My heater core was very rusty when i did this. It was plugged-i’m talking no heat at all. I reversed flushed it as you did(8 gallons), and that unplugged it a little (awesome), But the flow was still limited. Heat was now luke-warm. After a second flush, the heater became much warmer. Incredible amounts of rusty water came out. Theres still some in there definitely, so upcoming this weekend will be my third heater core back flush. I’ll probably use some sort of cleaner to help me out with this one final time. Best regards
My old family mechanic was very old school. He told me how to use work toilet cleaner in it. It worked great on my truck. Just know to dilute it and protect your painted surfaces.
No chance I could get my hoses off after 19 years so they had to be sacrificed. Finding a molded upper hose has been impossible. I ended up just using a straight (5/8?) hose from Autozone for a few bucks and been running it the past 5 years. If you ever find a molded upper hose please let us know!
That’s a good tip. Next time I do this I’ll have to look for something like that. I had a hard time getting a good seal as well, as witnessed by the water flying everywhere. :) Thanks for watching (and sub’ing?).
I won’t lie - I was expecting something like half a pound of rust to come pouring out so I was a bit disappointed. It’s hard to say in the middle of summer but I do think it blows hotter now so who knows.
@@jettexpress123 Thanks for watching, Jett! I don’t own the TJ anymore but I made something like 70 videos with it. My email is in my “about” on the channel if I can help some way. Also check out @ForceBuilt. He’s got a ‘97 TJ as well with lots of good videos on it.
To be honest, I’m nervous about doing anything to TDSR that involves touching systems that are working. Good idea to flush it all? Perhaps. But since the coolant system is currently working, I didn’t want to risk it.
When I look at the 2000 TJ Service Manual (page 7-2), it shows supply to the heater core is the bottom and return to the engine is the top of the heater core (just like my '97 TJ). Or at least, that's what the illustration shows that it should be. Is it possible your hoses got reversed at some point? Link to service manual: wranglertjforum.com/attachments/2000-tj-service-manual-pdf.362948/ Thanks for watching, James.
@@CarbonsDIYGarage fabu video Carbons. Thank you for the help. Not many 2.5l 4Cyl jeep vids out there. However, you are right. Looking at the manual (btw thank you!) diagram, the hose from the t-stat is going to the top. It's 11/16 from the t-stat and 5/8 from the pump. Let me check my jeep to double check. Thx so much!
Not stupid! Jump to 9:36 in the video. You can see the green coolant going into the smaller/lower hose. Off camera, I'm pouring coolant (via funnel) into the hose (and holding the hose up) to push/get coolant into the heater core. You can see that coolant then comes out of the top hose, meaning the core is full. But to answer your question - funnel into the hose off camera. (and I forgot how loud/annoying the lawn services were that day) Sorry the video wasn't clear on that; thanks for watching.
This guy went about flushing the heater core all wrong, the best thing to do is to leave the hoses attached to the heater core and disconnect them from the thermostat and block pull them up over the air intake, buy a standard garden hose adapter female end and connect hose from your house and flush for 45 seconds, then disconnect the garden hose attachment and place it in the return end and flush that way for 45 seconds after blowing out with compressed air or your mouth, the inset a funnel into the return side(larger hose) and pour enough white vinegar till it pours out the other end and let sit for 10 minutes, after repeat flush with water, then reattach hoses as normal and run engine to operating temperature should increase heat and engine will run slightly cooler, I gained almost 40 degrees in heat
Thanks for the comments! I dunno that there's that much difference from what you describe and what I did. I clearly didn't leave the hoses attached to the heater core, though I could have, like you suggested. Instead I just used my own, clear hoses. I'm not sure it makes a difference except I didn't clean out the small lengths of hose between the core and the t-stat and block. A hose adapter is definitely a good add and I'll be doing that if there's a next time. The hose sprayer did not work well. The vinegar idea isn't something I've seen before. It sounds worth investigating since it works well for mineral deposits on home plumbing fixtures. Is it certain the acidic vinegar won't cause problems with the materials in the heater core? I'm happy to report that with us being in cold December now, my TJ's heater temp output is way better than it was before I did the flush 11 months ago. Thanks again for the video review.
@@CarbonsDIYGarage that additional water pressure could damage the heater core , so you're not off there. You need to pump distilled water in there and not tap water. The vinegar idea could breakup some rust in there, but if that's what you're doing , you need that core taken out and replacing it.
@@CarbonsDIYGarage I think most cooling system/radiator flush kits are basically vinegar or of the like. The water pressure is also an issue with hoses. You don't want to have to take out a dash to replace a heater core. It's miserable. I think the core is rated for around 13psi and garden hoses are probably around 40.
Yeah, I got the flow direction from the factory service manual. But I just went and looked at the hoses. Both actually say “heater” on them and the hose size. But no flow direction info. It would be great if they put flow arrows on them. Thanks for watching.
Dang. Im impressed by all your projects. I am learning a lot from you. Question...How do you come up with these projects? Do you just go after items that you are having problems with? OR is there some master list of maintenance items that should be done?
Well, it's kind of both. Mostly it's just tackling projects as they come up. When I first got the Jeep it needed a LOT of work so I just made a long list, put them in priority order, and just worked them one at a time. Of course more things broke over time, so those got added to the list as well. There's also schedule maintenance like engine/diff/transfer oil case changes, filters, brakes, spark plugs, etc. Then there's just improvements I want to make, like the door jamb switches on the TJ or the suspension list on the JKU. Of course every time I seek a video on how to do something I come across others that "man, I should do that too" so it goes on the list.
The Jeep's my son's daily driver and he says the heat has been great all (south Texas) winter so far, so it looks like the flush did the trick. Thanks for watching.
@Carbon's DIY Garage Yw. Thanks for the quick reply. Looks like I need to do this. Lol. Thank you for the links for the clamps and hoses. Will def make it easier. 😎👍
@@---rg1gb The passageways on these little cores/heat exchangers are small and easily blocked up. It wouldn't take a whole lot to start slowing the flow. At least that's my theory. It would be interesting if people commented on how much "junk" they get out of their core compared to how little heating they're getting.
Thanks for watching, art! So far the coolant system is working well and the coolant still looks green. A flush is on the list of things to do but probably not in the near future since TDSR has a few items that need to happen sooner than later. I guess we'll all have to stay tuned and subscribed to see when the great flush happens. :)
By the way, if I had to do it again - and especially if I was flushing the whole system - I wouldn't use the hose sprayer. I'd get a nipple adapter for the hose so I could better regulate the amount and pressure of water going into the system. The sprayer worked fine for the little heater core but I don't think it'll work well for that bigger volume/job.
Thanks for the video! Well...has it gotten cool enough for you yet to try out the heater? My son just got an 01 TJ, 2.5l for his first vehicle. Tried his heater last week and it was not hot at all. He has several other unrelated issues so this isn't a huge priority now, but still curious if this solved your problem. Enquiring minds want to know.
Thanks for the reminder! The Jeep's my son's daily driver and he says the heat has been great all winter so far, so it looks like the flush did the trick. Thanks for watching and good luck with your 2.5L TJ! (Our TJ is also my son's first vehicle)
Shawn Hudson I have a 2002 TJ 4.0 that also has a heater issue. It puts out warm air but not hot. The door mechanism runs when going from hot to cold and I flushed the heater core with no obvious debris coming out and no noticeable change in temperature. I am leaning towards the temperature control switch being faulty but am not certain. If you have found the problem on his Jeep I would appreciate knowing what it was. Thanks and good luck!
Thanks for watching (and subscribing?), Jason! If you're talking about the doors on TDSR (e.g. 10:12), those are just the stock metal half doors. The upper doors are solid sliding glass windows vs. the more typical roll up plastic windows.
I *think* the answer to your question is "yes." It felt a lot hotter when I tried it out, but it's also summer in south Texas so I'm not really sure. Real test probably won't come for another 3 months or so.
@@CarbonsDIYGarage temps should be at the floor duct (according to TJ service manual) 144* F on full heat, floor blower. my 2005 is at 100*, I need to do a heater core (already flushed core) replacement=big big job 😨
@@lorax1968 Ah, great! Thanks for that info - never thought to look for that in the service manual. I have looked in the service manual on replacing the heater core and/or removing the a/c box - big job indeed! I've got a/c as well, making it even more complicated. Good luck on yours (and thanks for watching)!
Thanks for watching, Scott (and subscribing?)! I have to LOL - TDRS is a typo. It should be TDSR (and I've now corrected it in the video description). TDSR is shorthand for the temporary name I've given to this Jeep (That Doesn't Sound Right). TDRS is an acronym I use often during my day job and clearly type it way too often so I didn't even notice my error.
@@CarbonsDIYGarage You actually got the acronym RIGHT in your comments section, I typed it wrong. Lol. Thanks for the clarification. And the video. I had no idea about the hose pliers.
Check out the video description for extra info, parts, tools, torques, and any updates.
My heater core was very rusty when i did this. It was plugged-i’m talking no heat at all. I reversed flushed it as you did(8 gallons), and that unplugged it a little (awesome), But the flow was still limited. Heat was now luke-warm. After a second flush, the heater became much warmer. Incredible amounts of rusty water came out. Theres still some in there definitely, so upcoming this weekend will be my third heater core back flush. I’ll probably use some sort of cleaner to help me out with this one final time.
Best regards
Great insights! It might take more than one fish to break it all loose. Thanks!
My old family mechanic was very old school. He told me how to use work toilet cleaner in it. It worked great on my truck. Just know to dilute it and protect your painted surfaces.
Great Vid, my heater has never worked better!! Thanks for posting. 👍
Glad it helped. Thanks for watching, Bobby.
No chance I could get my hoses off after 19 years so they had to be sacrificed. Finding a molded upper hose has been impossible. I ended up just using a straight (5/8?) hose from Autozone for a few bucks and been running it the past 5 years. If you ever find a molded upper hose please let us know!
This was helpful for me. Thanks for doing this
Thanks for watching. I'm glad it helped, Steve.
I did this on my 98. I bought a heater core flushing nozzle off Amazon and that really helped. I couldn’t get a good seal with my sprayer.
That’s a good tip. Next time I do this I’ll have to look for something like that. I had a hard time getting a good seal as well, as witnessed by the water flying everywhere. :)
Thanks for watching (and sub’ing?).
Do you have the link for that? I also have a 98
Thanks for this video. About to do it myself on mine having just replaced everything else in the coolant system.
Thanks for watching!
GREAT video, thank you very much.
Thanks for watching!
Just finished changing my heater core. I was surprised how easy it was compared to all the videos on the Internet 😅.
Good video Ed. It actually didn't look too bad. Mine was leaking so I didn't even attempt flushing of course. Keep it up!
I won’t lie - I was expecting something like half a pound of rust to come pouring out so I was a bit disappointed. It’s hard to say in the middle of summer but I do think it blows hotter now so who knows.
Perfect I found I have the same exact jeep. I need to connect with you sir somehow. I have lots of questions
@@jettexpress123 Thanks for watching, Jett! I don’t own the TJ anymore but I made something like 70 videos with it. My email is in my “about” on the channel if I can help some way. Also check out @ForceBuilt. He’s got a ‘97 TJ as well with lots of good videos on it.
It worked!! Thank you very much. 🙏
Like the clamps. I'll have to get a couple. Did you consider running radiator flush through the core?
To be honest, I’m nervous about doing anything to TDSR that involves touching systems that are working. Good idea to flush it all? Perhaps. But since the coolant system is currently working, I didn’t want to risk it.
@@CarbonsDIYGarage Radiator flush through the core just like you were doing, then flush with water and hook the hoses up again.
My 2000 Jeep 2.5l SE the top hose is the supply & bottom is return. Not sure why.
When I look at the 2000 TJ Service Manual (page 7-2), it shows supply to the heater core is the bottom and return to the engine is the top of the heater core (just like my '97 TJ). Or at least, that's what the illustration shows that it should be. Is it possible your hoses got reversed at some point?
Link to service manual: wranglertjforum.com/attachments/2000-tj-service-manual-pdf.362948/
Thanks for watching, James.
@@CarbonsDIYGarage fabu video Carbons. Thank you for the help. Not many 2.5l 4Cyl jeep vids out there. However, you are right. Looking at the manual (btw thank you!) diagram, the hose from the t-stat is going to the top. It's 11/16 from the t-stat and 5/8 from the pump. Let me check my jeep to double check. Thx so much!
@@jamesmonahan9408 Glad to try to help. Good luck with the 4-banger! :)
@@CarbonsDIYGarage oh considering the shape of her when I bought her anything is surely possible. Especially the heater hoses being mixed up.
@@CarbonsDIYGarage Thx CDIYG, I'm gonna need it.
Well, this might sound stupid but how did you get the coolant into the heater core through the hoses?
Not stupid! Jump to 9:36 in the video. You can see the green coolant going into the smaller/lower hose. Off camera, I'm pouring coolant (via funnel) into the hose (and holding the hose up) to push/get coolant into the heater core. You can see that coolant then comes out of the top hose, meaning the core is full.
But to answer your question - funnel into the hose off camera. (and I forgot how loud/annoying the lawn services were that day)
Sorry the video wasn't clear on that; thanks for watching.
@@CarbonsDIYGarage 😊 thank you
This guy went about flushing the heater core all wrong, the best thing to do is to leave the hoses attached to the heater core and disconnect them from the thermostat and block pull them up over the air intake, buy a standard garden hose adapter female end and connect hose from your house and flush for 45 seconds, then disconnect the garden hose attachment and place it in the return end and flush that way for 45 seconds after blowing out with compressed air or your mouth, the inset a funnel into the return side(larger hose) and pour enough white vinegar till it pours out the other end and let sit for 10 minutes, after repeat flush with water, then reattach hoses as normal and run engine to operating temperature should increase heat and engine will run slightly cooler, I gained almost 40 degrees in heat
Thanks for the comments! I dunno that there's that much difference from what you describe and what I did. I clearly didn't leave the hoses attached to the heater core, though I could have, like you suggested. Instead I just used my own, clear hoses. I'm not sure it makes a difference except I didn't clean out the small lengths of hose between the core and the t-stat and block. A hose adapter is definitely a good add and I'll be doing that if there's a next time. The hose sprayer did not work well.
The vinegar idea isn't something I've seen before. It sounds worth investigating since it works well for mineral deposits on home plumbing fixtures. Is it certain the acidic vinegar won't cause problems with the materials in the heater core?
I'm happy to report that with us being in cold December now, my TJ's heater temp output is way better than it was before I did the flush 11 months ago.
Thanks again for the video review.
@@CarbonsDIYGarage that additional water pressure could damage the heater core , so you're not off there. You need to pump distilled water in there and not tap water. The vinegar idea could breakup some rust in there, but if that's what you're doing , you need that core taken out and replacing it.
@@CarbonsDIYGarage I think most cooling system/radiator flush kits are basically vinegar or of the like. The water pressure is also an issue with hoses. You don't want to have to take out a dash to replace a heater core. It's miserable. I think the core is rated for around 13psi and garden hoses are probably around 40.
@@SeriouslyAwesome Great insights, Thanks - and thanks for watching.
Are you sure the top heater hose is the return? It looks like next to where it says "heater" on it, that it has a arrow pointing towards the firewall.
Yeah, I got the flow direction from the factory service manual. But I just went and looked at the hoses. Both actually say “heater” on them and the hose size. But no flow direction info. It would be great if they put flow arrows on them. Thanks for watching.
My upper gets hot Lower is cooler. I think the upper is the inlet.
Dang. Im impressed by all your projects. I am learning a lot from you. Question...How do you come up with these projects? Do you just go after items that you are having problems with? OR is there some master list of maintenance items that should be done?
Well, it's kind of both. Mostly it's just tackling projects as they come up. When I first got the Jeep it needed a LOT of work so I just made a long list, put them in priority order, and just worked them one at a time. Of course more things broke over time, so those got added to the list as well. There's also schedule maintenance like engine/diff/transfer oil case changes, filters, brakes, spark plugs, etc. Then there's just improvements I want to make, like the door jamb switches on the TJ or the suspension list on the JKU. Of course every time I seek a video on how to do something I come across others that "man, I should do that too" so it goes on the list.
Thanks for the video bud. Did this work for your heat issue?
The Jeep's my son's daily driver and he says the heat has been great all (south Texas) winter so far, so it looks like the flush did the trick.
Thanks for watching.
@Carbon's DIY Garage Yw. Thanks for the quick reply. Looks like I need to do this. Lol. Thank you for the links for the clamps and hoses. Will def make it easier. 😎👍
@@CarbonsDIYGarage why do you think it worked? If only a little debris came out...what do you think changed to improve the heat?
@@---rg1gb The passageways on these little cores/heat exchangers are small and easily blocked up. It wouldn't take a whole lot to start slowing the flow. At least that's my theory. It would be interesting if people commented on how much "junk" they get out of their core compared to how little heating they're getting.
Great Video... what about radiator flush is that coming soon?
Thanks for watching, art! So far the coolant system is working well and the coolant still looks green. A flush is on the list of things to do but probably not in the near future since TDSR has a few items that need to happen sooner than later.
I guess we'll all have to stay tuned and subscribed to see when the great flush happens. :)
By the way, if I had to do it again - and especially if I was flushing the whole system - I wouldn't use the hose sprayer. I'd get a nipple adapter for the hose so I could better regulate the amount and pressure of water going into the system. The sprayer worked fine for the little heater core but I don't think it'll work well for that bigger volume/job.
Ok cool ty. I gotta do a flush on mines because it looks all mucky.
Thanks for the video! Well...has it gotten cool enough for you yet to try out the heater? My son just got an 01 TJ, 2.5l for his first vehicle. Tried his heater last week and it was not hot at all. He has several other unrelated issues so this isn't a huge priority now, but still curious if this solved your problem. Enquiring minds want to know.
Thanks for the reminder! The Jeep's my son's daily driver and he says the heat has been great all winter so far, so it looks like the flush did the trick.
Thanks for watching and good luck with your 2.5L TJ!
(Our TJ is also my son's first vehicle)
Shawn Hudson I have a 2002 TJ 4.0 that also has a heater issue. It puts out warm air but not hot. The door mechanism runs when going from hot to cold and I flushed the heater core with no obvious debris coming out and no noticeable change in temperature. I am leaning towards the temperature control switch being faulty but am not certain. If you have found the problem on his Jeep I would appreciate knowing what it was. Thanks and good luck!
What are those doors you have on there? They look pretty robust.
Thanks for watching (and subscribing?), Jason! If you're talking about the doors on TDSR (e.g. 10:12), those are just the stock metal half doors. The upper doors are solid sliding glass windows vs. the more typical roll up plastic windows.
Have you turned the heater on to see if you're getting more heat?
I *think* the answer to your question is "yes." It felt a lot hotter when I tried it out, but it's also summer in south Texas so I'm not really sure. Real test probably won't come for another 3 months or so.
@@CarbonsDIYGarage temps should be at the floor duct (according to TJ service manual) 144* F on full heat, floor blower. my 2005 is at 100*, I need to do a heater core (already flushed core) replacement=big big job 😨
@@lorax1968 Ah, great! Thanks for that info - never thought to look for that in the service manual.
I have looked in the service manual on replacing the heater core and/or removing the a/c box - big job indeed! I've got a/c as well, making it even more complicated. Good luck on yours (and thanks for watching)!
What is TDRS?
Thanks for watching, Scott (and subscribing?)!
I have to LOL - TDRS is a typo. It should be TDSR (and I've now corrected it in the video description). TDSR is shorthand for the temporary name I've given to this Jeep (That Doesn't Sound Right). TDRS is an acronym I use often during my day job and clearly type it way too often so I didn't even notice my error.
@@CarbonsDIYGarage You actually got the acronym RIGHT in your comments section, I typed it wrong. Lol. Thanks for the clarification. And the video. I had no idea about the hose pliers.
just replace the heater core