Engine/Transmission (1994 - 1998) heater core?

[MBSmith]

cant take it anymore. . Will the windows fog up and actually leave a foggy haze on window. And smell sort of like anti freeze. need to buy tomorrow it is getting nasty. I think i also read somewhere about replacing something else while doing the heater core. Evap... or something like that. Thanks guys I think it is actually starting to make me feel sick.....

 

[fest3er]

... Thanks guys I think it is actually starting to make me feel sick.....

Which? The antifreeze? Or the anticipated 'joy' of spending 6 hours dismantling and remantling your dashboard to fix it? Hope you have a heated shop to work in. I don't, so mine'll have to wait until spring. And until I fix the trans leak.

 

[MBSmith]

I don't want to fix it. it is just getting to be a bit unbearable. it is to cold to keep windows down. oh well.

 

[mhelburg]

You can always pull the heater hoses going to the firewall and couple them together. You won't have any heat but it won't leak.

 

[GAmes]

If your A/C is working, don't fool with the evap. Here is how to replace the core without removing the A/C lines. https://www.turbodieselregister.com/magazines/Issue_046.phtml



Look on page 12

 

[KKohagen]

If your A/C is working, don't fool with the evap. Here is how to replace the core without removing the A/C lines. https://www.turbodieselregister.com/magazines/Issue_046.phtml

Look on page 12

I just replaced the dash top and the heater core. Now that I have done it the hardest thing was getting the replacement heater hoses and removing the one bolt on the firewall back behind the valve cover. First time I was given the wrong hoses. I used a 1/4" drive deep socket 10mm to take off the bolt.

The procedure worked, I forgot to move the air bag module until after I had already moved the dash down. It made for contortionist practices to get at it.

The bolts on the side of the dash for my 2002 were 1/2" bolts, dash bolts and the ones inside of the engine compartment were 10 mm and 11mm.

It is actually not as hard as it seems. Take your time. I put each section of screws/bolts into small zip lock bags and labeled them with a sharpie.

Hope this helps.

 

[Matt42]

Ground The Heater Core!

The heater core ground wire on mine was loose from the factory. I suspect that the resulting electrolysis is what led to the pinholes. When I replaced the heater core, I used one that had the flexible input and output tubes set in nylon seats. I made double certain sure to affirmatively ground all of the metal parts of the new heater core to the chassis.



It was not fun, but it was certainly educational. I suggest replacing the plastic sockets in the firewall just below the windshield. These receive the sheet metal screws that hold the dashboard in. If you don't replace them, expect rattles and squeaks from the lower windshield area. They will cost $5 to $10 each (gasp) at the dealer. I paid it and was glad I did. The heat here destroys plastic stuff.



For what it's worth, my then-teenage daughter and I had a memorable father-daughter bonding experience returning from Colorado a number of years ago during a cold snap and snow storm as we discussed which evil to select; being cold from open windows to keep the windshield clear or being sick from the nausea of antifreeze vapour. In the end, we chose being cold because it was less nauseating, the heater core vapour fogged up the windshield anyway, and her Game Boy still worked at 18F. :-laf



It was then I decided to do the work.

 

[rrl989]

Prestone makes a good "Stop Leak" that could stop the leak. Could be temporary or permanent.

 

[Matt42]

Prestone makes a good "Stop Leak" that could stop the leak. Could be temporary or permanent.

I tried that. For some reason, it didn't help the heater core in my truck.

 

[mhelburg]

Aluma-seal is, IMO, the best "snake-oil" I've ever used. I've sealed up all different types of coolant leaks and will not leave home without it, in case of emergency.

 

[Matt42]

Aluma-seal is, IMO, the best "snake-oil" I've ever used. I've sealed up all different types of coolant leaks and will not leave home without it, in case of emergency.

I will not argue, and I will agree. I carry a tube in my boonie box also. For big cooling systems, carry two tubes, or find a place that sells the big tube. But a word of warning based on bad experience on rough roads in a hot, dry climate. Wrap the tube in duct tape, or keep it inside a thermally sealed heavy polyethylene bag. Over time, the clear plastic tube starts to deteriorate and will eventually crack open. The aluminum will leak out and get into everything in your tool box, glove compartment, carpet, or wherever.

It's funny now, but it was really annoying then. The mess was spectacular, since those tiny bits of aluminum go everywhere! :{

 

[surfbeetle]

Question on the dash removal and ac evap/heater core replacement... If the windshield were out, would it make the job any easier? I have to replace the windshield at some point and was wondering if it would be best to just do this all at once.

 

[The patriot]

I did mine last winter, in a snowstorm.

T'wasnt fun.

In the last year and a half I had my dashboard out probibally 6 times. I have no clue why it isnt cracked yet.

 

[Matt42]

Question on the dash removal and ac evap/heater core replacement... If the windshield were out, would it make the job any easier? I have to replace the windshield at some point and was wondering if it would be best to just do this all at once.

I don't think it would matter much. Might be a teensy bit easier to get the top dashboard screws out, and easier to pass tools around the hood into the cab. It was handy to have the windshield in for me, since it rained during the job.

 

[KKohagen]

Windshield in or out would not have made much of a difference to me during my heater install.
I used a simple webbing cinch strap attached to the rear seat anchor strap/hook and the dash to hold it up out of the way.
I have some pictures if needed.

 

[FireChick]

My core just blew up today I think. I've been having AC/heating problems for about 2 yrs with the last year of smelling coolant and a very fine vapor occasionally and limited heat.



Today, turned the defroster on and suddenly thick white smoke came out of every vent. Smells like a structure fire happened in my truck (that takes me back to the days of fighting fire - yummy - but NOT in my truck!!!) #@$%!. The bottom of the box that the heating core sits in was warm.



This is not good for me when it's freakin negative COLD outside in New Hampshire. I think I have to change the AC evaporator at the same time. I've done many things on my truck myself but I've never done this and have heard it takes a bit to do both the core and the evaporator. One, problem... . I have to do this in the elements and as I've said - IT'S NEGATIVE COLD OUTSIDE! I also don't have the money to have someone do it for me, unfortunately. If it was warm outside, I would have no problem trying to do this myself.



That being said, would anyone be willing to share their heated garage (and maybe some man power) for, oh about 8 hours?



There would be beer distributed freely Oo.



Oh, I'm in Francestown, NH

 

[CBlack]

GAmes posted the procedures I used, written by Joe Donnelly. The only thing I didn't do is remove the airbag module.



The biggest pain the arse was putting the A/C box back in by aligning those 4 bolts. Luckily, my bride was there to help me.



I also glued my dashboard back together and put it back in and now I need some matching paint to help it out a bit.

 

[Skydiver]

When y'all get finished helping FireChick come on down here and replace my heater core. Also bring any beer that's left over so I won't have to buy it. I will cook a great meal. Hey it's been above 70F for 3 weeks now.
That would be a nice give away item for the TDR contest. Something we can use. Might as well break up the give aways into sections. (first, second, third generation) it really is allready broke up tnto sections now.