Coolant

[Brian AuBuchon]

I just replaced my theromstat. In doing so I drained about 1 Gallon of coolant. When finished I replaced about 3/4 of a gallon into the overflow reservoir. This coolant level is to the top it will not go back into the radiator. Can somebody tell me what I need to do to get the coolant back into the radiator.

 

[Kevin Palmer]

The system is SUPPOSE to draw it back in as it needs it based on cooling the engine.



It is not uncommon for the system to NOT take coolant from the over flow until you run it up to temp for a more than idle amount of time.



Go for a drive down the road long enough to bring it up to temp. Once the stat opens it should pull from the over-flow tank if coolant is needed.

 

[Brian AuBuchon]

I drove it 30 miles to work today and nothing changed. I'll see what happens when I drive home. I live in Dallas and it's like 95 degrees today maybe that will make a difference.

 

[Todd Z]

umm.. did you fill the radiator up through the cap first????

Fill it through the cap manually first, then let the system find it's own level..

Todd Z

 

[Brian AuBuchon]

All the instruction I could find said not to fill thru the cap.

I guess I'll try to extract what's in the overflow tank and fill it thru the Cap.

 

[Kevin Palmer]

KC,

If your going to fill thru the cap you MUST do it one of two ways...



If the engine is cold simply open the cap and fill it up.



If the engine is warm or hot, (up tp temp), the engine MUST be running when you put in the fluid.

Why,,,, If the engine is not running and it is up to temp you will be putting cold fluid into the radiator. Once you start the engine the cold fluid will suddenly reach the engine block and may crack a head or the block itself due to the extreme temp difference.



There is nothing wrong with filling it when the engine is up to temp as long as the engine is running.

 

[Fred]

Just one note. Don't open the radiator cap when the cooling system is up to temp AND under pressure. You could get scalded if the hot coolant sprays out from the pressure. Be careful. You can sort of tell if the system is under pressure by squeezing the upper radiator hose, but still, BE CAREFUL.

 

[Kevin Palmer]

Good point Fred. I guess we just know those things.



I should not assume......

 

[Fred]

Yeah. I've actually opened many hot/under pressure systems when I worked at a GM dealer. I used a cloth fender cover, wadded into a BIG ball, as an 'oven mit'. Just wanted to be sure to warn kc or whoever that may not know about the danger.