Replacing heater core

I have a 97 Grand Cherokee 6cyl with air. I need to replace the heater core (windows fog up, and can smell the sweet smell of antifreeze) and in my repair manual it says that I have to get the AC system discharged. Does any one know if I can replace the heater core without having to get that done, or is the AC system too much in the way?

Reply to
jeepwillies
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I have a 97 Grand Cherokee 6cyl with air. I need to replace the heater core (windows fog up, and can smell the sweet smell of antifreeze) and in my repair manual it says that I have to get the AC system discharged. Does any one know if I can replace the heater core without having to get that done, or is the AC system too much in the way?

Reply to
jeepwillies

Just did an evaporator on one of these.. believe it was an earlier model with the 5.2L motor. You'll have to discharge the AC.. the heater core is in the same box as the evap. Have you priced the heater core yet?.. better be sitting down. The price for the one I was working on was something in the neighborhood of $220. Just for the part.

Pain in the ass job.. remove dash and everything down to metal firewall. Plan on an entire weekend to do it.

Hope this helps..

Regards,

Jim

Reply to
Jim

Is it just me or does it seem that the heater core is actually the "core" of the car in more than one way? I swear, they start with a heater core and build the rest of the car around it. (I know not all cars are like this - they usually have some other "endearing" quality that makes up for it though...)

Ray

Reply to
Ray

Approximately 9/18/03 06:51, jeepwillies uttered for posterity:

Once you remove the dash and the defrost duct, the heater and A/C come out as a unit. I suppose it might be possible to get in there if you are a contortionist and swap only the heater core, but I'd have to see it. To remove the unit, the FSM also says to pull the refrigerant and drain the radiator. This looks like a real "fun" task.

Reply to
Lon Stowell

I just did the heater core on our 95 Mercury Tracer. What a fun job.. =o' Just like the GC, it's got the dash built on top of the heater box. I got the heater box free without taking out the dash but I couldn't get it out. The center supports held it in there like a jail cell. Once I loosened all the screws on top and side of the dash as well as remove just about everything in the center console, the whole dash came out as a unit (not anywhere light enough for one person to lift, luckily I was the only one working on it at the time..) and the heater core finally was released from its prison. Getting it back in wasn't so bad...

-Bruce

Reply to
Bruce Chang

The only car I've ever had that was NOT this way is my '49 Plymouth coupe. Optional under-dash heater :-p

To be honest, my '66 and '69 Dodges aren't TOO bad in that regard. Don't have to discharge the A/C, don't have to drain the radiator (firewall connections are above the engine so you can pull the hoses with a full radiator and the water runs back into the engine instead of out on the garage floor). But you do have to dismantle the diverter door assembly which is a bit tedious. I sincerely pray I *never* have to touch the cores on my '73 Plymouth or 93 Eagle, though. Ick.

Reply to
Steve

It's not just you :(

For a part that is a known failure item, sooner or later, they sure have a way of burying it.

psycho

Reply to
psycho_pastrami

Are you saying that the heater core and evaporator are actually one unit?

Or are you saying that they are 2 separate units, but housed in the same "duct work box" ?

For example, in my 92 Caprice, the heater core and evaporator are 2 separate units but they lie next to each other buried in the ductwork of the bottom of the dashboard.

In my particular case, you don't have to fuss with the other one to change either of them.

Still, it's a real pita!!

In the case of the Jeep, if they are 2 separate units why do you need to mess with the evaporator? Is it an access problem?

just curious!!

psycho

Reply to
psycho_pastrami

At least the weather is still mild in much of the USA. You can shunt the cooler lines together and drive the vehicle. Work on the core removal piecemeal if necessary. I don't advise it, but I often think of the possibility of using a nibbler to "unzip" the case and pull the core withour removing the box with the screws. Then duct tape or otherwise attach the case when done. OK, go ahead and laugh. Red Green never laughs at my ideas.

Reply to
WasteNotWantNot

Pontiac Fiero. Heater core under passenger side dash. Takes less than

10 minutes to gain full access, another 3-5 minutes to remove it, another 10-15 minute to reinstall. I changed my last one out in the parking lot at work, during my lunch break. :)

JazzMan

Reply to
JazzMan

Unfortunately, not always possible. On my old Plymouth, it had the same problem - AC needed to be disconnected to remove the heater core. We tried anyway. 1/2 the dash apart and started cutting the ductwork apart. Not gonna happen - the evap was basically what holds the heater core in. Not an A/C tech - ended up wussing out and taking it to a shop to swap.

Reply to
Ray

You are one lucky guy! I haven't had a car on which I could replace the heater core easily since the 1960's. Might try to find a Fiero next time I need a vehicle. But I'm sure there are many things that are very difficult to replace on the Fiero. The small engine compartment must make repairs in that area a nightmare.

Reply to
Loose Cannon

I tried it in my wife's 95 Explorer. I wouldn't recommend it. The case ended up in about 30 pieces. Just to add to the weekend long project, I had to track down and pay $95 for a "heater plenum chamber." I thought it might have saved me the trouble of stripping the dash all the way to the firewall. I was sadly mistaken.

Reply to
Jason

The core on my 93 Ranger started leaking a while back. After all the horror stories I'd heard about replacing them I wasn't looking forward to it at all. However, following the instructions in my Haynes manual, it took about

15 mins to get it out and another 15 to get the new one back in. It cost $20 at Autozone for the part. One of the easiest repairs I've done on the truck...
Reply to
Z.Z.

LOL!

The "small" engine compartment is quite easy to work in, and is large enough to install a small block Chevy in (a common swap). In fact, it's just as easy to work on an engine in a Fiero as it is any of the front-drive cars that it was derived from, like the Chevy Citation/Citation II, Pontiac Phoenix, Olds Omega, and Buick Skylark. And for major repairs, an experienced mechanic with a twin post hoist can have the entire drivetrain module out in under two hours, and I've done it with just two floor jacks in 3 hours.

JazzMan

Reply to
JazzMan

Agreed, My friend had the timing gear in her fiero strip and she came to me for repair. With the help and insight of Jazzman, the engine dropped out easily (other than the years of oil leaks and caked on dirt/mud/what not) and within two days, I had the fiero back, better than ever. Not a problem like the cadillac transverse Northstar V8. Try doing a couple tune up's on them.. Yeah.. REAL fun...

-Bruce

Reply to
Bruce Chang

"Bruce Chang" wrote

Oh come on, the Northstar is not hard to tune-up (replace plugs). And it's about as easy to get the Northstar drivetrain out as it was to get the Fiero drivetrain out. Though I never did remove the entire subframe and engine just to do a timing gear set. There are simpler and quicker ways to do that job. I miss that job.

Ian

Reply to
shiden_kai

I never said I removed the subframe, I said the engine dropped out.. the engine cradle is hinged and you remove two bolts and the cradle pivots out. Voila, instant access to the timing gear set.

-Bruce

Reply to
Bruce Chang

"Bruce Chang" wrote

Much better..... I guess I should have known that Jazz would have pointed you in that direction.

Ian

Reply to
shiden_kai

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