Grrrrr. Anti Freeze leaking into my interior

[rockable]

I was driving home today and sniff, sniff, I smelled anti freeze.  Looked down and it was running into my PS floorboard.  I quickly made sure the heat lever was moved to full left and it seemed to shut it off.  I'm guessing that my heater core is bad.  Is there anything else in the heater box that could leak or is my initial suspicion correct?

Grrrr.  25 year old pickup truck.   Grrrr.

[80stepsideguy]

Yeo,

either heater core is gone or you got a hole in the hose.More then likely the core is shot.

thanks
Pat

[rockable]

That's what I thought.  I replaced the hoses about 6 mos. ago.   

[big bear]

man....thats no way to enjoy a friday haha  sorry to hear  hope its an easy fix

[zieg85]

Mine is leaking as well, going to put a bypass in and fix it in the fall.

[rockable]

Got my new core and will attempt to do the install this morning.  Wish me luck.  I'll post anything that I think you'll find interesting.

[rockable]

Nothing out of the ordinary. My truck has AC.  Took me 3-4 hours to complete the job.  The biggest challenge was the one nut directly under the heater core in the engine compartment.  That one was a little tough to get off and to get the nut started on again.  Other than that, no problems. 

I read some post where some guy was going to cut his firewall.  Do NOT do that.  It is not that hard to do this.  The biggest pain in the butt is that most of the fasteners are metric but some are inch.  You have to have two rails of sockets to work on it.

[beastie_3]

drop the inner wheel well, much easier.

[Low87]

I tried this over the weekend.  Once I got the PS side of the suitcase off (dropped the inner fender like beastie said), all I could see of the heater core was the two tubes sticking through two slightly larger holes in the firewall.  It had already been a long day so I buttoned everything back up and saved it for another time.  Any ideas?  Need to tackle this soon.
Also, after opening up the firewall suitcase, it obviously messes up that black goo that's in the seams.  I didn't have anything to reseal it with, and now clear water drips from that box.  Is having it unsealed messing with the evaporator in there? 

[VileZambonie]

It's pretty easy even if it has A/C. That black gooey stuff can be purchased at the auto parts store. Ask for Butyl Tape (or dum dum) Dropping the inner fender allows easy access to the hard to reach stud/nut.

[87454westernhauler]

I have replaced about 3 heater cores on these trucks now, alll with AC and know haow much fun they are!!

[thirsty]

We are lucky that the heater cores are pretty easy to change in our trucks. Some vehicles are such a pain that it makes ours seem fun.  Still nobody wants to do one in any truck or car.

[Low87]

I must be looking at it wrong then.  I'll give it another go.

[ehjorten]

There is no need to mess with the AC on the engine side of the truck when replacing a heater core.  Best advice from others here and from doing it myself is to drop the fender liner to access the hard to reach nuts on the bottom.  The factory service manual does not say anything about doing this step, but I don't really see how you could realistically do it without removing the fender liner.

The heater core is in the box that is inside the cab.  It is held on with 4 studs and one bolt IIRC.  The case that holds the AC Evaporator core and the blower motor does not need to be removed or basically touched to do this.

When you are in there, check the vacuum door servo to make sure that it is working properly, that the blend door is functioning as it should and think about replacing the foam seals on the defrost door and around the heater core.  I did it with simple adhesive backed foam tape (the kind you would get for sealing between a canopy and truck bed.  The staples in the defrost door are pretty easy to unbend, remove and replace.  Check the vacuum hoses too for cracks and brittle-ness.

[beastie_3]

Another reason I like dropping the inner fender is you can sit on the tire and work without leaning over. As for the heater core itself, you have to take the box off inside the cab as well. the two boxes kinda sandwich the firewall.

The butyl tape is usually found in the weatherstripping section of the parts store. Ive walked past it many times while actually looking for it.