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Old Dec 25, 2021 | 10:48 PM
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Heater Core Replacement

Howdy y’all. First time poster here but longtime 1999 F250 CCSB 7.3 owner. I’m a pretty average shade tree mechanic with access to a full lift and garage on a local military base but also enjoy thoroughly researching my next fix before I attempt it.

The problem: I recently traced a coolant leak under the front passenger door to the heater core. Every YouTube video I’ve watched makes it seem like an incredibly easy .5-1 hour job… Speaking in hypotheticals, if I were to disconnect the battery (is this necessary?) and drop the heater core without draining some coolant would my biggest problem just be spilling coolant in the cab or am I turning a blind eye to something else here? Also, after I attach the new heater core and put everything back in place, do I need to somehow bleed the lines or will the water pump/degas bottle do that all for me? Of course I’ll add coolant to the degas bottle if it’s below the full line after letting it run a few minutes.

I really appreciate any and all the input here. I was sent over from Reddit where I didn’t get too many responses. Thanks!
 
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Old Dec 26, 2021 | 05:03 AM
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It is an easy task if you have done it before. If the system has not been touched in awhile and the quick-connects for the heater hoses at the firewall are caked with crud or brittle with age, you may be in for a challenge. Access to the heater core is reasonably good after removing the glove compartment. Plan to replace those quick-connects no matter what. I would drain enough coolant to drop it below thermostat level. That should keep too much from flooding the passenger floor's carpet. I do not really see a need to disconnect the batteries if you are not disconnecting anything electrical but it doesn't hurt to play safe. There is no need to bleed as coolant will flow through it as a matter of course. I have attached the heater core removal and installation procedure from the shop manual.

Replacement heater hose quick-connects:
https://www.oreillyauto.com/detail/c...AT+28500&pos=0

While you are in there, you might want to consider a heater hose cutoff valve so you get colder AC in the summer.
 
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Old Dec 26, 2021 | 05:35 AM
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Chilibball,
You need to remove the instrument panel (dash) to get the plenum (hvac case) out and replace the heater core
Absolutely ignorant bitchy about 9-15 hundred dollar job
You can do this yourself if you have some serious gumption
Alldata at the library has the procedure printable for free (Ford service literature)
Ton or screws to get the dash out and the one above the column gets most people
Follow the procedure and sit the dash on the seat
Its easy from there
 
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Old Dec 26, 2021 | 05:39 AM
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Replace both heater hoses with the new quick connect couplers on them
You should be able to get a heater core and both hoses for 150 online
Aftermarket parts are okay for this job and I usually pressure test the new core before I put it in
 
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Old Dec 26, 2021 | 06:56 AM
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@chilibball , welcome to the FTE!

If you desire a free copy of the Ford Service Manual very similar to what you would see on AllData, see the link below.

Link: https://www.ford-trucks.com/forums/1...hlight=Service

On the other hand and in addition to the advice offered above, we can provide the written and illustrated instructions from Ford for removing the heater core if you only prefer to have that portion.
 
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Old Dec 26, 2021 | 11:10 AM
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Originally Posted by FordTruckNoob
It is an easy task if you have done it before. If the system has not ben touched in awhile and the quick-connects for the heater hoses at the firewall are caked with crud or brittle with age, you may be in for a challenge. Access to the heater core is reasonably good after removing the glove compartment. Plan to replace those quick-connects no matter what. I would drain enough coolant to drop it below thermostat level. That should keep too much from flooding the passenger floor's carpet. I do not really see a need to disconnect the batteries if you are not disconnecting anything electrical but it doesn't hurt to play safe. There is no need to bleed as coolant will flow through it as a matter of course. I have attached the heater core removal and installation procedure from the shop manual.

Replacement heater hose quick-connects:
https://www.oreillyauto.com/detail/c...AT+28500&pos=0

While you are in there, you might want to consider a heater hose cutoff valve so you get colder AC in the summer.
Thanks for the writeup! It does seem like a relatively simple job. The O’Reilly’s link you sent me is interesting. I ran across the exact same part and stopped by a Ford dealership last week and they claimed it wasn’t applicable to my truck but I can clearly see them connected to the hoses. I’ll have to buy a pair tomorrow.

I was about to start the job today until I realized I left my socket wrench kit at my brothers and now football is on. I’ll have to tackle it tomorrow after work. Thanks for the info!
 
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Old Dec 26, 2021 | 11:11 AM
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Originally Posted by manicmechanic007
Chilibball,
You need to remove the instrument panel (dash) to get the plenum (hvac case) out and replace the heater core
Absolutely ignorant bitchy about 9-15 hundred dollar job
You can do this yourself if you have some serious gumption
Alldata at the library has the procedure printable for free (Ford service literature)
Ton or screws to get the dash out and the one above the column gets most people
Follow the procedure and sit the dash on the seat
Its easy from there
If I recall correctly a full dash removal is only required for F150s. I was able to find the heater core cover earlier today behind the glove box fortunately.
 
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Old Dec 26, 2021 | 11:12 AM
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You are very welcome.
 
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Old Dec 26, 2021 | 11:13 AM
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Originally Posted by manicmechanic007
Replace both heater hoses with the new quick connect couplers on them
You should be able to get a heater core and both hoses for 150 online
Aftermarket parts are okay for this job and I usually pressure test the new core before I put it in
It’s funny you mention the quick disconnect adaptors. I was at a Ford dealer last week buying a set of them and the parts rep claimed my truck doesn’t use them… I looked under the hood and I saw them clear as day though. I’ll have to stop by tomorrow and buy then regardless.

edit: typo.
 
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Old Dec 26, 2021 | 11:14 AM
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Originally Posted by Sous
@chilibball , welcome to the FTE!

If you desire a free copy of the Ford Service Manual very similar to what you would see on AllData, see the link below.

Link: https://www.ford-trucks.com/forums/1...hlight=Service

On the other hand and in addition to the advice offered above, we can provide the written and illustrated instructions from Ford for removing the heater core if you only prefer to have that portion.
I appreciate the link! I was going to tackle it today until I realized I left my tools at work so I’ll have to give it another go tomorrow. At least it gives me more time to check out that service manual. Thanks again!
 
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Old Dec 26, 2021 | 06:27 PM
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That'd the beauty of these old trucks you can remove it easy and can do it in a jiffy, just the other day had to change out a heater core on our 2016 ram 6.7. The entire dash had to come out as well as the hvac system, surprisingly it's not hard after watching a poop tube video and knowing where the bolts are to remove it.



 
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