How to: 2nd Gen Blend Door Quick Fix

[SoNic67]

No, it is not... And don't try the Dorman "auto" ones, they didn't work on my automatic.

 

[dhvaughan]

My blend door was broken at the top of the pivot shaft and would no longer move. After reading the Heater Treater site, and several threads on this site, I was able to permanently fix it with the Dorman replacement door, working through a hole cut in the bottom.

Installing the new door was tricky, and required removing the aluminum D-piece from the top of the pivot shaft, and inserting it onto the motor shaft. then reassembling inside the plenum box.

It turned out to be pretty easy. Well, maybe not easy, but do-able.
Here's my contribution back:

I replaced the broken factory blend door in my 98 ford explorer using Dorman part number 902-221, working only through, and under, the glove box. It was a tough job and I worked on it 2 evenings. It took twice as long as it should have, and I almost gave up after the first evening, and would have given up without the tip below of separating the aluminum top piece from the plastic/nylon shaft.

1. unplug and remove the blend door motor, by prying underneath with a large screwdriver while squeezing the push clamps. there are 4 push clamps. set it aside.

2. mark the bottom plate and cut out the triangle. cut VERY CLOSE right up to the bottom pivot point. its important to come right up to the round pivot point, because you're going to have to cut the vertical shaft to get the old door out.

3. when removing the original blend door, unless the pivot shaft is completely broken in two, its difficult to get the old door out, because its captured in the upper and lower pivot points. therefore, you must cut the vertical shaft with the dremel, or a small mini hacksaw blade. BE EXTREMELY CAREFUL - as the AC EVAP CORE IS DIRECTLY BEHIND THAT PIVOT SHAFT. you can't see it, but you can feel it with your hand. clip the shaft as LOW AS POSSIBLE at the bottom pivot point, and DO NOT extend the tool into the AC EVAP.

4. thoroughly clean out the bottom pivot point of all broken plastic, chips, etc.

5. reassembly. this is the hard part. do it like this.
use a sharpie and mark a line on the aluminum piece to indicate the position of the door. this is necessary to reassemble it correctly later.

separate the aluminum top piece from the plastic shaft. place the aluminum piece in a vise, and gently rock the plastic shaft. as soon as a space opens up, insert a flat screwdriver and pry a little.

note that the inner opening of the aluminum piece is oval, and that it can be reinstalled in 2 postions. the correct way, and 180 degrees off, which will be major problem.

test fit the door into the opening. position it about the halfway point of the pivot arc.

connect the electrical connector to the blend door motor, turn the ignition on. turn the heater on, and set the temperature dial to cold, then hot. observe blend door motor shaft turning. set the temperature to the mid-point. turn ignition off. disconnect electrical connector.

Do not reinstall the aluminum piece onto the blend door. Instead - Install the aluminum piece onto the blend door motor shaft. it will only go one way.

Patiently maneuver the motor and aluminum piece into the top of the plenum housing. electrical connector must point towards rear of vehicle. it will fit, but its takes a lot of different moves to work it in. eventually it will drop into the hole.

with your left hand on the motor, and your right hand on the blend door, holding it at about the midpoint of the arc, slip the aluminum shaft piece over the plastic shaft piece. once aligned, press the motor down over the 4 clips. press up firmly on the blend door.

connect electrical connector, turn ignition on, turn heater on. rotate temperature dial between cold and hot several times and verify the blend door is functioning properly.

reseal the cutout in the bottom of the plenum. i used 3 small pieces of duct tape to hold it in place temporarily, and filled in the exposed seam with black RTV. when cured, remove duct tape and fill remaining seams where duct tape was.

conclusion-
I was on the verge of returning this part and buying the more expensive Heater Treater which provides a spring loaded bottom pivot point to avoid all the the crap above. However, once I moved the aluminum piece from the blend door to the motor, it all came together and without any more trouble.

 

[yellow02]

heater blend doors on early 2002 Explorer Sport

Suddenly no heat, only cold air. Blower is OK. Vent selection is OK. A/C is OK. This is a Manual Selection system. Been thru the HeaterTreater info. Dealer wants $$$$ to pull entire dash and track/repair possible actuator motor/blend doors located behind driver side dash next to gas peddle. An experienced independent tech who has fixed this problem many times agrees its the actuator on the driver side.

On mine there also is an actuator/blend doors right behind passenger side glove box (easy access for R/R) but this one works fine (I can hear the doors moving when rotating temp dial between cold and hot several times; and I hear NOTHING when I disconnect actuator cable...thus confirming actuator is operational). How many actuators/doors are in my Sport? Which one is not working? Any how-to video on R/R the one on the driver side by the gas peddle w/o pulling the whole dash, as has been suggested? Maybe the problem has nothing to do with any of the above?

I've been told my 2002 Sport is an early one and has much of the 2001 Explorer heater/AC/blower set up. Also I do not have a full console between front seats.

Thanks for any input. Jim

 

[jimandnena]

Manual control of the blend door

OK, I got my turn to tackle this beast. Tried the Dorman 604-202, blew a fuse in the message console. Exchanged it for a Dorman 604-217 according to the fit listed on Dorman's website. Blend door doesn't move.
In the meantime, here is my "fix" for getting hot or warm or cold air. The cover must be snapped on to hold the whole thing together but it works great for now.

https://picasaweb.google.com/jimand...PkhunuqQE&feat=directlink#5821255398651444082

I ran the EATC self test and got blend door failure so I'm sure if I get the right actuator I'll be set. The blend door works perfectly.
jim

 

[jimandnena]

OK, I got my turn to tackle this beast. Tried the Dorman 604-202, blew a fuse in the message console. Exchanged it for a Dorman 604-217 according to the fit listed on Dorman's website. Blend door doesn't move.
In the meantime, here is my "fix" for getting hot or warm or cold air. The cover must be snapped on to hold the whole thing together but it works great for now.

https://picasaweb.google.com/jimand...PkhunuqQE&feat=directlink#5821255398651444082

I ran the EATC self test and got blend door failure so I'm sure if I get the right actuator I'll be set. The blend door works perfectly.
jim

Got the correct actuator, 3rd try. Ordered from Amazon using Ford's part number: F77Z 19E616-BA. The package arrived with a label inside that had the Motorcraft part number YH-1758. Installed and working perfectly.

 

[yellow02]

Thanks for your suggestion but it doesn't apply here because my actuator works OK...confirmed by Ford dealer. The door axle is somehow broken so doors won't swing when actuator operates. Need to figure a way to manually operate doors.
Jim

 

[jimandnena]

Thanks for your suggestion but it doesn't apply here because my actuator works OK...confirmed by Ford dealer. The door axle is somehow broken so doors won't swing when actuator operates. Need to figure a way to manually operate doors.
Jim

Yes, a broken blend door is a whole other problem and solutions are listed at the beginning of this long discussion. I was "lucky" that it was only the actuator. Cutting into the heater box below the actuator is the only affordable way I know to fix a broken door.
jim

 

[yellow02]

Today confirmed both the actuator AND blend door work OK. SO...now looking for another reason I get NO HEAT. Blower, vent selection and A/C all work OK.
Just NO HEAT no matter the blend door position. Heater core is always cold.

Any ideas? Thanks.
Jim

 

[96eb96]

Today confirmed both the actuator AND blend door work OK. SO...now looking for another reason I get NO HEAT. Blower, vent selection and A/C all work OK.
Just NO HEAT no matter the blend door position. Heater core is always cold.

Any ideas? Thanks.
Jim

There is a vacuum controlled "heater control valve" that is inline with your heater tubes under the hood. May be worth a look...

 

[yellow02]

heater control valve 02 Explorer Sport

Thank you 96eb96

How do I check if the vacuum controlled "heater control valve" is working?
You say vacuum controlled "heater control valve" is inline with the heater hose. I see hoses right on top under the hood. And what appears to be vacuum hose at "T" connection to one of the heater hoses...is that it? '02 Ford Explorer Sport (2-dr), 4.0 V6 engine.

Local tech shop (experienced and reputable) again says its the heater box...needs to be replaced for over $1200. Not in the budget.
Thanks for any help Jim

 

[jimandnena]

Thank you 96eb96

How do I check if the vacuum controlled "heater control valve" is working?
You say vacuum controlled "heater control valve" is inline with the heater hose. I see hoses right on top under the hood. And what appears to be vacuum hose at "T" connection to one of the heater hoses...is that it? '02 Ford Explorer Sport (2-dr), 4.0 V6 engine.

Local tech shop (experienced and reputable) again says its the heater box...needs to be replaced for over $1200. Not in the budget.
Thanks for any help Jim

I think I found a photo in another thread
http://www.explorerforum.com/forums/showthread.php?t=370504
The lever on the valve should move when going from hot to cold.
HTH
jim

 

[greg s]

I will just add my take on the door replacement. I followed dhvaughan's method but with a few changes and I also used the 902-221 door from Dorman with the aluminum top piece. What I found that worked the best for cutting the heater box was one of the multifunction oscillating tools because you can set the blade at any angle allowing you to get in the limited space under the heater box. I only cut the sides and short area by the pivot and left the back edge uncut for the heater box. Then I used a heat gun to warm up the back edge and bent the flap down. My door was also still held in place by part of the top pivot and wouldnt come out easily. So I used the oscilating tool by pointing the blade toward the rear, and using it upside down I was able to hook it inside the heater box and cut off the lower pivot. I tried to remove the aluminum pivot on the new door but it seemed glued on and wouldnt budge. So instead I used a file to round off the top edge of the pivot to make it easier to slide in place and put a dab of grease on it. Then I put the bottom pivot in place and rocked the door in place without a problem. Finally I used the heat gun again to warm up the back edge and bent the bottom piece back in place and used the supplied tape to seal it back up. The oscillating tool was what made it easy to do and it doesnt make a big gap when it cuts. Total time for me was about 45 minutes.

 

[TJFoxx]

Thank you for this. The weather here has been freezing, and this was a very quick fix! (After I bought a new Dremel tool--my old on (20 years or so) gave up the ghost...)

 

[jimandnena]

I will just add my take on the door replacement. I followed dhvaughan's method but with a few changes and I also used the 902-221 door from Dorman with the aluminum top piece. What I found that worked the best for cutting the heater box was one of the multifunction oscillating tools because you can set the blade at any angle allowing you to get in the limited space under the heater box. I only cut the sides and short area by the pivot and left the back edge uncut for the heater box. Then I used a heat gun to warm up the back edge and bent the flap down. My door was also still held in place by part of the top pivot and wouldnt come out easily. So I used the oscilating tool by pointing the blade toward the rear, and using it upside down I was able to hook it inside the heater box and cut off the lower pivot. I tried to remove the aluminum pivot on the new door but it seemed glued on and wouldnt budge. So instead I used a file to round off the top edge of the pivot to make it easier to slide in place and put a dab of grease on it. Then I put the bottom pivot in place and rocked the door in place without a problem. Finally I used the heat gun again to warm up the back edge and bent the bottom piece back in place and used the supplied tape to seal it back up. The oscillating tool was what made it easy to do and it doesnt make a big gap when it cuts. Total time for me was about 45 minutes.

I second the vote on using a MultiMate type saw. I didn't have to remove the blend door but getting my failed actuator out was made easier when I cut some plastic structure above it that was preventing me from getting a hand back far enough to remove the mounting screws.
Another help was getting a dogbone style ratchet 1/4 and 3/8 drive combo, more compact than my 1/4 drive ratchet. One last tip, wrap a rubber band several times around the 7 MM socket to make it easier to hold for the ratchet to work.
1997 Explorer Limited EATC

 

[mattnoell]

for those of you who like me, dont want to shell out 1200$ to fix this blend door issue, you can do this. im writing it in as simple a way as i can for those, who like me, arent very mechanically inclined.

open glove box, and push the sides in to drop the box down as far as possible. you will see a big black plastic box. inside of that box is the blend door, and your heater core (looks like a miniture radiator).

take a razor knife and on the farthest left side of that box, cut a square hole big enough to get your hand in (only cut 3 sides of the square though so that you can just bend the plastic down out of your way and put it back in place when finished). now that it's open, you can see the heater core, but not the blend door. the blend door is located around the back left side of the heater core. reach your right hand in, with your thumb down, so the palm of your hand is facing the passenger side of the truck. when you reach behind the heater core, you will feel the blend door, and you can swing it open or closed. if you want your air conditioning to work, open the door all the way. if you want your heat to work, close the door all the way. after you have adjusted the door how you want it, blend the plastic you cut to get your hand in, back to it's normal position and tape it up with some duct or thick masking tape.

unfortunatley you can only have hot or cold doing it this way, but it saves you 1200$ and a lot of headaches trying to fix this by pulling the dash.

for where i live, i need only a.c. in the summer, and only heat in the winter, so i just go in and change the door position twice a year. the original job takes about 5 minutes, then at the beginning of summer or winter when i go in to change the door position, it takes me about 3 minutes, and most of that time is spent removing the tape and retaping it.

i hope this helps someone.

 

[mgar123]

blend door won't move

Hi there, I'm new to this forum. I heard the clicking noise for a while, but when it stopped so did the heat. I found the fix at the beginning of this thread and tried that last night....

I dropped the glove box and cut the black box behind it.

I can reach around behind the heater core and feel the blend door. However it doesn't seem to move. It feels like it's stuck maybe even half open, maybe it's just hard to move. I didn't want to force it and break something else. Am I supposed to be pushing or pulling the blend door in order to close it for the heat to work? Is it supposed to be hard to move or could there be something else going on?

Thanks for your help. Mike

 

[jimandnena]

Hi there, I'm new to this forum. I heard the clicking noise for a while, but when it stopped so did the heat. I found the fix at the beginning of this thread and tried that last night....

I dropped the glove box and cut the black box behind it.

I can reach around behind the heater core and feel the blend door. However it doesn't seem to move. It feels like it's stuck maybe even half open, maybe it's just hard to move. I didn't want to force it and break something else. Am I supposed to be pushing or pulling the blend door in order to close it for the heat to work? Is it supposed to be hard to move or could there be something else going on?

Thanks for your help. Mike

Hi Mike, sounds like the actuator on top of the heater box has stopped in the cold position. My blend door was fine, the actuator stopped working when the system was set for AC. Remove the actuator. That should let the door swing freely.
jim

 

[cparker741]

Different Problem with heater Door full open or full closed

96 Explorer, I either have full heat or full cold. That is when you position the temperature control at cold, it is cold, as you turn it up, it does nothing until passing through the 12 o'clock position at which time it goes to full heat. Turn it back to cold and it goes full cold, no mixing, seems that the door is full open or full closed. Any ideas what it is, obviously the motor works, just no intermediate positioning. Any ideas on the problem?

 

[tamie]

OMG this is a lifesaver!!

THANK YOU!

Tami

 

[tamie]

What happens if you cut white hose.....