99 OBW Overheating

[John]

Hi all, need some input on an overheating issue on mom's 99 OBW 2.5L w 115K.

The car overheated the other day while driving. No visible leaks and when I
spoke to her she said she had heat from the heater. I checked the car when
I got home from work, needed about 1/2 gallon of coolant to fill the rad and
overflow tank. I started it and let it idle for a bit. No leaks or smell
of coolant. At operating temp there was no heat, then the cooling fans
kicked on and continued to run as the temp gauge kept rising. The gauge
continued to rise but there was still no heat. No visible leaks, no
appearance of coolant in the oil, no sweet smell from the tailpipe, no steam
like I've seen on other cracked heads/blocks.

So.....
No heat tells me that there is either a blockage or air bubble in the
system. How can I check for either of these?
The thermostat, if stuck closed, would force boiling coolant into the
overflow, correct? This did not happen so I'm assuming the t-stat is OK or
stuck open. Maybe I'll replace it anyway.
What happened to the 1/2 gallon of coolant that I had to replace?

The car is going to the shop Tuesday but what else should I check first?
It's snowing right now (Northeast MA) so I'll have to look tomorrow.

All ideas and input greatly appreciated,

 

[Edward Hayes]

Yes: You have not purged all the air from the engine. Remove readiator cap
when engine is cool and run intill top hose is hot. Use glove to squess the
top hose to expell air and top off as needed. Leave cap off and lett engine
dool and fill radiator and recap. Make sure overflow bottle has coolent
above full line as after several cooling cycles some coolent will be drawn
back into engine. As to where the coolent is going I suggest after you've
check all hoses and fitting on top of the engine that you remove the
undercover and check stuff downunder Including the head to block seal as
they have been known to weep coolent. ed

 

[eakins]

sounds like the typical blow headgasket. mileage is about right.
anti-freeze leaks internally & then blow out the exhaust. suden heat spike
is waht happens. look forward to a $1000-2000 bill to replace headgaskets.
sell the car.

 

[ajw]

I know this is late, but I'm new to this group.

You've figured it out by know, I'm sure, but I have a 2002 OBW and this past
summer it was overheating constantly for about three days. I finally
brought the car to the shop and for about $100.00 got a brand new temp
gauge. Mine was busted (and covered by warranty...but that's another
thing...damn forgotten warranty!).

I'm curious as to how this worked out...let us know.

Thanks,
ajw