hi-

i have a '96 blazer LT. I can not find any information on how the engine coolant system works. The sort of see through coolant reservoir is empty - does that mean I have no coolant, or does the radiator still have some? I do not even know what the coolant reservoir is for, as I followed a hose coming out of it and it is connected to nothing. If it is part of the system, then I guess that would explain why I might not have any. Also, the cap on the radiator says 'never open' or something like that, but I can't read teh rest of it because it has faded. How can I check my coolant level?

I guess this post is kind of jumbled but I'm pretty lost on this. Can anyone help me out? diagrams are awesome haha.

 

The coolant reservoir is for overflow from the radiator. There should be a hose that leads from near the radiator cap to the upper port on the overflow bottle. There should always be coolant in the over flow bottle. If the hose to the radiator is disconnected, then it is possible that the coolant has evaporated.

Wait for the truck to cool down entirely and remove the radiator cap and check the coolant level in the radiator. I am expecting that it will below. Throw the radiator cap in the trash after buying a new Stant cap (with the safety release). Before installing it, make sure that the lower gasket surface in the neck of the radiator is clean of any debris that may cause a leak.

The cooling system works under pressure controlled by the radiator cap(16psi). This further increases the boiling point of the coolant to keep it in liquid form. As the coolant heats up, it expands. The radiator cap maintains the 16psi pressure by allowing the expanding coolant to overflow into the reservoir. As the coolant cools, the check valve in the radiator cap will open, pulling the coolant that had expanded back out of the reservoir and into the radiator. If the cap were to malfunction and not maintain the appropriate system pressure, the coolant could boil off, causing the coolant level to decrease and compromise the cooling ability of the system.

 

Thanks for the help! When I get out of class I'm going to go check this out. Is it completely necessary that the radiator cap I take off be thrown out? Also, it looks like someone took a poop in my overflow thing, any idea where I can buy a new one?

 

A new radiator cap is about $10... If your overflow tank is drained, then you either have a faulty cap or a leak somewhere in the system. The cap is the easiest thing to do first.

The overflow tank can be removed and cleaned. Or you could source a replacement tank (either new or used).

 

The reason Kyle said ditch the old cap is because the factory cap on the Blazers don't hold a good seal worth a darn and you need a good, tight seal to keep the outside air out and the pressure inside the radiator at the proper level.

 

Air + Coolant system in Blazers = Baaaaad


Get a new cap regardless.

 

The cooling system includes the following components:
[*]A radiator and coolant recovery sub-system[*]Cooling fans[*]Thermostat and housing[*]Coolant pump[*]Accessory drive belt [/ul]
Operation of the cooling system requires proper functioning of all components. Coolant is drawn from the radiator by the coolant pump and circulated through coolant jackets in the engine block, intake manifold, and cylinder head(s), and then directed back to the radiator where it is cooled.
This system directs some coolant though hoses to the heater core, to provide for heating and defrosting. A recovery reservoir is connected to the radiator to recover coolant displaced by expansion from high temperatures and maintain correct coolant level. As the coolant cools and contracts, the coolant is drawn back into the radiator by vacuum.
Cooling System Circulation
The coolant pump is belt-driven. Coolant from the radiator outlet (lower right side of the radiator) flows to the coolant pump inlet and is pumped through coolant passages in the cylinder block and into the cavities surrounding the cylinder liners. Coolant flows through holes in the cylinder head gaskets into the cylinder head coolant passages and into the throttle body coolant system. Passages in the intake manifold direct the coolant to the thermostat. When the thermostat is closed (cold engine), the coolant is prevented from retuning to the radiator and is recirculated for quick engine warm-up.
Once the engine has warmed sufficiently, the thermostat opens and coolant flows to the inlet tank on the top left side of the radiator. It is cooled as it flows across the horizontal core tubes to the outlet tanks on the right side of the radiator, completing the cycle.

 

my coolant looks semi dirty.. and my temp guage goes all the way to proper warm-up then drops back down to 160ish.. I just checked the resivoir tank today and it seems a little low.. idk wat I should do.. I had a new thermostat put in last fall thinking that was the prob..i guess not cuz the temp still drops. somebody please give me some advice to lead me in the right direction....

 

If the coolant looks dirty, I would thoroughly flush the system and see how it works afterwords. It is possible that you have some air pockets causing some difficulties in the system.

 

not trying to ***** the thread, but my over flow tank never has fluid in it and my heat doesnt ever get hot..... (ive already flushed the heater core, worked for a while now it just gets warm)... Blazer is currently not driven very often adn when it is it is less than 10 miles.. what should I do? new cap and coolant system flush??