: 99 Deville Northstar Overheating -wanting non contradicting answers



taylor7780
01-28-08, 04:07 PM
After reading all the posts just like mine I am still thrown in a loop.
We have pressure backing up into the surge tank -
neither of the fans are kicking on till about 230 degrees -
when we take the garden hose and push cold water thru the radiator the engine will then cool down - hook it back up to the radiator and we overheat. There was some stop leak gummed up in the hoses, thats been flushed out - My oil is not milky looking -
I think that is the summed up version and covers it all. I have replaced the water pump, thermostat and belt. So it could be the radiator - Head Gaskets - or the fans that are not kicking on - there are so many contradicting answers and of course the easiest is replace all of it - but who has the money to do all that!!??!! Was it the radiator and fans originally which now have also made it into the Head Gaskets - yikes... Oh and yes I'm a girl trying to do all this before getting taken advantage of by the Cadi dealership thats cost $4000 for new head gaskets - I can replace the whole engine for that! thanks so much for your time!!

CadillacSTS42005
01-28-08, 04:19 PM
no mily oil doesnt mean crap the N* doesnt bleed into the engine but out the pipes...

if you have pressure in the coolant you have bad headgaskets its that simple get a leak down test and a coolant exhaust gas byproduct test done

thats the ONLY way to know for sure

Submariner409
01-28-08, 06:40 PM
When the engine is at operating temperature it is normal to have 16 PSI in the surge tank (and the radiator hoses will be hard). That is the rating on the sticker on your surge tank cap. Pressurized coolant boils at a higher temp than 212F.

Did you accurately measure the fan ON temp? They, or one, normally won't come on until around 224-226 unless the A/C system is on or in defrost, when one fan runs all the time. Fans go to high at 234. (The temps may not be exact, but are within a few degrees, and things feel HOT when they finally come on.)

If you did in fact blow out a glob of snot from a coolant hose, you may "only" have coolant circulation problems which would be corrected by cleaning and flushing of hoses and the radiator.

A test kit for locating exhaust gas in the (proper mix) coolant may be found at the larger auto parts stores. That's about the only sure way to rule out head gaskets as the overheating cause. Does the system lose any coolant when running ? Is there steam or white "smoke" coming from the exhaust?

JC316
01-28-08, 07:35 PM
:yeah:

You probably just have a clogged up radiator. The fans kick on at 225*F or with the AC on.

Ranger
01-28-08, 07:42 PM
Check the purge line Taylor. If you can change a thermostat, this is a piece of cake.

Rafterd
02-12-08, 10:36 PM
[/QUOTE]A test kit for locating exhaust gas in the (proper mix) coolant may be found at the larger auto parts stores. That's about the only sure way to rule out head gaskets as the overheating cause. Does the system lose any coolant when running ? Is there steam or white "smoke" coming from the exhaust?[/QUOTE]

Where can you find these test kits? No one knows what I am asking for.

Bill

zonie77
02-12-08, 11:03 PM
You have to go to a "real" parts store. NAPA or a good independent.

Submariner409
02-13-08, 10:43 AM
taylor7780 ????????? Helllloooooo!!! Return to sender.................