s14unimog

If its not one thing its something else... Yesterday I started smelling coolant through the vents and that quickly turned into, " I can't see a ****ing thing out the window!" Apparently coolant has found its way into the vents and I can't run the air/heat without fogging out my windows.

My question to those who have dealt with the heater core; is that the only place it can leak from? 1997 Model XJ

I checked out this thread http://www.jeepforum.com/forum/f11/m...thread-592844/

and from what I can see on his, it looks as though I can only remove/replace my heater core.

When I was looking around on the truck this morning I noticed that I have a noticeable drip coming from the heat/cold blend mechanism; its the one you can see just under, and to the left, of your glove box. and the "frame" rail on the passenger side is noticeably wet.

Is there ANYTHING I can try before removing/replacing the heater core?

jeepride

You can bypass your heater core by hooking both heater hose together or just block off the heater core inlet hose.

sems

The heater core is the only thing inside the passenger cabin that can leak coolant. Unless you do not want any heat there is no way of taking care of it without replacing the heater core.

s14unimog

Figured this much... damn it. Well luckily I reside in GA and the weather is getting warmer so I went a head and "looped" the heater line with one of the heater hoses.

I've got to rebuild my AX15 and just don't have the time/energy for this too.

Another quick question, if someone knows, is the 4.0 pretty good about working the air out of the coolant system. I'm guessing that's what's happening but since "looping" the heater lines, it keeps over heating... Surely this is just a air issue; yeah?

tjwalker

On a 97, air normally works it way out of the system on its own in about 3-4 COMPLETE heat up / cool down cycles. Keep tabs on the coolant level in the reservoir as it usually sucks some in as it burps itself.

If after 4 heat up cycles, this is still acting up, you have something else going on.......

s14unimog

noted and thanks for the response but it seemed to be doing well prior to the heater core bypass. I got some CLR and did a coolant flush. I'll work on purging the lines tomorrow; I'm sure it'll be fine.

Firestorm500

The dash and the A/C evaporator have to come out to replace the heater core.

I was looking at a 2000 model back in November that had a heater core leak and dead battery.

Had been sitting up for at least six months.

105K miles.

The owner was a young single mother with 2 kids.

I talked to my local mechanic who said the R&R on one of those cores would be about $650 plus parts.

I saw $850 and up online.

I passed on the Jeep. I figured that lack of money for maintenance, plus it had gotten hot several times, had probably taken its toll.

Those models are prone to head cracking.

s14unimog

^ I think any head is prone to cracking if treated poorly enough. I will never take my truck to a mechanic, I do anything and everything on all my vehicles. I flushed and refilled the coolant system this morning and all is well; even had time to get the new muffler on. I'm going to run a bypass on the core until it gets cold again.

I started this thread with hopes of finding out about some potentially common heat/cold blender valve issue that could be accessed/replaced without pulling the dash; doesn't seem like that's gonna happen. Does anyone have any information regarding the heat/cold blender valve assembly by its self? Could it be leaking from there?

Firestorm500

No, the 2000-01 heads seem to be much more trouble prone than your average head.

If you want heat, you're gonna have to bite the big one and pull that dash.

Sorry.

s14unimog

no worries, it'll get done. Luckily I live in GA and its spring time. Know much about that blender valve assembly though? There has got to be a valve to inspect.

Firestorm500

It's in the engine compartment, just forward of the firewall on the passenger side.

Notice it is on the engine side.

Incidentally, it's going to be 39 degrees Monday night here in Arkansas.

Heck, it was 39-45 degrees for daytime highs some of last week.

s14unimog

Yeah, not the case here. Sunday was quite nice and this morning it was in the mid 50's. I guess that valve is in fact out of the question...bummer.

Thanks for the help.

No4x4Yet

My buddy was tellin me how he cut the heater box to remove the heater core and replace it. then used some black RTV to seal it up. Worked great and save from pullin everything apart. I wasnt on a jeep but should still work right?

s14unimog

eh.... I'm not shy about pulling the dash so I'd rather not cut it up. I did find a write up about removing the dash and it didn't look like that's any easier than actually removing everything.

I'll worry about it come winter time.

No4x4Yet

Yeah I looked over a thread on it too. Dont think itll work too well with those long pipes.