After consulting the unTrusty Haynes .... I have more questions than before.

I have a 90 XLT with Air Conditioning. Is the heater core removed from inside the cab behind the glovebox or under the hood .... and if under the hood, do I have to disconnect A/C?

 

Its not to bad, just remove the glove box and there is a cover with 15 screw/bolts, i think. Then remove the 2 hoses from the firewall and wiggle the thing out. Took about 30 mins the first time i did it. Hope this helps.

 

yup not a biggie at all


did mine in about the same

Y do you think it needs removing ?

 

drain a little coolant from radiator first, note which heater hose goes where, it is a 10 minute job.

check blend door for obstructions when core is out.

 

Thanks .... was just not sure if my truck had the one you access from inside the cab. Will check it all out. Did the one on my Mach 1 many years ago ... total PIA since the whole A/C had to come out.

 

I did this last Saturday on my 90 f150.
Remove the glove box.
Unplug the vacumn line connection and cut it loose if still taped to the heater core cover.
Pull the blend door cable out of the clip in the uppper left corner and push it behind the cover and leave it connected.
Remove about 6 screws.
Pull the loose cover towards you and work it out thru the glove box opening.
Drain a little bit of coolant from radiator.
Remove both heater hoses, and duct tape them to something so they don't fall down and drain the entire system.
Push on the two heater tubes from the engine side.
From the inside, pull the core out and work it out carefuly towards the floor. Careful is so you don't spill the coolant in it.
Remove the pen, pencil, kids toy, or in my case the deck screw stuck in the blend door opening.
Take the core to the parts house and discover the one they have is not exactly the same size. Drive to everyplace in town and find that everyone has the same core.
Give up and go back to your favorite parts place and find they just sold the only one, the same one you looked at 3 hrs ago. Go to the zone and get it for $20.
Reverse steps to install. Use a piece of rubber weatherstrip to fill the gap so it doesn't bounce around when you drive. Reconnect the blend door cable and adjust if necessary, by listening for the door to clunk as you move the temp control lever.
Refill the radiator and park it on an incline with the cap loose and idle it for 30 minutes.
Top off the radiator and over flow tank.
Shut the hood and hand your son the keys, and hope he brings it back intact, in a few days.

*** some steps are optional

Good luck Frank

 

Thanks ... Seems most here don't like the AZ Cores .... I will try some others, and I know about driving all over town .... at least more of the parts stores are open here, but with all the extra pickups in town, they don't always have common things. With all the Roofing peices and nails on the roads .... the First thing to be in very very short supply in this area were 16" Truck Tires .... at least I have 15's.

I noticed a small leak on the ground above the heater core area this weekend .... wasn't using A/C so thought it must be the Heater Core. If it leaked it would either be from the A/C drain or the hoses .... right?

 

Defrost setting kicks the compressor on too. Just a thought.

 

Probably from the a/c running in defrost, but if you have antifreeze in the system, you can tell if it is coolant by touching it. It will be slick feeling even if it doesn't have a noticeable color.
Usually if the heater core leaks, it drips into the floor of the cab, and you get that distinct smell of hot coolant, along with fogging the windshield.

 

No ... defrost was today ... not this weekend. It was coolant .... I am not sure where it came from, but I do not smell AntiFreeze inside the vehicle like other core failures I have had in other vehicles, but I would think if it leaked ... it would come out through the same place as the A/C condensation goes, has for older ford cars and vw cars for me. This weekend I will investigate further, if I don't find anything outside I will at least pull the core cover off to see if it is wet in there.

 

I was in my heater last weekend. The heater core is lower and downstream from the a/c. If the core itself, not the inlet/outlet tube is leaking, it pretty much has to build up in the box, and drip into the cab.

 

Okay .... then I guess that means it must be from someplace else .... will have to check the hoses, I replaced them a few months ago when I did the Rad ... maybe they are not tight enough.

 

SS,

just replaced mine (heater core) this weekend ('93) and it leaked from one of the two hoses going into the core dripped along frame just under pax side of firewall. Very insidious though and I couldn't actually see the leak and which hose was the culprit. just the coolant pool underneath. replaced the factory clamps with old school screw clamps and it fixed the leak.

good luck
tater