How to: Quick and Easy 2nd gen Blend Door Replacement Tutorial

[marsjnj]

(Edited by Admin)

Information starts below this post.

 

[Pontisteve]

Well, I was going to upload the pics I took of my 98 limited anyway. I decided to try using a Weller portasol cordless butane soldering iron with a hot knife attachment. I only cut 3 sides, and then used a heat gun to soften the plastic and swing the plastic open like a hinge.

That worked well! The hinge and heat gun part. The hot knife blade was way too wide,and left a rather huge gap. That's exactly what I was hoping to avoid. A skinny hot knife blade may have worker better. I tried an exacto knife first, but it wouldn't cut through. Then I tried heating the exacto blade red hot, but it cooled off immediately. Then I tried the hot knife which has cut too wide. If there was a super think hot knife blade attachment, that would have worked better.

I had to cut additional material on either side of the hinge point, because I could not flex the box enough to get the door out. The heat gun didn't help that either. Just cut on both sides of the pivot without getting too close to the pivot. Then you can fold it down a little to get the door out.

The new door goes in without the top of the hinge installed. You install the top piece from the outside top of the box. You have a 50/50 chance of getting it in the right direction the first time, unless you can eyeball which way it can go.

I used a Dorman door kit that said it wouldn't fit automatic temp control. It fit just fine! Once I got the door installed, the electronic control wouldn't move the door. I had to use the writeup I found here to check codes and reset the controls. That worked, and the door now works right.

So I used the heat gun to fold the flap back up, and now I had to fix the 1/4" gap. I used a plastic welder I have, and added a bit of material as well, which came in my kit. A plastic welder amounts to a soldering iron with adjustable temperature, and a penny sized flat head that gets very warm. I just basically melted it back together and added material as necessary. The final finish looks similar to if I had wiped black Rtv silicone as smooth as possible with my finger. Not perfect, but much better than the mess I made with the hot knife.

 

[Pontisteve]

If I had to do it over again, I would cut the box open with one of those mini circular saw blades I get from harbor freight. They are super thin and look like a miniature skil saw blade that you use in a drill with an arbor. They're like 3 bucks with arbor and they're as thin as a business card, I think.Then I would patch it back up with the plastic welder, or black silicone or AC tape. I would not use a hot knife to open the box. I would cut 3 sides and use a heat gun to fold it open. That worked well.

 

[skydude]

Not the blend door -what can it be?

Thank you so much for this write up!
I hoped it would sort out my problems - it didn't - but atleast I have made the effort and the new door is in.
I posted my question on another thread regarding heater core replacement, but if there is anyone in here who has the time to weigh in, I'd be a very happy man.

Hi guys.
Question from a Norwegian here; I've had the pin-in-actuator (for the blend door) fix on my 98 Explorer (4L SOHC, 4x4) for a few years now but as it started getting cold last year, I couldn't get any heat from my ventilation system. I just assumed that the temporary fix had seen the end of its days so I moved along in the forum and found and did the blend door (Rock Auto) replacement through the bottom of the plenum. Before I sealed off the bottom I made sure that the new door worked, being able to see through the cracks.
However I am not getting any heat! I still seems like the door turns around its pivotpoint when I adjust the temperature (sound/tactile indications), there is no leak from underneath the plenum and the entire plenum is not getting warm at all... Any suggestions would be much appreciated. Chris

 

[Pontisteve]

The system is comprised of the Auto or manual A/C Controller, the blend door actuator, and the blend door itself. I would imagine the blend door itself is the most common problem, since the plastic hinge cracks and the actuator just spins inside the blend door.

The next most likely suspect is the blend door actuator. They're cheap enough to try one. In fact, I have one for sale. I put a new one in, and it didn't solve my problem, so I replaced the door and fixed it, then put the new actuator back in the box to resell and reinstalled the original actuator.

The actuator is only as good as what's controlling it electronically, so of course the controller could be bad. But it's less likely I think, and more expensive to replace.

One note. After fixing mine, I couldn't get the AC controller to move the blend door. It was like it had electronically given up. I even used my scantool to scan and clear codes, and it didn't help. I remembered reading something in this long thread about how to reset the actuator using some procedure outlined in this thread. I went back, found that document, printed it and followed it. I can't recall the details of what it was or how it worked, but it fixed it. Once I did that procedure, the blend door responded perfectly to the AC controls.

I believe this has something to do with the fact that the actuator is supposed to swing the door open and closed, and mark the positions of where open and closed max angles are. Then next time, it knows where to stop left and right. With a broken hinge, I believe it knows there is a problem because it never senses the hinge quits rotating. And once it knows that, I believe it no longer tries to control the door. So once you fix the door, you have to perform this little procedure to reset that. I mentioned it a while back in one of my posts. Try that.

 

[Pulaskiman]

I can't see the pictures. Anyone else having issues with this, or know how to see the photos?

Thanks

 

[DaExplorer]

Try looking at posts 73 a 75 of this thread. I took some photos and wrote a little about it.
Hope this helps.

 

[STAMUS25]

blend door replacement:

Today's test subject is a 1997 eddie bauer explorer. Hopefully yours will be somewhat similar.

I’m going to assume that you’ve correctly assessed the problem, and that your blend door indeed needs replaced.
You’ll come across all sorts of instructions on the internet for repairing your blend door. Forget them. It’s less than $10 for a replacement, and unless “you want fries with that” is part of your daily work routine, your time is worth more than the cost of a replacement.

http://www.napaonline.com/masterpag...10&description=heater+blend+door+repair+latch is the blend door from napa. Please check that that part is correct for your year and model before ordering.

I purchased the dorman replacement kit from rock auto, but for some reason it isn’t showing up online now. Maybe i got the last one, sorry.

The kit i received was really nice, with both a steel template for cutting the plenum to remove the blend door, and a self-adhesive steel panel to cover the hole when you’re done. The only problem is the kit assumes you’ve got access to the top of the plenum, and unless i’m mistaken, without a whole lot of work, that isn’t going to happen. It also looks like the replacement door is made out of abs, which should be a lot more durable than the cheap junk ford made the original door from.

What we’re going to do is do it the easy way (well, easier in any case), go in from the bottom.

First, let’s get that glove compartment out of the way. Open it, and squeeze in the sides so you can open it fully to access the hinge. Using a #20 torx bit, unscrew the 3 screws holding the hinge to the dashboard.

next, locate the blend door actuator on top of the plenum, and remove the plug going to it. Tuck the plug someplace where it’ll be out of the way, but where it’ll be accessible again later when you want to hook it back up.

Note: You really don’t have to remove the actuator if you know it’s working correctly, but it’ll be a lot easier to install the new blend door if you do. Otherwise you’ll have to insert the new blend door in a position that matches the direction of the actuator’s stud, which could prove tricky. We’ll just assume that you want to remove it. If not, skip ahead 4 sections, and have fun installing the replacement!

Depending on the year and possibly model/options, some folks have reported being able to pry the blend door actuator off of its mounting base. On my ’97 eddie, i found it quite easy to do so after the actuator had been removed from the plenum, but not such an easy thing while it was installed. If you can pry it up without damaging anything, great (skip the next 2 parts). If not, get yourself a 5/16 wrench and socket. I used a ratcheting offset screwdriver and a 5/16 socket, for the back i was able to get a slightly longer “great neck” brand 5/16 socket from autozone which gave me the extra clearance i needed, ymmv.

there are 2 bolts on the “front” side (facing the rear of the vehicle). One is easy. One is recessed behind part of the mounting base (hence the socket). The third is quite cruelly located on the opposite side of the actuator, where just about nothing can get to it. If you can, reach over the actuator and use your fingers to locate it, so you’ll know where the socket needs to get to. Once i got it aligned correctly on the bolt, i used one hand to keep downward pressure on the socket, to prevent it slipping off and assure that it was actually turning. I used the other hand to move the ratchet handle back and forth. There isn’t much room to do this, so if you can get one click per movement, you’re doing fine.

If you feel like it, keep doing this until the bolt is removed. Otherwise, after about 30 clicks, you should be able to pry up the front of the actuator, and either cut the bolt with a hacksaw blade, or any other implement of destruction you deem fit for the job. I don’t know anyone who’se ever considered putting that bolt back anyway.

okay, now that we’ve got the blend door actuator removed, plug its connector back in, and cycle back and forth between hot and cold, ensuring that the “d” shaped stud protruding from the bottom of the actuator moves when you do this. If it does, and there’s no clicking from the actuator, it might be in good enough shape to go back in. If it doesn’t move, either replace it, or check your wiring to make sure there isn’t some other problem. In my case, both my blend door was broken, and its actuator was shot (click, click, click went the stripped gears).

Finally, the moment you’ve all been waiting for; removal of the old blend door. Take a good look at the bottom of the plenum. The circular area which sticks down is where the bottom of the blend door shaft sits. By the somewhat triangular shape of the area around that, you should be able to judge where the door travels. We’re going to cut along the back edge (facing the front of the vehicle), the front edge (facing the rear of the vehicle), the small section between those two (facing the passenger side of the vehicle), around the shaft seat area, and partially along the last side (facing the driver’s side). We don’t want to completely cut that side, as we’re going to pry it down like a flap. This will make it easier to close when we’re ready to.

my weapon of choice is the roto-tool (dremel, craftsman, or whatever). I made a trip to sears, and picked up a general purpose cutting bit for $3.99. It’s similar to a drill bit, but works like the blade in a roto-zip, and once inserted, can be moved laterally to make the cuts we need.

start in the back (facing the front of the vehicle), towards the center and work towards you. There’s a crease in the plenum along the back edge, let this be your guide and carefully cut along it. Next, cut the front edge (facing the rear of the vehicle), again on the corner where the flat surface meets the vertical one. Then cut the remaining short edge between your first two cuts.
Carefully cut around the shaft seat, going about 1/3rd of the way towards the back (front of the vehicle) edge. At this point, see if you can bend down the flap like in the picture. If not, start at the back corner (front of the vehicle), and cut back towards you until you can.

Once you can pry the flap down, you should be able to reach in and remove the old blend door. Feel around for any broken bits (never found mine) and remove any small plastic pieces left from your cutting (otherwise they’ll just blow all over you vehicle when you next turn on the air).

old broken blend door

the old and new blend doors side by side

insert the new blend door, large circular part upward. I found it easier if i put one hand over the hole on the top of theplenum, then i could tell when the new blend door was properly aligned. Slip the bottom stud into its seat. Rotate the blend door towards the front of the vehicle as far as it will go. This will put it into an alignment where it should be out of our way when we re-secure our flap. Push the flap back up into its original position, and secure it with a few thin strips of duct tape.

Now we just need to seal it into its original position. There are a variety of different ways to do this, from epoxy to silicon to fiberglass to just plain duct tape, but i wanted something that would be fairly rigid when done, wouldn’t need replaced, wasn’t too messy to work with, and didn’t take forever to cure. I selected quickseal plastic repair putty, jb weld makes a similar product, both claim to cure in 4 hours.

i opted to take a 2-stage approach to sealing the flap. I didn’t want to get much of the putty on the inside of the plenum where it might hinder the movement of the blend door. I also wanted to be sure i got the flap back in its original position. You could probably seal it back up in one shot if you’re careful.

as seen in the photo, i sealed most of 2 sides, with the duct tape strips holding the flap in place. Once that cured, i removed the duct tape and filled in the rest of the holes. As the whole shebang will be hidden behind the glove compartment, there’s no need to make it look pretty, as long as it’s functional, you’ve done the job.

Once your adhesive has cured, replace the blend door actuator. You may need to hook up the wires and cycle it back and forth between hot and cold a few times to correctly align the actuator stud with the blend door. Once that’s done, screw it back in place (or pop it back in its holder if you were able to pry it out without unbolting it), and check for proper operation of your hvac unit. You should have hot heat, and cold air, and everything in between.

Altogether, aside from the sealant curing time, it should take less than an hour to do the whole job. Under $20 worth of parts sure beats $1400 at the stealership.

great write up

 

[Northwest1]

I am very impressed with your detailed "from the bottom" repair approach. I have purchased the door from Napa and am excited to give your tutorial a go!! I have been running "full heat" all winter and now that spring is on the doorstep would love to get this repaired. I had assumed the actuator had failed.... but after removing and testing it works as required. Therefore, I have to assume that the door itself is stuck/broken/dis-attached.

However the images from your posted on April 2008....have broken links on the forum today. As your images would be a Huge benefit...is there a way that the images can be reposted for my (everyone's) benefit?

Blend door replacement:

Today's test subject is a 1997 Eddie Bauer Explorer. Hopefully yours will be somewhat similar.

I’m going to assume that you’ve correctly assessed the problem, and that your blend door indeed needs replaced.
You’ll come across all sorts of instructions on the internet for repairing your blend door. Forget them. It’s less than $10 for a replacement, and unless “you want fries with that” is part of your daily work routine, your time is worth more than the cost of a replacement.

http://www.napaonline.com/MasterPag...10&Description=Heater+Blend+Door+Repair+Latch is the blend door from Napa. Please check that that part is correct for your year and model before ordering.

I purchased the Dorman replacement kit from Rock Auto, but for some reason it isn’t showing up online now. Maybe I got the last one, sorry.

The kit I received was really nice, with both a steel template for cutting the plenum to remove the blend door, and a self-adhesive steel panel to cover the hole when you’re done. The only problem is the kit assumes you’ve got access to the top of the plenum, and unless I’m mistaken, without a WHOLE lot of work, that isn’t going to happen. It also looks like the replacement door is made out of ABS, which should be a lot more durable than the cheap junk Ford made the original door from.

What we’re going to do is do it the easy way (well, easier in any case), go in from the bottom.

First, let’s get that glove compartment out of the way. Open it, and squeeze in the sides so you can open it fully to access the hinge. Using a #20 torx bit, unscrew the 3 screws holding the hinge to the dashboard.

Next, locate the blend door actuator on top of the plenum, and remove the plug going to it. Tuck the plug someplace where it’ll be out of the way, but where it’ll be accessible again later when you want to hook it back up.

NOTE: You really don’t have to remove the actuator if you know it’s working correctly, but it’ll be a LOT easier to install the new blend door if you do. Otherwise you’ll have to insert the new blend door in a position that matches the direction of the actuator’s stud, which could prove tricky. We’ll just assume that you want to remove it. If not, skip ahead 4 sections, and have fun installing the replacement!

Depending on the year and possibly model/options, some folks have reported being able to pry the blend door actuator off of its mounting base. On my ’97 Eddie, I found it quite easy to do so after the actuator had been removed from the plenum, but not such an easy thing while it was installed. If you can pry it up without damaging anything, great (skip the next 2 parts). If not, get yourself a 5/16 wrench and socket. I used a ratcheting offset screwdriver and a 5/16 socket, for the back I was able to get a slightly longer “Great Neck” brand 5/16 socket from AutoZone which gave me the extra clearance I needed, YMMV.

There are 2 bolts on the “front” side (facing the rear of the vehicle). One is easy. One is recessed behind part of the mounting base (hence the socket). The third is quite cruelly located on the opposite side of the actuator, where just about nothing can get to it. If you can, reach over the actuator and use your fingers to locate it, so you’ll know where the socket needs to get to. Once I got it aligned correctly on the bolt, I used one hand to keep downward pressure on the socket, to prevent it slipping off and assure that it was actually turning. I used the other hand to move the ratchet handle back and forth. There isn’t much room to do this, so if you can get one click per movement, you’re doing fine.

If you feel like it, keep doing this until the bolt is removed. Otherwise, after about 30 clicks, you should be able to pry up the front of the actuator, and either cut the bolt with a hacksaw blade, or any other implement of destruction you deem fit for the job. I don’t know anyone who’se ever considered putting that bolt back anyway.

Okay, now that we’ve got the blend door actuator removed, plug its connector back in, and cycle back and forth between hot and cold, ensuring that the “D” shaped stud protruding from the bottom of the actuator moves when you do this. If it does, and there’s no clicking from the actuator, it might be in good enough shape to go back in. If it doesn’t move, either replace it, or check your wiring to make sure there isn’t some other problem. In my case, both my blend door was broken, and its actuator was shot (click, click, click went the stripped gears).

Finally, the moment you’ve all been waiting for; Removal of the old blend door. Take a good look at the bottom of the plenum. The circular area which sticks down is where the bottom of the blend door shaft sits. By the somewhat triangular shape of the area around that, you should be able to judge where the door travels. We’re going to cut along the back edge (facing the front of the vehicle), the front edge (facing the rear of the vehicle), the small section between those two (facing the passenger side of the vehicle), around the shaft seat area, and partially along the last side (facing the driver’s side). We don’t want to completely cut that side, as we’re going to pry it down like a flap. This will make it easier to close when we’re ready to.

My weapon of choice is the roto-tool (Dremel, Craftsman, or whatever). I made a trip to Sears, and picked up a general purpose cutting bit for $3.99. It’s similar to a drill bit, but works like the blade in a roto-zip, and once inserted, can be moved laterally to make the cuts we need.

Start in the back (facing the front of the vehicle), towards the center and work towards you. There’s a crease in the plenum along the back edge, let this be your guide and carefully cut along it. Next, cut the front edge (facing the rear of the vehicle), again on the corner where the flat surface meets the vertical one. Then cut the remaining short edge between your first two cuts.
Carefully cut around the shaft seat, going about 1/3rd of the way towards the back (front of the vehicle) edge. At this point, see if you can bend down the flap like in the picture. If not, start at the back corner (front of the vehicle), and cut back towards you until you can.

Once you can pry the flap down, you should be able to reach in and remove the old blend door. Feel around for any broken bits (never found mine) and remove any small plastic pieces left from your cutting (otherwise they’ll just blow all over you vehicle when you next turn on the air).

Old Broken Blend Door

The old and new Blend Doors side by side

Insert the new blend door, large circular part upward. I found it easier if I put one hand over the hole on the top of theplenum, then I could tell when the new blend door was properly aligned. Slip the bottom stud into its seat. Rotate the blend door towards the front of the vehicle as far as it will go. This will put it into an alignment where it should be out of our way when we re-secure our flap. Push the flap back up into its original position, and secure it with a few thin strips of duct tape.

Now we just need to seal it into its original position. There are a variety of different ways to do this, from epoxy to silicon to fiberglass to just plain duct tape, but I wanted something that would be fairly rigid when done, wouldn’t need replaced, wasn’t too messy to work with, and didn’t take forever to cure. I selected QuickSeal Plastic Repair Putty, JB Weld makes a similar product, both claim to cure in 4 hours.

I opted to take a 2-stage approach to sealing the flap. I didn’t want to get much of the putty on the inside of the plenum where it might hinder the movement of the blend door. I also wanted to be sure I got the flap back in its original position. You could probably seal it back up in one shot if you’re careful.

As seen in the photo, I sealed most of 2 sides, with the duct tape strips holding the flap in place. Once that cured, I removed the duct tape and filled in the rest of the holes. As the whole shebang will be hidden behind the glove compartment, there’s no need to make it look pretty, as long as it’s functional, you’ve done the job.

Once your adhesive has cured, replace the blend door actuator. You may need to hook up the wires and cycle it back and forth between hot and cold a few times to correctly align the actuator stud with the blend door. Once that’s done, screw it back in place (or pop it back in its holder if you were able to pry it out without unbolting it), and check for proper operation of your HVAC unit. You should have hot heat, and cold air, and everything in between.

Altogether, aside from the sealant curing time, it should take less than an hour to do the whole job. Under $20 worth of parts sure beats $1400 at the stealership.

 

[Northwest1]

3 of 3


Hope this helps someone.

Dan Thanks for posting these images I am now eager to "cut my way in!"

 

[Nate_V8]

I'm dragging this up from the dead as I also have a broken blend door. How to do it looks easy enough but I'm ordering from rock auto and there are 2 part numbers.

I have an explorer 5.0 with manual controls.

Which one?

DORMAN 902202
https://www.rockauto.com/en/moreinfo.php?pk=1147163&cc=1304435

or

902221
https://www.rockauto.com/en/moreinfo.php?pk=3386019&cc=1304435

 

[mbruffey]

It's okay to wake up the thread. I have needed to do mine for several years and hope now to have time to do it in the next few weeks. I cannot answer the "which door" question--yet. I have the one with the metal reinforcement. We'll see.

My question is about the glue. Several have glued the duct back together with epoxies, I noticed. But epoxy usually softens with heat. I wonder if the old Testor's model cement would work on this plastic. What type of plastic is this duct, in fact? Thx, M

 

[Nate_V8]

It's okay to wake up the thread. I have needed to do mine for several years and hope now to have time to do it in the next few weeks. I cannot answer the "which door" question--yet. I have the one with the metal reinforcement. We'll see.

My question is about the glue. Several have glued the duct back together with epoxies, I noticed. But epoxy usually softens with heat. I wonder if the old Testor's model cement would work on this plastic. What type of plastic is this duct, in fact? Thx, M

I read some people used a soldering gun to melt the plastic together. Someone mentioned on the last page that it was olefin plastic but I can't confirm if that is what it is.


Anybody know what Dorman part number to order from my post?

 

[avgguy6]

Waiting for actuator for my '99 Eddie Bauer with EATC. Removed actuator by removing two easy access screws in front, pryed actuator up enough to get reciprocal saw hacksaw blade in to cut ridiculous back screw.Cut area below per instructions posted here, removed old blend door. Much to my delight, with door removed I now have air or heat. No temp adjustment other than full heat or full air, which is what I generally use anyway, only adjusting fan speed for comfort.
I will install new door and acctuator, just because..

.

 

[avgguy6]

It's okay to wake up the thread. I have needed to do mine for several years and hope now to have time to do it in the next few weeks. I cannot answer the "which door" question--yet. I have the one with the metal reinforcement. We'll see.

My question is about the glue. Several have glued the duct back together with epoxies, I noticed. But epoxy usually softens with heat. I wonder if the old Testor's model cement would work on this plastic. What type of plastic is this duct, in fact? Thx, M

It's okay to wake up the thread. I have needed to do mine for several years and hope now to have time to do it in the next few weeks. I cannot answer the "which door" question--yet. I have the one with the metal reinforcement. We'll see.

My question is about the glue. Several have glued the duct back together with epoxies, I noticed. But epoxy usually softens with heat. I wonder if the old Testor's model cement would work on this plastic. What type of plastic is this duct, in fact? Thx, M

Use JB WELD Epoxy.

 

[mbruffey]

OK. Thanks for suggestion of JB Weld. m

 

[Smokeblower]

I can't say enough for the quality of the help on this thread. I had to replace both the door and the actuator on my 98 Explorer EB. Working fine now and couldn't even have begun without your help.

 

[Smokeblower]

Thank you to everyone on this thread and particularly to Magicland and DaExplorer for the great walk-throughs and photos. Replaced my blend door with the Dorman kit then had to replace the actuator too. I am not as precise a carver of plastic as the photos I saw, but it works, seems solid and isn't leaking air where I patched it up. What a great resource this forum is! Next up, replacing the blown Mach subwoofer.

 

[Brem95]

What’s the fix for broken pivot points? Thanks

 

[97 EBONY X PREDATOR]

I am very impressed with your detailed "from the bottom" repair approach. I have purchased the door from Napa and am excited to give your tutorial a go!! I have been running "full heat" all winter and now that spring is on the doorstep would love to get this repaired. I had assumed the actuator had failed.... but after removing and testing it works as required. Therefore, I have to assume that the door itself is stuck/broken/dis-attached.

However the images from your posted on April 2008....have broken links on the forum today. As your images would be a Huge benefit...is there a way that the images can be reposted for my (everyone's) benefit?

I just used a Stanley knife to cut out a triangle in the bottom of the heater box to make a pulldown flap to access the blend door.
Found the top axle Shaft broken off.
I'm using a epoxy resin with a strength of 75kg per sqr cm.
Then reinforced with metal plating to give the axle mount maximum strength so it won't break from the stress of the actuator motor again.
Pop the door back in through the flap. Line up top axle with actuator hole wrestle the bottom of axle into the bottom hole.
Tape up the flap you cut out temporarily
Center the climate control switch with actuator hooked back up but not in place.
Once centred lift actuator motor back were it goes then using climate control switch to line up the shafts and actuator will slot in properly install removed screws test system out if all is well time to seal of the access flap you made using any epoxy weld or glue designed to withstand heat.
Job done you now have heat and AC working again.