Froze my tail off!

[Walnut777]

As most of us know last week I tackled that beast they call a heater core in my 96 explorer. Well, tonight I needed to use the heat and it was not good. The heat on high is warm air at best. I noticed after installing the heater core that the heat wasn't as good. I didn't notice until tonight when I really needed the heat how pathetic the heat was.
With my old heater core, the heat would get extremely hot. You wouldn't even hold your hand over the vents for very long. I liked it that way.
The thermostat is only a year old and should be fine, the temp of the truck is normal.

The only thing different is the heater core.
The one I pulled out appeared to be aluminum. The one I put in looked like copper. It came from O'reily's Auto.

Could it be the antifreeze/water ratio?
Before I would just run 70% water and 30% coolant. Now, I'm running 50/50.
Could it be either of these 2 things or could it be the blend door?

 

[Willard]

Have you bleed the system? Maybe there is just so much air in there that the heat's no getting to the core.

 

[winsorcoke]

What would be a good bleed procedure?

 

[Walnut777]

I have never heard of bleeding the coolant system.

 

[Walnut777]

bump

 

[96eb96]

I have never heard of bleeding the coolant system.

Our 4.0 engines are very sensitive to air pockets. They don't have a bypass hose, it is done internally through a small casting in the metal. The owners manual says to run the engine to hot with the cap at the first stop, and see if you have to add any coolant. Then in a few cycles you should be ok.

 

[Texan01]

Yup Bleed the system and it will be much better.

I will agree though the copper cores aren't as heat friendly as the aluminum OEM one, but they will put out ~140-150 degree air at the vents.

I get to do the same thing to mine before too long.

 

[Turdle]

Try to get the radiator cap higher than the heater core. Jack the front up if needed.
Run the engine until warm,heater on, then let it cool.
Remove the radiator cap and you should get a burp of air sound,fill coolant-fill reservoir.

repeat.
I've had to do this 3 times to get all of the air burped out.

You might also check that the coolant bypass valve is fully opening.