New Heater Core gets Warm not Hot

[FamilyFunWagon]

Hello all,
So I did the dreaded heater core. But my heater is only warm not hot. I also noticed while driving it gets "warmer", but it is not hot by any means. Could this be due to an aftermarket heater core?

 

[TJ4Jim]

Hello all,
So I did the dreaded heater core. But my heater is only warm not hot. I also noticed while driving it gets "warmer", but it is not hot by any means. Could this be due to an aftermarket heater core?

If you just replaced all the coolant then I would be concerned with the system being completely vented/burped, also hold on to each heater hose and confirm both hoses are hot and not one hot and the other warm.

 

[L J]

Could this be due to an aftermarket heater core?

yes and I've seen it firsthand

 

[FamilyFunWagon]

Yeah, they do get hot. It's weird. It isn't cold air. It just is not what I'm used to from the factory heater core. And I cant find a factory heater core anywhere.

 

[FamilyFunWagon]

yes and I've seen it firsthand

Thanks. I was wondering, what the heck is going on.

 

[FamilyFunWagon]

If you just replaced all the coolant then I would be concerned with the system being completely vented/burped, also hold on to each heater hose and confirm both hoses are hot and not one hot and the other warm.

What is the best way to burp the jeep?

 

[Andy-WhiteTJ]

Put is over your shoulder and then lightly tap it's back!

 

[FamilyFunWagon]

Put is over your shoulder and then lightly tap it's back!

Ha. That took me bit to get. I was getting ready to pull it off.

 

[Andy-WhiteTJ]

Ha. That took me bit to get. I was getting ready to pull it off.

Sorry. I couldn't resist.

However, I think with time, the system should "burp" itself if the radiator cap and overflow bottle is functioning properly.

 

[DETOUR]

What is the best way to burp the jeep?

Vacuum fill the coolant

 

[TJ4Jim]

What is the best way to burp the jeep?

One of the more effective ways I have done it is to park facing uphill (I used to have a steep driveway) cap off, system and reserve bottle properly full, then let her run cap off. Many of us drill a 1/8" hole in the T-stat base ring on the high side if it's not already there, always found this very effective

 

[williambmac]

like others have said.... it sounds like you still have air in the system.

 

[FamilyFunWagon]

One of the more effective ways I have done it is to park facing uphill (I used to have a steep driveway) cap off, system and reserve bottle properly full, then let her run cap off. Many of us drill a 1/8" hole in the T-stat base ring on the high side if it's not already there, always found this very effective

Do you happen to have a picture of the hole you drill?

 

[FamilyFunWagon]

Would the radiator cap have any affect

 

[TJ4Jim]

Do you happen to have a picture of the hole you drill?

Would the radiator cap have any affect

Here is a generic pic and the cap which should be 18 lbs should not have any affect, it only maintains system pressure.