Heater Question - JeepForum.com
Reply
 
LinkBack Thread Tools
post #1 of 19 Old 11-13-2019, 08:53 PM Thread Starter
ottoman89
Registered User
 
Join Date: Apr 2016
Posts: 20
Heater Question

I have a 2002 with the 4.7 and I recently replaced the thermostat which caused my engine temp issues (surprisingly enough was easy for me to do myself). And now I'm having an issue with my heat. It's getting cold here in Iowa and I'll go out, start my Jeep and let it warm up for awhile, go back out see my engine is warm and gauge is where it should be. However, the air inside is still blowing cold air..
but as soon as I accelerate and get going, the air turns warm as it should.

Anyone else have this issue? The heater works great when I get going. And when I stop at stop signs, it stays warm.

Thanks!

ottoman89 is offline  
Sponsored Links
Advertisement
 
post #2 of 19 Old 11-13-2019, 09:52 PM
SoCal2004wj
Registered User
 
SoCal2004wj's Avatar
2004 WJ 
 
Join Date: Sep 2017
Location: Orange County, CA
Posts: 135
Question, did you "burp" the coolant system after it was refilled? Sounds like you have some air trapped inside.
SoCal2004wj is offline  
post #3 of 19 Old 11-13-2019, 10:07 PM
Mattyjm
Web Wheeler
 
Mattyjm's Avatar
2004 WJ 
 
Join Date: Dec 2014
Location: Butler, PA
Posts: 2,162
Garage
You have air in the system for sure. Bleeding the air out of a 4.7L V8 coolant system is a procedure that I am only vaguely familiar with and not an expert. I know from your post that burping the system properly and thoroughly will get your desired result.

2004 Special Edition WJ. LOADED!
2004 Rocky Mountain Edition. Froggy Bandit. Wife's Daily Driver. PRISTINE! Stock height and may stay that way.....
Mattyjm is offline  
 
post #4 of 19 Old 11-13-2019, 11:00 PM
2oldjeeps
Registered User
2000 XJ Cherokee 
 
Join Date: Aug 2017
Posts: 1,391
jfwiw my4.0 probably the same heater. the air burns my fingers on the wheel!, so it CAN make lots of heat.
and ive never burped any car i ever owned, currently 4 jeeps.
i do flush cores fully...

99wj,143,000 miles
00xj,177,000 miles
10hummer3,74,000 miles
98xj,130,000 miles
2oldjeeps is offline  
post #5 of 19 Old 11-14-2019, 08:14 AM Thread Starter
ottoman89
Registered User
 
Join Date: Apr 2016
Posts: 20
Quote:
Originally Posted by SoCal2004wj View Post
Question, did you "burp" the coolant system after it was refilled? Sounds like you have some air trapped inside.
If you mean bleed the system by "burp" it I did that. When I refilled the coolant I took the bleeder off until the coolant came out the bleeder hole. Unless there's a other way I need to do it?
ottoman89 is offline  
post #6 of 19 Old 11-14-2019, 08:16 AM Thread Starter
ottoman89
Registered User
 
Join Date: Apr 2016
Posts: 20
Quote:
Originally Posted by Mattyjm View Post
You have air in the system for sure. Bleeding the air out of a 4.7L V8 coolant system is a procedure that I am only vaguely familiar with and not an expert. I know from your post that burping the system properly and thoroughly will get your desired result.
Do I take the bleed screw back off and add more coolant as I did when I refilled it? I don't have any leaks around the thermostat so I'm not sure air could even get it unless I didn't correctly burp it.
ottoman89 is offline  
post #7 of 19 Old 11-14-2019, 03:04 PM
xcaliber81
Registered User
 
xcaliber81's Avatar
2004 WJ 
 
Join Date: Jul 2012
Location: Prince George
Posts: 4,817
What I did was added coolant until it came out the bleed hole I did this running with the heat on full and rev it up a touch you'll start to see it suck down the bleed hole and bubbles should come out if there was any.
xcaliber81 is online now  
post #8 of 19 Old 11-14-2019, 03:15 PM
AVR2
Web Wheeler
2002 WJ 
 
Join Date: Apr 2007
Location: UK
Posts: 4,362
The cooling system is designed to self-bleed over the course of about 3 drive cycles, as long as you follow the factory coolant filling procedure.

The factory refilling process is to fill through the bleed hole until the coolant starts coming out of the hole, then fill through the rad neck until full, and finally the coolant reservoir. Then just drive the Jeep, and check the coolant level in the rad and the reservoir for the first three drive cycles, refilling as necessary. This has always worked perfectly for me.
AVR2 is offline  
post #9 of 19 Old 11-14-2019, 03:18 PM
AVR2
Web Wheeler
2002 WJ 
 
Join Date: Apr 2007
Location: UK
Posts: 4,362
Quote:
Originally Posted by xcaliber81 View Post
What I did was added coolant until it came out the bleed hole I did this running with the heat on full
Just FYI, turning the heater on full does nothing to help bleed the cooling system on the WJ as there is no heater valve. The heater core always gets 100% coolant flow at all times, it's the air doors inside the HVAC box that determine whether you get hot or cold air inside the cabin.
AVR2 is offline  
post #10 of 19 Old 11-14-2019, 08:04 PM Thread Starter
ottoman89
Registered User
 
Join Date: Apr 2016
Posts: 20
Quote:
Originally Posted by AVR2 View Post
The cooling system is designed to self-bleed over the course of about 3 drive cycles, as long as you follow the factory coolant filling procedure.

The factory refilling process is to fill through the bleed hole until the coolant starts coming out of the hole, then fill through the rad neck until full, and finally the coolant reservoir. Then just drive the Jeep, and check the coolant level in the rad and the reservoir for the first three drive cycles, refilling as necessary. This has always worked perfectly for me.
Fill through the bleed hole until coolant comes out. After it comes out the bleed hole while filling through the bleed hole, you then take the radiator cap off and fill it there?
ottoman89 is offline  
post #11 of 19 Old 11-14-2019, 09:24 PM
SoCal2004wj
Registered User
 
SoCal2004wj's Avatar
2004 WJ 
 
Join Date: Sep 2017
Location: Orange County, CA
Posts: 135
Quote:
Originally Posted by ottoman89 View Post
Fill through the bleed hole until coolant comes out. After it comes out the bleed hole while filling through the bleed hole, you then take the radiator cap off and fill it there?
Exactly And recheck your overflow tank after a few cycles to make sure there's enough coolant.
SoCal2004wj is offline  
post #12 of 19 Old 11-15-2019, 07:46 AM
AVR2
Web Wheeler
2002 WJ 
 
Join Date: Apr 2007
Location: UK
Posts: 4,362
After draining/refilling the cooling system, it's normal to hear a rushing water sound behind the dash when you accelerate. This is caused by the trapped air passing through the heater core. It will be most noticeable on the first drive, but should diminish and have completely disappeared by the third drive cycle.

As said, just remember to check the coolant level at the rad neck and the reservoir tank after the engine has cooled on the first three drives. You'll almost definitely need to top up after the first drive, and maybe after the second, but everything should have fully bled and stabilised after the third.
AVR2 is offline  
post #13 of 19 Old 11-15-2019, 08:09 AM Thread Starter
ottoman89
Registered User
 
Join Date: Apr 2016
Posts: 20
Quote:
Originally Posted by SoCal2004wj View Post
Quote:
Originally Posted by ottoman89 View Post
Fill through the bleed hole until coolant comes out. After it comes out the bleed hole while filling through the bleed hole, you then take the radiator cap off and fill it there?
Exactly [IMG class=inlineimg]/forum/images/JeepForum_2016/smilies/tango_face_smile.png[/IMG] And recheck your overflow tank after a few cycles to make sure there's enough coolant.
Do I fill through the radiator cap opening until it is full also? And with the overflow do I leave it alone until i recheck it later?
ottoman89 is offline  
post #14 of 19 Old 11-15-2019, 09:09 AM
99wjtx
Registered User
 
99wjtx's Avatar
2001 WJ 
 
Join Date: Aug 2017
Posts: 511
I usually do the bleeder screw twice and don't bother with topping off the radiator.

Rage! Rage against the dying of the Jeep.

99 WJ Limited 4.7/NP242
01 WJ Laredo 4.7/NP242
99wjtx is offline  
post #15 of 19 Old 11-15-2019, 09:50 AM
JGCJeep
Registered User
2001 WJ 
 
Join Date: Jan 2019
Posts: 197
Sounds to me like it could be a vacuum issue. Do the doors that send heat to the cabin use engine vacuum to actuate?
JGCJeep is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the JeepForum.com forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid e-mail address for yourself.



Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome