SSM 49264 - Climate Control Temperature Will Not Adjust With Clicking/Snapping Noise From The Dash

[rrwhitman]

I couldn't actually feel the play since the bellcrank is pretty much hidden behind the actuator when it is in place. I am making an assumption that by tightening the bellcrank against the white lever it will reduce the possibility of the pin jumping out of the slot. I used two nylon washers, both about 1 inch OD. One of them has an ID large enough to clear a small raised cyclindrical boss in the actuator case where the shaft exits and the other has a slightly smaller ID, just large enough for the splined shaft. I am afraid I didn't make note of the exact dimensions - I brought the actuator with me to a hardware store and selected ones that fit my purpose by trial. In any case, when the bellcrank is slid onto the shaft it now bears against the outer washer, which I lightly greased, and is about 1/16 proud of where it would otherwise be. This is admittedly an experiment - I'll follow up.

Sponsored

 

[rrwhitman]

Also, the splined shaft of the bell crank is not a tight, press fit onto the shaft of the actuator. There is a small amount of play which allows the bell crank to slightly move/rock out of parallel alignment. At the outer edge of the bell crank that slight movement is amplified and could result in the pin being closer to escaping the slot. With the end of the bell crank shaft bearing against the nylon washer, it reduces that tendency. That's my hope at least.

 

[Blue Streak]

Added two nylon washers between the blue cam and the body of the actuator which moved the cam out about 1/16 inch and tightened it up against the white lever/pin. Back together and working - will post if the pin jumps out of the slot in the future. At least I have heat - 20's in the a.m.

It's bin like a month & no word. I assume all is working just fine. Just an update would be good. ? I need a project come spring.

 

[rrwhitman]

So far so good even though the temperature has been set mostly on heat. When I've turned the heat down I've moved the selector little by little, thinking that moving the mechanism slowly would perhaps lessen the chance of the pin jumping out of the slot. I don't know if that's true or not but I figured treating it gingerly can't hurt.

 

[Blue Streak]

Just an update. I can verify some type of binding. The other day the ambient temp was in the mid 50s. I had to run an errand & upon leaving I did not adjust the temp from max setting to maybe midrange ( brain fart did not think of it). While driving it did get rather warm in the truck. When I arrived at my destination I went to adjust the temp down ( so I would not forget again) With my DIY manual temp control the blend door was very hard to move so I waited till I got back in from my shopping. Again tried to adjust blend which moved very easy after cooling down. So I believe there is some kind of binding upon heat up. I have adjusted it in the past with no effort or binding. I will be more diligent on checking now.

 

[rrwhitman]

Just an update. I can verify some type of binding. The other day the ambient temp was in the mid 50s. I had to run an errand & upon leaving I did not adjust the temp from max setting to maybe midrange ( brain fart did not think of it). While driving it did get rather warm in the truck. When I arrived at my destination I went to adjust the temp down ( so I would not forget again) With my DIY manual temp control the blend door was very hard to move so I waited till I got back in from my shopping. Again tried to adjust blend which moved very easy after cooling down. So I believe there is some kind of binding upon heat up. I have adjusted it in the past with no effort or binding. I will be more diligent on checking now.

Good observation. When my blend door pin jumped out of the slot it had been on max heat for quite a while and everything was very warm in the truck. When I spun the selector all the way to cold that is when I heard the mechanism come apart and the clicking/thumping. That experience seems consistent with binding occurring when the heater box is hot (presumably the plastic is soft and deforms, creating the binding.) I've had no problems since shimming my unit to be tighter. I've continued to make any adjustments in temperature little by little just to be safe. Cheers.

 

[Blue Streak]

Good observation. When my blend door pin jumped out of the slot it had been on max heat for quite a while and everything was very warm in the truck. When I spun the selector all the way to cold that is when I heard the mechanism come apart and the clicking/thumping. That experience seems consistent with binding occurring when the heater box is hot (presumably the plastic is soft and deforms, creating the binding.) I've had no problems since shimming my unit to be tighter. I've continued to make any adjustments in temperature little by little just to be safe. Cheers.

Good to hear. I believe you are on the correct path. I am going to do the shimming this spring. I think minor adjustments slowly will work & never when on max heat. Allowing to cool some before adjusting cooler. This forum is great.

 

[rrwhitman]

Yes, these types of forums are invaluable. It is crazy that if you are just an uninformed truck owner, and you roll into Ford saying you have no heat, the fix is 3000-4000 dollars and takes tearing the whole truck apart - all because of the alignment of a 1/4 inch long pin coming out of a slot. The information on forums, and the ability to do things yourself, can save 1000's.

 

[Kemo Sabe]

Yes, these types of forums are invaluable. It is crazy that if you are just an uninformed truck owner, and you roll into Ford saying you have no heat, the fix is 3000-4000 dollars and takes tearing the whole truck apart - all because of the alignment of a 1/4 inch long pin coming out of a slot. The information on forums, and the ability to do things yourself, can save 1000's.

yeah, but I still don’t know how to fix blend doors. Are there videos?
I sure don’t want to pay 3-4k$! I do have extended warranty, if that works.
Thanks.

 

[rrwhitman]

Hello - as described in this and other threads fixing the problem can involve taking things apart, replacing the actuator if it is damaged, putting it back together and hoping it doesn't happen again, replacing the the actuator with a manual control (like Blue Streak), shimming the bell crank on the actuator to tighten it up against the blend door lever (as I did) to lessen the chance of it misaligning, or completely taking the truck apart and the replacing the heater box with a new one that doesn't deform. Getting to the actuators is fairly easy on the passenger side but if you have the system with separate blend doors for the driver and passenger, the driver's side is much more difficult to access. In any case, according to Ford the only correct repair is a complete heater box replacement that requires a shocking amount of disassembly of the truck. My truck was out of warranty and I did not want to bear the cost or the collateral damage of disassembling the truck to that extent. If your truck is under warranty I would take advantage of the warranty, though. Good luck!

 

[Motorpsychology]

yeah, but I still don’t know how to fix blend doors. Are there videos?
I sure don’t want to pay 3-4k$! I do have extended warranty, if that works.
Thanks.

Your Extended Warranty documents will show what is, and is not covered and for how long. If you service your truck at the same dealer where you bought the warranty, they'll have it on file. If you bought it online, contact them through their support or chat bot to learn what specifically is covered.

 

[Cmar]

Honestly Ford has had this issue since the 90's Explorer days, why they can't get it right I don't know. Mine does it too, but at least everything still works, albeit with an annoying bunch of angry crickets under the dash. Every time I've had enough and swear I'm going to pull the bastards out and fix it, - it stops then for 2 days, weeks, months. Very frustrating.

 

[Blue Streak]

Just another update. As I previously stated some type of binding is happening. I have been checking it more regularly since I am able to manually adjust mine, so my conclusion is if you have one that might be subject to this issue make your temp selection when everything is cool. Be it hot to cold or cold to hot. never attempt to adjust it when the heat setting has been set to max & blasting out heat, that is when the warpage happens. Let things cool down before trying to set at a lower temp. When time allows (and I find another mounting screw to replace the one I lost) I will reinstall the actuator & be more diligent on when I change temp. Just another experiment. Hope this helps someone.

 

[Dean]

If warpage has caused the "pin to jump out of the track" as described previously, Would it be possible to 3d print a newly designed arm/pin to address this issue? I'm pretty good with this kind of stuff.

It was warm today and I turned on the A/C for the first time this year and was greeted with a hot blast of air. I have a 2019 with about 18k miles. Out of warranty.

 

[airline tech]

If warpage has caused the "pin to jump out of the track" as described previously, Would it be possible to 3d print a newly designed arm/pin to address this issue? I'm pretty good with this kind of stuff.

It was warm today and I turned on the A/C for the first time this year and was greeted with a hot blast of air. I have a 2019 with about 18k miles. Out of warranty.

One could make the arm thicker or find something that would substitute the pin and make it longer.
The problem is (this arm) at this point is not available to purchase and the only way to get it is to buy the whole assembly.
It would be great if we could locate a PN for it and then we would have room to modify it without worry of damaging it (trying to get the pin out) to install a longer pin.

The main hurdle of 3D printing one is going to be the amount of warpage is going to vary for every case - the warpage amount will alter the dimension (measurement) of movement play on the end and how much the rod end is bent.
So, shimming out the bell crank to meet the guide pin is most likely the best option.
No matter what avenue you use, this is a band-aid fix for a deeper (not that expensive) if you DIY but is labor intensive fix.

The shaft warpage is the real issue, that creates movement binding, that binding on a plastic shaft with a DC Motor driving it causes it to bend and flex - this throws the guide pin off track, and it pops in and out of the track.
The band-aid fix is to close the gap just enough to keep it (in the track) - it does not address the real issue but at least helps it remain operational.

So yes, a 3D print of this either made thicker or with a longer pin is an option but may vary from truck to truck (how much variance- movement?) is occurring for the pin to pop out.
Will it be the same for all -IDK

Showing gouges in the bell crank from the guide pin popping out of the track

So, with using post # 555 @rrwhitman as a guide- when this is installed there is a small amount of play (movement) so it can move in and out - I think it's designed this way
but this design is for a perfect arm (rotation) track and when that track becomes deformed the designed play for this bell crank pushes all the way (outboard) creating a gap for the guide pin to pop out of its intended track.
By shimming out the bell crank (Lower side in this pic) it will draw it closer to the guide pin thus taking away the designed (play)

This would be where precision measurement is critical, shim too much and the bell crank is hitting the arm and or the guide pin is extended too far into the track and binding.

Showing bent arm either from jumping out of the track or extra tension created by the shaft warpage (Internally) and the actuator (force) caused it to bend.

Sponsored