: '96 STS OverHeating

11-27-05, 07:15 PM
This last summer I had a leak in one of the hoses in my caddy. To make a long story short I put the wrong antifreeze in the car and had to flush the system and since it was summer I didn't bother with putting the right amount of antifreeze back in the car and totally forgot as time went on. Last Wednesday night it got very cold out and Thanks Giving day I started the car and warmed it up for about the usual 15 minutes and when I got about a mile and a half I noticed the temp was running very hot but not in the danger zone. I turned around and came right home and shut the car off. Since then I've taken all the radiator hoses off and found a little bit of shush in one hose. Filled it back up with antifreeze and still no fluid seem to be getting to the motor. I've changed the thermostat, the water pump seems to be working properly and there is no Water in the Oil. Help Please... What is wrong and what can I do or have done to fix my beautiful Caddy... :crying2:

11-27-05, 08:21 PM
I have heard it said that mixing Dex & green coolant will/can cause it to coagulate. Sounds as though you have confirmed it. Drain it as well as possible and flush it til clear. Refill with a 60/40 mix as you'll never get all the water out. You should end up with close to a 50/50 mix. Ideally, a refractometer would tell you exactly what mix you have and then can be adjusted approprietly. Now that you have had the green coolant in it for several months you will be relegated to 2 yr. coolant changes as the silicated green coolant has plated the water jacket. It is irreversable.

11-27-05, 09:26 PM
With a new t-stat and the history of being out of coolant you could have a nice big air pocket in the engine.
Sometimes these can be hard to fill, especially if this happens.
You need to find a high spot in the cooling system that is attached to the engine. I can't remember the exact configuration of the '96, but look for a small coolant hose near the throttle body. Take it off and try to add more coolant. This will give the air behind the t-stat a place to go. If air is on the back side of the t-stat it will have to get freaking hot in order for it to open. Heat transfer with air or steam, doesn't work like it does when the element is immersed in coolant.
How much coolant have you added since you replaced the hoses?
Usually you should be able to fit a full gallon of coolant and close to a full gallon of water in. If you only put a gallon in my guess is that you are fighting an air pocket.

How low has this system been running?

11-27-05, 09:35 PM
Maybe the "slush" clogged the purge line.