coolant fill

[Missouri Rodder]

I continue to have concern with coolant fill. Although perfectly stock, my radiator cap coolant level is below much of my upper radiator hose since my radiator hose routes up around alternator and into water neck turned up. I cannot keep coolant in this hose? When i fill the system as best i can, it just discharges all coolant below the radiator cap into the overflow tank and onto the ground. I understood that you are supposed to get all of the air out of the coolant system but is that not true on these fox bodied mustangs? If so, what is the secret?

 

[madspeed]

my upper hose seems to be empty too. No cooling ir other issues here. Whats the problem?

 

[Missouri Rodder]

my upper hose seems to be empty too. No cooling ir other issues here. Whats the problem?

I thought we are supposed to get all the air out of the coolant system. I do have an occasional spike in temperature and have a coolant tank that is normally empty, radiator is always full. I can't keep the overflow tank at midlevel, but it does not leak and i keep engine bay clean so i'm not spraying any. I tried to fill after a coolant change and continue have concerns that i'm doing something wrong. as you say, no real issues, just perplexed that this is not discussed more if this would be a normal thing.

 

[RacEoHolic330]

The coolant is pumped from the bottom of the raditor and returns back to the top out of the filler neck and into the top of the radiator. The whole idea of not having air in the system applies only to the passages inside the block. Air pockets can develop in those passeges, which can cause overheating because there is not enough fluid in the system. A cooling system does not operate like a brake system, which will not work properly with the smallest amount of air in the system. You don't 'bleed' a cooling system. It's not hydraulic. There needs to be some air space in the top of the radiator because the whole system operates under the same principle as a pressure cooker to raise the boiling point of water. You don't fill the system with coolant via the upper radiator hose. You fill it through the...you guessed it...filler hole in the radiator.

Have you replaced your filler cap recently? That regulates the pressure of the system. If you are losing coolant, you may have other issues.

 

[madspeed]

well said. If you are losing coolant but not leaking it, you likely have other problems you are not yet aware of

 

[ratio411]

As long as the highest point in the system is the middle of the outbound (pressure) hose, and the air is trapped there, it can do no harm.

Newer cars need to be bled/burped usually because low hoods put the top of the radiator lower than parts of the engine itself, and/or the top radator hose is the inbound hose, and therefore will push air into the engine to get trapped.

The lower hose is your inbound (suction) hose. Make sure it is firm and/or has a support spring inside. It can suck shut if it gets soft, depriving your engine of cool water flow.

 

[Missouri Rodder]

excellent response. that's exactly what i wanted to hear. I will sleep a lot better now.

 

[madspeed]

When i fill the system as best i can, it just discharges all coolant below the radiator cap into the overflow tank and onto the ground.

??