'79 280zx Evaporator Removal / Expansion Valve Replacement
07-17-2014, 01:20 PM
#1
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Thread Starter
Join Date: Nov 2012
Posts: 6
'79 280zx Evaporator Removal / Expansion Valve Replacement
Hey guys,
Got to replacing the expansion valve on my Z (special thanks to borini63 for the parts!), and thought that I'd post up a pictorial for everyone else's reference.
Neither the dashboard nor the heater core need to be removed to pull it out, and it's not really that difficult of a job. I have no idea why the heater core would need to be removed like the FSM states.
Most of the pictures I took are getting everything back together, but I'll list them in reverse order - removal. Also, the beginning is pretty self explanatory, so no pics.
Please ignore the orange wires inside the glove compartment that I jerry rigged for my speaker.
Let's jump into it:
The easy stuff --
-Remove the center vent bezel, and the center vent (two screws at the top and pull forward)
-Remove the glove compartment
-Remove the kick panel and floor vent. The floor vent should slide out from under the center console easily with a slight twist.
-----
(Pictures in order)
#1 - Ventilation Ducts
-Inside the glove compartment, there are two ducts for the side vents. Reach back and pop them off of the vents at the side. Bend the large one forward outside the glove box and slide it off to the right (picture 1). Be careful, the upper smaller vent piece is connected to the defroster duct, which has had YEARS of sunlight. It will need to be bent against the inside of the dashboard to be disconnected.
-Remove the defroster duct. There is a screw (picture 2) towards the left side of the glove box. There are two more screws on top of the dashboard by the windshield, hidden under caps at the sides of the duct. I didn't bother with these, as my defrost duct shattered into a billion pieces near the upper opening. Once unscrewed, pull down on the accordion pipe inside the center vent hole, carefully disconnect the pipe at the top, and slide the defroster duct out of the glove box.
#2 - Blower Motor
-To remove the blower motor, disconnect the blue wiring harness in the center vent hole (picture 3).
-Inside the glove box, remove the two vacuum hoses running to the vent/recirculate actuator (picture 4). They're a lot easier to reconnect later than you'd think. Squiggle them through the guide tabs on the blower and evaporator boxes, and the wiring harness the other way.
-Looking from the bottom of the motor, and to the right of the warning module, you'll see two connectors hidden behind the dashboard frame (picture 5). Reach your hand from the top and disconnect the larger one. The smaller one to the right is slid into the blower box with a tab. Just push up on the bottom of the connector to slide it off. I believe you're supposed to press this tab down to get the top half disconnected. I ended up having to stick a flathead down into it to pop it open.
-Unscrew the blower box. There are two 10mm screws located against the firewall on the bottom side, and one on the top at the vent opening (picture 6). Work the motor down and out of the car.
#3 - Evaporator -- Half way there!
-Remove the warning module from the dashboard frame (picture 7, ignore my orange speaker wires). There are two 10mm screws on top, and one on the bottom. Once unscrewed, slide it towards the firewall, and let it hang there.
-Underneath the hood, disconnect the inlet/outlet pipes at the firewall (picture 8). This was the hardest part for me. I used a large pair of channel locks to grab the nut closest to the firewall, and I believe an 8" crescent wrench for the outer. These were REAL tight, and I ended up needing a buddy to help from the opposite side of the engine bay. Also, once the upper pipe is disconnected, it's easily and carefully bent to the side to make room for the lower. Cap these off on both ends to keep moisture out.
-Using a phillips head screwdriver, remove the screw in between the inlet and outlet pipes. Slide the black metal plate off the pipes, and pull the rubber grommet towards the engine, using the slits to pop it off.
-Back inside the car, climb down and pull the rubber drain hose for the evaporator box through the firewall (picture 9). While you're down there, unscrew the lower half of the evaporator, just to the right of this hose.
-Reach through the glove compartment, and unscrew the other two 10mm nuts at the top side of the box. These were hidden behind the defroster duct mount/screw.
-Slide the evaporator to the right, down and out!
#4 - Expansion Valve and Re-Foaming Ducts
-The expansion valve is pretty easy (picture 10). There is an 8mm nut on either side of the valve. I used a 17mm wrench for the expansion valve end, and my crescent wrench to disconnect the copper pipe. The valve will slide out of the casing with a little work, as it's a good tight fit.
-Get a putty knife and scrape off the old foam from around the duct holes on the blower motor, and the evaporator. I'm not sure if this is normal, but mine were covered in a black goo, so it was a really messy.
-I bought foam tape from Home Depot. It was only about $4 for 17ft. I wouldn't recommend it, as it didn't stick too well, but the material was perfect. Cut and place. Picture 10 is a good example of this.
------------
All set! As usual, getting everything back together is reverse order of removal, but it will be a lot faster. DON'T forget to re-mount the warning module BEFORE wiggling the blower motor back in.
Also, when putting the floor vent back in, make sure that you don't kink the vacuum hose running from the firewall to the vent selector. It runs right along the vent coming from the center console. This vacuum line is visible in picture 8, between the evap inlet/outlet and the engine.
Got to replacing the expansion valve on my Z (special thanks to borini63 for the parts!), and thought that I'd post up a pictorial for everyone else's reference.
Neither the dashboard nor the heater core need to be removed to pull it out, and it's not really that difficult of a job. I have no idea why the heater core would need to be removed like the FSM states.
Most of the pictures I took are getting everything back together, but I'll list them in reverse order - removal. Also, the beginning is pretty self explanatory, so no pics.
Please ignore the orange wires inside the glove compartment that I jerry rigged for my speaker.
Let's jump into it:
The easy stuff --
-Remove the center vent bezel, and the center vent (two screws at the top and pull forward)
-Remove the glove compartment
-Remove the kick panel and floor vent. The floor vent should slide out from under the center console easily with a slight twist.
-----
(Pictures in order)
#1 - Ventilation Ducts
-Inside the glove compartment, there are two ducts for the side vents. Reach back and pop them off of the vents at the side. Bend the large one forward outside the glove box and slide it off to the right (picture 1). Be careful, the upper smaller vent piece is connected to the defroster duct, which has had YEARS of sunlight. It will need to be bent against the inside of the dashboard to be disconnected.
-Remove the defroster duct. There is a screw (picture 2) towards the left side of the glove box. There are two more screws on top of the dashboard by the windshield, hidden under caps at the sides of the duct. I didn't bother with these, as my defrost duct shattered into a billion pieces near the upper opening. Once unscrewed, pull down on the accordion pipe inside the center vent hole, carefully disconnect the pipe at the top, and slide the defroster duct out of the glove box.
#2 - Blower Motor
-To remove the blower motor, disconnect the blue wiring harness in the center vent hole (picture 3).
-Inside the glove box, remove the two vacuum hoses running to the vent/recirculate actuator (picture 4). They're a lot easier to reconnect later than you'd think. Squiggle them through the guide tabs on the blower and evaporator boxes, and the wiring harness the other way.
-Looking from the bottom of the motor, and to the right of the warning module, you'll see two connectors hidden behind the dashboard frame (picture 5). Reach your hand from the top and disconnect the larger one. The smaller one to the right is slid into the blower box with a tab. Just push up on the bottom of the connector to slide it off. I believe you're supposed to press this tab down to get the top half disconnected. I ended up having to stick a flathead down into it to pop it open.
-Unscrew the blower box. There are two 10mm screws located against the firewall on the bottom side, and one on the top at the vent opening (picture 6). Work the motor down and out of the car.
#3 - Evaporator -- Half way there!
-Remove the warning module from the dashboard frame (picture 7, ignore my orange speaker wires). There are two 10mm screws on top, and one on the bottom. Once unscrewed, slide it towards the firewall, and let it hang there.
-Underneath the hood, disconnect the inlet/outlet pipes at the firewall (picture 8). This was the hardest part for me. I used a large pair of channel locks to grab the nut closest to the firewall, and I believe an 8" crescent wrench for the outer. These were REAL tight, and I ended up needing a buddy to help from the opposite side of the engine bay. Also, once the upper pipe is disconnected, it's easily and carefully bent to the side to make room for the lower. Cap these off on both ends to keep moisture out.
-Using a phillips head screwdriver, remove the screw in between the inlet and outlet pipes. Slide the black metal plate off the pipes, and pull the rubber grommet towards the engine, using the slits to pop it off.
-Back inside the car, climb down and pull the rubber drain hose for the evaporator box through the firewall (picture 9). While you're down there, unscrew the lower half of the evaporator, just to the right of this hose.
-Reach through the glove compartment, and unscrew the other two 10mm nuts at the top side of the box. These were hidden behind the defroster duct mount/screw.
-Slide the evaporator to the right, down and out!
#4 - Expansion Valve and Re-Foaming Ducts
-The expansion valve is pretty easy (picture 10). There is an 8mm nut on either side of the valve. I used a 17mm wrench for the expansion valve end, and my crescent wrench to disconnect the copper pipe. The valve will slide out of the casing with a little work, as it's a good tight fit.
-Get a putty knife and scrape off the old foam from around the duct holes on the blower motor, and the evaporator. I'm not sure if this is normal, but mine were covered in a black goo, so it was a really messy.
-I bought foam tape from Home Depot. It was only about $4 for 17ft. I wouldn't recommend it, as it didn't stick too well, but the material was perfect. Cut and place. Picture 10 is a good example of this.
------------
All set! As usual, getting everything back together is reverse order of removal, but it will be a lot faster. DON'T forget to re-mount the warning module BEFORE wiggling the blower motor back in.
Also, when putting the floor vent back in, make sure that you don't kink the vacuum hose running from the firewall to the vent selector. It runs right along the vent coming from the center console. This vacuum line is visible in picture 8, between the evap inlet/outlet and the engine.
07-17-2014, 05:07 PM
#2
Heater ducts
I am sure you noticed that each heater duct had a unique shape to the ends, triangle, or round or square, so getting everything to all match up is pretty easy, I had mine completely apart before I noticed and used it to my advantage. Good thing you didn't take the heater core out, that is teh hardest part to get back in since the controller is connected to it and all the vacuum lines, which are color coded and the FSM diagrams clearly shows where they go.
07-18-2014, 10:21 AM
#3
Registered User
Thread Starter
Join Date: Nov 2012
Posts: 6
Yeah man, VERY simple....besides the shattered defroster duct, hahah, but it should still function normally.
I just wanted to post this up, seeing as there are mixed opinions all over the place about it. Take out the dashboard, don't take out the dashboard, follow the FSM (which makes you do extra work).
I just wanted to post this up, seeing as there are mixed opinions all over the place about it. Take out the dashboard, don't take out the dashboard, follow the FSM (which makes you do extra work).
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