Hit-By-Thunder

My 2003 with the EATC was doing the defrost only thing. I tested for a broken blend door axle but I never had an issue with blowing cold then hot the cool etc. I have a vacuum pump, NO!!! not that kind and tested the headunit and the floor door vacuum motor worked. So test the line, it was ok telling me now it is the head unit. Well I did as one of the other threads/links suggested with replacing the 4 o-rings I saved the file and the user Devilsrighthand was bang on with his instructions. I am very happy that this worked out. No one has pictures but I did take some to show the tear down and the plunger with the rings that need replacing

photos and new thread are for search references

1) remove the 2 torks -T20 screws brass color
2) once apart, remove the red plug from the circuit board (red and black wires)
3) remove the vacuum port manifold
4) remove the 10 phillips screws and the silver bracket mine were coloored green
5) bend the tabs straight by the foam filters and gently pull the plunger out careful not to loose the spring and seat plunger inside

replace the o-rings, use silicone spray and 9/32 OD with 5/32 ID O-Rings and put back together, now enjoy the heat once again on the floor vent

whitetrucks

sweet info to be sure...

I nominate this posting as a sticky

jennkent5454

awesome thread, it needs to be a sticky,

where did you purchase the o rings from?

if you can, please add a link to the page of instructions you used.

jennkent5454

here is a link to write up about this--its very good!!!
http://www.mercurymarauder.net/forum...highlight=EATC


here is a link to the O Rings:
http://www.mcmaster.com/#

if the link for the orings doesnt work the part number is 9396K12

its a "007" oring
5/32 ID
9/32 OD

Hit-By-Thunder

I take no credit at all for the fix, I just found it and appilied it to me , it worked and then applied it for everyone here. I just thought with pictures, it helps that much more.

as for the O-Rings, us Canadian buyers can buy the o-Ring kit from princess auto for $5.99 and it has 225 plus orings. Also the kit contains 20 of the O-Rings needed for this repair.

Rob/HBT

MudHog

Bringing this back up.

I recently had an issue with only my MAX AC going to defrost. Did some research and found out about the orings. Replaced all (4) and now it works like a champ. Just yesterday (Sunday 4,11,2010) I have a buddy who's '03 was staying at defrost all the time. Sometimes during accel or decel it would blow throught he vents, but not often. Had him bring his truck over and we changed out his o-rings. His ring had hardened up so much they would break off. No elasticity what so ever. Changed his and now working like a champ.

Ford wants upwards of $800 to replace the whole control unit. They won't "rebuild" it.



The o-rings are a #007. 9/32" OD and 5/32" ID. You can buy them just about anywhere. I bought mine from Grainger and paid $2.39 for a pack of (100), yes 100 to the pack for $2.39.



If anyone would like to try this, send me a PM for my mailing address. I'll give it to you and you can then send me a self address stamped envelope. Once I get it in, I'll put (4) in the mail back to you, free of charge.

cowboyCadillac

the EATC is under the radio towards the floor right? I have an '01 SCrew

Tracka96

That post is very much appreciated. One question tho, all of these repairs seemed to apply to "defrost only" air, which is the default condition in case of vac failure. My2003 only blows thru the dash front vents, won't go to defrost unless I dis-connect the vac line to the controls. Then it does defrost only.
So do you think the o-ring fix would work for my problem? Tracka96

supernova1021

Bump for Tracka... I have the same problem.

Scottt

Thanks mucho for posting this fix, worked like charm!

My original o-rings weren't falling apart but simply flattened. New silicone o-rings topped with a dab of silicone spray did the trick.

Very nice to have air coming from dash vents again, like new