A week ago the temp. would always stay at the middle of the meter and
slowly going up when i turn up the A/C. But recently the temp. was so
high that the radiator exploded.. and we weren't even moving. i changed
the radiator but i saw that the temp. was going up really fast just
after have the car on for a few minutes. i changed the fan cluch,
seeing that it didnt fan as strongly once it started to get hot. and i
changed the termostat. but still im having the same problems. im
thinking its the water pump sending back the coolant into the radiator
preventing it from circulating. i know it cant be the temp. sending
unit since the engine really does get hot.
Any ideas what the problem is will be greatly appreciated. Thanks.
JohanB - 07 Aug 2006 05:30 GMT
Big air pocket ???
On the explorers I usually bleed the air out by pulling 1 of the heater
hoses off and fill it till it runs out of the hose.
> A week ago the temp. would always stay at the middle of the meter and
> slowly going up when i turn up the A/C. But recently the temp. was so
[quoted text clipped - 8 lines]
>
> Any ideas what the problem is will be greatly appreciated. Thanks.
ross - 08 Aug 2006 07:59 GMT
Might be a blown head gasket letting combustion chamber gases into the
cooling system.
There is a test that checks for gases in the antifreeze.
You might pull the radiator cap off, warm the engine up, make sure the
radiator is completely full, and watch for bubbles - you might actually see
them given you blew the radiator.
carbide@egine.com - 08 Aug 2006 16:57 GMT
> Might be a blown head gasket letting combustion chamber gases into the
> cooling system.
[quoted text clipped - 4 lines]
> radiator is completely full, and watch for bubbles - you might actually see
> them given you blew the radiator.
I do a variation on that which requires 2 people- start with a cold
engine, completely fill the radiator, start it up put 'er in gear but
keep your foot firmly on the brake. Rev it up slightly- maybe 1200 rpm,
enough to keep it from stalling, and load the engine by slipping the
clutch if it's a manual. If you have a blown head gasket which is
letting exhaust gasses into the coolant, you'll see bubbles escaping
from the radiator. It will look like it's boiling.
Loading the engine just makes it more clear by increasing the amount of
exhaust gas in the coolant, and it will leak when cold, so no point in
warming it up first.
-Paul
cmiles3 - 08 Aug 2006 19:34 GMT
Some possibilities:
Radiator fins plugged- grass seeds, bugs, cottonwood fluff, you name
it.
Fan clutch not working, or belt slipping (not likely from your
description.)
Thermostat stuck closed- I'd go with this first; it's an easy, cheap
fix.
Water pump impeller rusted away- I'd say this is likely too. Not as
easy and cheap as the thermostat, though.
Plugged radiator cores- try draining some coolant and see what comes
out.
Someone else suggested head gasket, but you'd have some other problems,
too.
Chuck
> A week ago the temp. would always stay at the middle of the meter and
> slowly going up when i turn up the A/C. But recently the temp. was so
[quoted text clipped - 8 lines]
>
> Any ideas what the problem is will be greatly appreciated. Thanks.
Ulysses - 12 Aug 2006 22:04 GMT
To me it seems like it's probably the water pump. If you squeeze the top
hose after the engine warms up you should be able to feel some pressure,
especially when you let go of the hose.
I also seem to recall something about air getting trapped in the radiator
which might cause lack of cooling. If you take of the radiator cap and let
it run for a while the air should come out. I don't think there is another
procedure for bleeding air from the system. A leaking head gasket can cause
bubbles in the cooling system too.
> A week ago the temp. would always stay at the middle of the meter and
> slowly going up when i turn up the A/C. But recently the temp. was so
[quoted text clipped - 8 lines]
>
> Any ideas what the problem is will be greatly appreciated. Thanks.
kc10 - 13 Aug 2006 00:08 GMT
I had the same problem that you describe, but only when the A/C was
on. Turned out to be the A/C condenser was blocked with road debris
and dirt. After a good cleaning, the temp ran back in the center even
with the A/C on and idling.
>To me it seems like it's probably the water pump. If you squeeze the top
>hose after the engine warms up you should be able to feel some pressure,
[quoted text clipped - 18 lines]
>>
>> Any ideas what the problem is will be greatly appreciated. Thanks.
John Normile - 13 Aug 2006 17:07 GMT
I solved an overheating problem on my '91 with a new radiator cap.
>To me it seems like it's probably the water pump. If you squeeze the top
>hose after the engine warms up you should be able to feel some pressure,
[quoted text clipped - 18 lines]
>>
>> Any ideas what the problem is will be greatly appreciated. Thanks.