Cooling system malfunction 94 Concorde

The coolant blew out of my 94 Concorde last week. I was down about a
gallon. Car did not overheat, but the temp gauge was nearing the red
zone. I refilled and drove home with no problem. Since then I have
not used any. I left the car running in the driveway for a half hour
with no loss. I checked with the heater on and off.

Pressure holds at 8. Cap is rated at 17. If I pressurize at 20,
fluid blows out the cap until it hits 8. BUT I did not see any fluid
by the radiator resevoir when the coolant first blew out. It was
difficult to locate any leak at night. I did spot some towards the
firewall on left center side of engine/trans.

I don't recall if I have ever replace any orig hoses. 12 years,
125,000 mi. Maybe it's time to do them all.

I don't likeself healing problems because they are potentially masking
a serious situation.

Any Ideas?

Thanks

 

If the fans turn on as designed and you don't see any other signs of an
overheating problem take a good look at the radiator cap rubber seal, if it
is cracked, missing rubber or just doesn't look right replace it.
That cap will dump coolant out under pressure if the seal is not good , once
it dumps out enough, the lite will turn on or the gauge will climb.

Glenn Beasley
Chrysler Tech

 

Well, I'd definitely get a good radiator cap. What most likely happened
is that its been slowly boiling coolant for days or weeks since the cap
would only maintain 8 PSI, and it lost the coolant as *vapor* not as
liquid, hence no obvious leak. Get a decent cap on there and then
monitor coolant level like a hawk for a while. If it continues dropping,
then you've got other problems (which wouldn't surprise given that you
say it was down a *gallon!* When you're that low on coolant, the temp
gauge can be meaningless- the engine can be melting itself but with no
coolant flowing past the sensor, it will read artifically low.) But the
older cast-iron Chrysler engines like your 94 would have are tough
mothers, and it may be fine anyway.

One thing you don't mention is which engine you have- the 3.5 is a great
engine, but it has a couple of possible coolant leak spots that the 3.3
doesn't (O-rings behind the water pump housing, corner passages of the
lower intake manifold gaskets).

 

If it is a 3.5 I would also suspect a failing water pump...... .. These like
to "lock up" intermittently before they finally quit.. I think almost every
one of these I have changed (I did say almost) was a "lock up" or getting
"tight"..

 

A new radistor cap seems to have solved the problem,

Thanks for the replies.

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