Why is coolant leaking from the upper hose connection to metal tube?

You need to go to a auto parts store or your car dealer to order a replacement upper hose. How To Find Fix Coolant Leaks

Is the hose damaged, check tension on clamp..

U must connect the coolant in hose to the coolant out hose with a u type metal hose by passing the heater core all together

see this causes and fix it. God bless you
Water pump -- A bad shaft seal will allow coolant to dribble out of the vent hole just under the water pump pulley shaft. If the water pump is a two-piece unit with a backing plate, the gasket between the housing and back cover may be leaking. The gasket or o-ring that seals the pump to the engine front cover on cover-mounted water pumps can also leak coolant. Look for stains, discoloration or liquid coolant on the outside of the water pump or engine.
Radiator -- Radiators can develop leaks around upper or loser hose connections as a result of vibration. The seams where the core is mated to the end tanks is another place where leaks frequently develop, especially on aluminum radiators with plastic end tanks. On copper/brass radiators, leaks typically occur where the cooling tubes in the core are connected or soldered to the core headers. The core itself is also vulnerable to stone damage. Internal corrosion caused by old coolant that has never been changed can also eat through the metal in the radiator, causing it to leak.
Most cooling systems today are designed to operate at 8 to 14 psi. If the radiator can't hold pressure, your engine will overheat and lose coolant.
Hoses -- Cracks, pinholes or splits in a radiator hose or heater hose will leak coolant. A hose leak will usually send a stream of hot coolant spraying out of the hose. A corroded hose connection or a loose or damaged hose clamp may also allow coolant to leak from the end of a hose. Sometimes the leak may only occur once the hose gets hot and the pinhole or crack opens up.

it the metal lines but the leak is in the hose cut the hose off get 2 hose clamps and a rubber hose big enough to slide over the metal ends hope this helps

1. drain coolant
2. remove engine cover
3. remove the 2 bolts from water hose connection (upper rad hose connecting to)
4. remove o-ring and thermostat
5. repeat in reverse order

this lower tube is coolant inlet tube to water pump..dealer part as far as i know..they will know what one it is if you describe it..fairly common part..not too bad to replace

That sounds like the heater bypass tube. On the end of the tube going into the water pump is an o-ring. Pull out the tube, clean it real good, put a new o-ring on it. Clean the hole well that it goes in. Then I will put a slight amount of silicone around the o-ring. That helps it go back together and fills any imperfections.
Hope this helps you.

you might want to look for a leaking head gasket

Hi,

Recheck the connection of the upper hose that leads to the engine side with particular attention to the lip of the metal tube. In most instances, it would be the hos not pushed in properly or a clamp that is not tightened wholly encompassing the hose. Additionally, you may want to check the thermostat housing for any cracks/leaks.

Hope this be of initial help/idea. Pls post back how things turned up or should you need additional information.

Good luck and kind regards.

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