Heater core

Hey all, I am having some trouble. My heater core started leaking the beginning of last winter.:mad: I bypassed the heater core so it didn't leak and blow anit-freeze steam all over my windshield (took me a week to get it totally cleaned).:headshake I don't really want to go through another winter without heat. Has anybody ever changed a heater core. I would like to know what is involved with this job before I get eye deep in a pile of s**t. Thanks.

Year make and model wo/w air?

Most heater cores take 8-12 hrs labor.

Have you looked up in the how to section?

good link here with pics:

http://www.sytyarchives.com/howto/viewarticle.php?article_name=heater_core.php&dir=climate_controls

Plan on a long day

Thank you ericn1300. I'm not sure what year that was on the post but I will definately use it as a reference. thanx. My SUV is a 2001 Oldsmobile Bravada. 4.3L Vortech V-6. I'm a real easy driver so I don't have to worry too much about 'jumping off the line' causing stress on the heater lines. I have the stuff to flush the radiator and system but I procrastinated and the heater core went out. Would that have something to do with the HC going? I'm not real great when it comes to climate control systems. I do have AC as well. I've heard, but not sure, that the heater system runs off the AC pump and certain parts of the AC system. That true? Thank you all for your time in posting and reading my crazy questions.

I've heard, but not sure, that the heater system runs off the AC pump and certain parts of the AC system.
Never heard of that, doubt that it's true. The climate control has a blend door to mix heated air with cool to your preference, but the sources remain different. The only thing I can think of that they may be talking about is that the AC does run when you turn your defroster on to dry the warm air to the inside of the windshield.

After replacing the heater core be sure to check for voltage in the coolant. Put the postive lead of a volt meter in the coolant and the negative to a body ground. Voltage should be no more than .03, anything more clean and tighten your engine grounds. Excessive voltage in the coolant will cause pin holes to form in the heater core.

Thank you so much for your help. I am going to tear into this POS this weekend. I will get back to you guys Monday. I don't have internet at home so I have to use it at work. I'm planning on a long weekend with this sucker though. Thanks again for the advice.

You are welcome and good Luck.
Search the how to section for help and a good repair book that shows what to do on it would help you a lot.
If you get the right bolts/screws and wiring unpluged,
The dash swings down and out on it.
I always drop the steering column down and out before pulling dash.
Let us know how it goes.

Thank you so much for your help. I am going to tear into this POS this weekend. I will get back to you guys Monday. I don't have internet at home so I have to use it at work. I'm planning on a long weekend with this sucker though. Thanks again for the advice.

Use the free dial-up. Might be faster than smoke signals (except for weekends :wink: )

hey ya'll. Didn't get a chance to pull the HC itself this weekend. When I'm pullin the HC, do I have to pull the entire dash, steering column, cluster, etc. etc. This is my only vehicle and I need it daily. Is there any way I can just pull the glove box and parts around it but leave the dash? I don't have to mess with the airbag or related system do I? Also, most pictures I can't access at work if they are online stored photos. Thank you all VERY much for your time.

cbec1999, the smoke signals have been kinda difficult to use anyhow. I keep burning the dang blanket. Maybe I shouldn't make the fire so hot. Anyhow, where I live (Dormitory) I can't even get the dail-up to work. This sucks! But s**t happens I guess. Thanks for the tip though.

No.No.No. Way
Only on a ford and just some of them.
Do you have them wild dreams very often?

The dash has to come out on yours..
Look around the how to section and get some good repair info to help you along with it.

On the air bag just unhook battery a hr.or more before starting on it.
On the steering column put wheels straight ahead and lock column so steering wheel does not turn.
If you turn the wheel when steering column is undone it will put a world of hurt on the SIR clock spring.

Yes I have them wild dreams all the time. That's why I ask about them before I put them into action. They get me into trouble. That really sucks. But thank you for the verification. I am going to get on this weekend. I have yet to get a new HC. Anything to look for in particular on the new HC to verify it's a good one? Should I do an fresh anti-freeze flush before or after I install the new HC? Agian, thanks for the info. It's much appreciated.

Yes I have them wild dreams all the time. That's why I ask about them before I put them into action. They get me into trouble. That really sucks. But thank you for the verification. I am going to get on this weekend. I have yet to get a new HC. Anything to look for in particular on the new HC to verify it's a good one? Should I do an fresh anti-freeze flush before or after I install the new HC? Agian, thanks for the info. It's much appreciated.

You are welcome.
Just pulling your leg on the dreams.
But always pays to check it out before hand.
I always like to flush out first before replacing heater core if system is very dirty..
On flushing they make a flush stuff you can put in it and it helps to clean out engine block and rad heater core.
You flush out old coolant and add water and flush stuff and then run a while and flush out water and flush stuff.
Then add new coolant after heater core replace.

On replacing heater core get some good repair info on how to do it.

A factory repair manual or the All Data online sub is very helpful.
http://www.alldata.com/products/diy/index.html
Let us know how it goes.
Good luck

Anybody know off hand what the dimensions would be for a 2001 Bravada HC? Anything in particular to inspect on the new HC? Thank you all for all your great input.

Anybody know off hand what the dimensions would be for a 2001 Bravada HC? Anything in particular to inspect on the new HC? Thank you all for all your great input.

When you put the hoses on the new one, put Armor-All (silicone) on the pipes. It will make them slide on easier, and prevent seizing.

The pipes will fracture easily on core bodies... USE CARE.

Thanx for the info. I'm going to pick up the new HC tonight. I will let ya'll know haw it all went down after the swap.

One tip on flushing the system. Remove the radiator hoses and flush the block out, then flush the radiator with the hoses off. This will keep all the crud from the block out of your radiator. If you're still running Dex-cool you will probably have a good amount of crud and the Dex-cool might have caused your HC to go out.

I've always heard to stick with the factory specified coolant/oil and other fluids. What would you recommend for coolant if the Dex-cool gunks up? I also have never done a flush on it and I just rolled 91,000. I have never done a flush on a road vehicle. Done them on tractors at the end of the year for winterization but never a car. What kind of pressure should I run on the block/radiator when flushing? Thanks for the info.

First, there are many threads and posts on this Forum on how to Flush your system, check the How-to section and do a search.

To answer your questions, Unless you have special equipment, you will probably only get what ever pressure you get out of your Garden Hose. I do not recommend Dex-Cool after it clogged up my system.

I suggest that you buy a bottle of Prestone Radiator flush and follow the instructions on the bottle.

It should go something like this: Drain the entire system and fill with clean water only and add the flush. Close the system and start the engine, bring it up to normal operating Temperature and let the engine run for whatever time the bottle says (usually 5-15 minutes). Drain the system and get as much of the flush/water out as you can. What I like to do is connect the garden hose directly to the heater hose that goes into the top of the engine and try to flush as much crap out as you can. Most water supply pressures run about 45-60 lbs. which is plenty good. Remove the lower radiator hose so you dont blow all of the crap into the radiator. Flush the radiator with a rag wrapped around the garden hose and wedged into the upper and lower hose ports and flush until the water runs clean. I like to flush it from the bottom up and the top down. I also disconect the heater hoses and flush the heater core too, but you ar replacing yours, so this is FYI.

Again the more of the crud you get out, the better you will be. Take your time and and don't get in a hurry. You should probably replace your T-Stat and Rad cap too. Anyway, when everything is all flushed and clean drain your system and add the antifreeze, then top off with distilled water. I think I would run plain water until after you swap out the HC, then drain and add the antifreeze.

Take a look at this thread: http://www.automotiveforums.com/vbulletin/showthread.php?t=729213

Got the HC swapped this weekend! Got it all put back together. It's working GREAT! Thank you all VERY much for your help and guidance. It took me about 18 hours to do because I've never done it. But, as I said, it's put together and working. I flushed it until it ran clear water out of the block and radiater. That to a couple of hours to get that done. There was a TON of crap in that system. That's why the old HC went out I figure. Agian, thank you all for your help.

Great Job, it is not easy. Thanks for posting back. Did you replace with Dex-Cool?

I replaced the coolant with Prestone and diluted myself with distilled water. It is a GM Dex-Cool approved coolant, but not the actual Dex-Cool. There was alot of crap that came out of the block and radiator. Thanks for the tip on Dex-Cool though.

I replaced the coolant with Prestone and diluted myself with distilled water. It is a GM Dex-Cool approved coolant, but not the actual Dex-Cool. There was alot of crap that came out of the block and radiator. Thanks for the tip on Dex-Cool though.

Again, Great Job. Enjoy your work!:naughty:

There was alot of crap that came out of the block and radiator. Thanks for the tip on Dex-Cool though.

Pinkish-brown plugs. Seen 'em on 4 dex vehicles, including an '02 1ton I bought NEW, and maintained IMMACULATELY.

Flush the dex.