go straight back out the outlet without going through the fins.

This raises questions as to where it went because it didn't even look corroded. It was simply gone. Anyway, this is Mexico! And at least we have a new thermostat and temp sensor and a compression test has revealed all is good there.

Phew! And thanks for your help!
AD


Tiny
DodgeinMexico
Jan 6, 2012.
DO ME A FAVOR AND SEND A FEW PICS OF THIS DIVIDER---BUT PICS THAT CAN EZily BE SORTA INTERPRETTED BY A 1ST GRADER!----IS IT REMOVABLE? OR IS IT BROKE OUT?

GOOD PICS AND POINT AT IT (I'VE POSTED 12 BEFORE) SO AS MANY AS YOU LIKE!---THIS MAY HELP US IN THE FUTURE

THE MEDIC


Tiny
CJ MEDEVAC
Jan 6, 2012.

AD