awork

I have a 97 Jeep cherokee 4.0. I believe my heater core was going out but not sure. I talked to a couple mechanics who believe there could be another issue. I have recently changed the thermostat and water pump. When first turning the heat on it has a sweet smell like antifreeze. after a minute or two it goes away. The heat never gets very warm though. I checked the passengers floor board and it is damp but does not smell like antifreeze. I have checked the coolant level to insure it is good for cold temps.
Any ideas on if the issue is the heater core or something else? I dont want to spend the money fixing it if that is not the issue.

Larry's XJ

Try back flushing the core first. Look for any hose leaks , especially near fire wall.

What does temps have to do with coolant level

awork

I dont think i would be able to flush it right now. It is currently about 5 degrees here. If we get a warm day i may try though.

wakymilo

I am not a mechanic nor am I mechanically inclined, I did however have the same issue. I did everything you did and it never got better eventually my windows started to get this weird filmy mist thing on them idk how to explain it so I took it to midas and they told me my heater core was leaking but they wanted like 1200 bucks to fix it so I left. I bought the book and called a friend and we had to remove the whole inside dash and my friend was in and out so I was kind of alone taking this on. It took me 9 hours but I finally replaced the heater core then I did a full flush and its been great ever since. I have a 99 cherokee classic. Good luck!

Larry's XJ

Funny, that's what the temp is here in Lapeer, mi right now, -15wchill. Not "warming up" till next week.
How's that global warming going for you?

Funny thing about the antifreeze on windshield. I once grabbed the wrong jug and put antifreeze in washer bottle, what a mess that was

awork

Wakymilo- Thanks for the info! I am about 95% sure that is what mine is going to end up being, just wanted to see if there are any other possibilities. I plan on looking this weekend and see if I can find the leak just to confirm its not a hose leaking.
What heater core did you end up getting? Also what book did you get to perform this surgery? Mine is a 97 but did you have to uncharge the ac before you did it?

wakymilo

I got the chilton manual it's all they had at the store. You do need to un charge the AC however mine has the ac removed so I didn't need to do that. I can't remember which heater core I got, it was just the cheapest one they had at auto zone I believe it was like $75.

Nottingham15

I had the same issue which I fixed a few days ago.
I had a blocked heater core and clean water dripping from behind the glovebox.
The water was just condensation that had collected due to my turning off the fan as it was just chucking out cold air. When I turned the fan back on the water just dropped through the newly opened air door.

To unblock the heater core I disconnected the hoses at the front of the engine. Water from the garden hose wouldn't unblock it so I connected my cigarette lighter tyre inflator to the return hose, sealed it with a bit of foam and the spring clip then pushed air through it. It took about 2 seconds to clear the blockage and blow a load of filth out.
I then flushed and back-flushed with the garden hose until the water was clear, blew that water out with the air, reconnected the hoses and topped up the coolant.
I now have hot air.

I was expecting to have to take it to a garage for a new core at great expense.
It was actually about the easiest DIY job I've done on the Jeep other than changing the oil. It seriously took me less than 30 minutes.

Give it a go. It might save you a load of cash.

awork

Nottingham15- Man you got lucky on that one. I hope that I have the same luck, I may try it this weekend. Did you have a slight antifreeze smell when you first turned the heat on?

Nottingham15

Nothing that I noticed.
Seriously, as long as you don't think your core has a leak, give it a go. I was on the verge of booking it in and expecting the expense of a new heater core but thought I'd try it myself after watching a youtube vid (something like "redneck heater core fix").
It was ridiculously easy once I'd figured I could use the tyre inflator with an adaptor as a source of compressed air.

xjgreen

If it is the heater core go ahead and replace the evaporator core while in there. I would also put in a new ac dryer as well.

freegdr

Deff ^^^^ once your in there if its being done do it all the way.