Imo000

I've removed the gauge pod to put a cover on it. My AC has not been working ever since I had the car. the PO told me that the "freeon" R12 has leaked out inside the car. Since I have the pod off I would like to know what it takes to remove the rest of the dashborad too.

Essentially I would like to remover the evaporater and have it inspected.

I think that with the dash out, it will be easier to install the Dastop cover too.

Any help is greatly appreciated.


Imre T.

onebad928s

you dont need to pull the dash off to do a good job on a dash overlay. I just removed the dash and it wasnt a real problem.You have to remove the center console first since your pod is out. Thers a few wires but mostly plugs.Dash itself has 4 screws (2 on top and 2 on bottom) and you need to drop the steering column that also bolts through a dash bracket.(3 small allan key screws).

Lou
83 928 5speed

JE928Sx4.

The dash itself is not that bad once the pod, center console and glove box are removed. It's only held in by 4 screws then. Two on the sides directly in front of the holes for the HVAC ducts. Then two more up and a little inward of those. With the doors open it just slides right out.

I have a couple of spare HVAC boxes and I took one apart for vacuum parts.....and to see how it worked LOL! I didn't use the evaporator. It looks perfect. Pretty sure it's for the 78 - 86.5 cars. I'll sell it to you for $40.00 plus shipping if you need it. The front of the HVAC box is held on with sheet metal clips. When you remove the expansion valve in the engine compartment and remove the front of the HVAC box, the evaporator pretty much slides out. It's probably a little tight removing parts on the box on the drivers side to pull it apart with the box in the car, but doable.

Regards,
JE

Thom1

Hi Imre,

The a/c has vacuum controlled actuators with rubber diaphragms that crack and leak. The a/c will not work without good vacuum/no leaks. I would replace all actuators while the dash is loose or out.

I would do a leak check on the refrigerant system to pinpoint the leaks before I pulled any components. It may save unnecessary work. Do clean the front of the evaporator.

Various versions of the following have been posted before, but I will hopefully save you some research by posting my latest update:

THOM’S A/C SERVICE ESSENTIALS:

RULES:
1. If you open the system: Replace the dryer. Vacuum the moisture out.
2. If you convert to R134A, flush the old oil & contaminants out. Change o-rings that are brittle and incompatible with POE oil used with R-134a. Oil o-rings before installation.
3. If o-rings are ever exposed, replace them with new ones.

RECOMMENDATIONS:
1. VACUUM GREMLINS ARE…STRANGER THAN FICTION! Fix them all before you try anything else.
2. With inexpensive R12 compatible refrigerants available, it may not be so good to convert to R134A. However, people have obtained very good results in 928s with R134A. See REFRIGERANTS below.
3. If you open the system, flush it too. By now it may have 2 or 3 times over the normal volume of oil plus contaminants.
4. Have refrigerant filled by a pro. You can blow out a hose or compressor by filling with cans, and/or without the proper gauges and/or methodology.
5. Replenish the pulley driven fan clutch fluid - get it from Toyota - Thickest part number version is 08816-10001
6. Clean the condenser – looks like a front radiator. While you’re at it, clean the radiator.
7. Expansion valve(s) may need to be changed – especially after compressor failure. (Sorry, but I do not know how to diagnose bad expansion valves. I don’t know if you get a big gain from this when the originals were still good. Many people really like to replace these to do it right. If they are bad, the system will never work right. There are different types specific to different refrigerants.)
8. UPDATE: An expert opinion states that old refrigerant hoses have been sealed by the old oil. Therefore they do not leak. Many people really like to replace the hoses per the old school leakage opinion. Some new compressors come with new hoses too.
9. Clean the front evaporator. This is accessed when the cockpit blower fan is removed. In the middle below windshield wipers… Leaves, bugs, hair, dirt, will accumulate here.
10. Install the 75C Radiator Fan Switch to engage the electric fan at lower temperatures.

FLUSH & FILL: To flush the system use professional equipment and/or: Disconnect hoses and remover dryer. Flush out the old components with a cleaning fluid, and proper equipment. (Compressed air puts moisture into the system, and can generate corrosive acid compounds. The shade tree mechanic really needs to vacuum the moisture out with a pump like the pros after flushing. Incompatible oils or contaminants can ruin your compressor. ) You should put oil into a new compressor, and turn it manually a few times before you turn on the A/C, and after flushing. Connect hoses, and vacuum out the system immediately after the flush. Do not expose the inlets of the new receiver/dryer and compressor to the atmosphere until you are ready to add oil and connect hoses. Link to instructions:
http://www.mastercool.com/manual/form12.pdf or go to mastercool home page by removing /manual/form12.pdf from the link above.

ORIFICE TUBE: Replacement of the orifice tube and dryer are required for warranties on American compressors. There is no orifice tube on a 928. The dryer filters contaminants.

REFRIGERANTS:
If you have R12, stick with it, or for less expensive refills – R12A, Freeze 12, Hot Shot or MP39 sound good as inexpensive, compatible refills. R134A conversion can reduce efficiency 8-12%. Links to alternative refrigerants:
http://www.duracool.com
http://www.btt.7p.com/AR/
http://www.freeze-12.com/
Links to discussions: https://rennlist.com/forums/showthre...threadid=81391
https://rennlist.com/forums/showthre...646#post679646


MORE INFORMATION OR PARTS: The Big 3 can provide parts. I have found excellent prices and service at 928 Specialists (828) 766-9280. See the griffiths.com site for parts and info. See the link below for in depth discussions by people from whom I have derived some of my recommendations:
http://forums.rennlist.com/forums/ul...&f=14&t=001183
More vacuum and electrical troubleshooting:
http://forums.rennlist.com/forums/ul...&f=14&t=002171
See Greg Nichol’s site for center console and instrument pod removal procedures, as well as more climate control tips: http://www.nichols.nu/tips.htm

VACUUM GREMLINS ARE…STRANGER THAN FICTION! There are 5 climate control actuators on an 86 model with flimsy rubber diaphragms to go bad. I have replaced 4 now. The remainder of this document addresses some of the vacuum actuators.

Check A/C vacuum at the black diagnostic tube going through the firewall at the brake booster. There is a 4 female point X connector there. (However, the previous test did not reveal a recirculation flap actuator leak for me. So, if climate controls do not operate properly, go to the next step.) If vacuum does not hold, check the colored tubes coming off of the back of the vacuum console behind the ash tray in the center console. Remove the left carpeted panel below the center console. Snip each colored vacuum tube, and check vacuum by pumping down the end that goes toward the actuator. Use an inch of rubber hose to slide over and seal the snipped ends of each vacuum hose.

ACTUATOR VACUUM HOSE COLORS, LOCATION OF ACTUATORS, HOW TO ACCESS INSTRUCTIONS
YELLOW - Footwell Flap, forward of center console behind climate control switchbox, pull back center console & remove right knee shelf & right carpeted cover below center console
GREEN - Defrost Flap, left footwell & forward of center console & forward of ignition switch, easier if you pull back center console & remove instrument pod – but not required. Remove left knee shelf & left carpeted cover
ORANGE - Center Outlet Comb Flap, lower right side of center heater vent, pull back center console & remove glove box & remove right knee shelf & right carpeted cover below center console
WHITE - Heater (hot water) Valve, beneath air filter box on right, remove air filter box
BLUE - Fresh Air/Recirculate/Flap, right footwell above recirculation grate, remove blower fan & right knee shelf & recirc. grate & fuse box wooden covers. Pull back fuse box.
BLACK – Source Hose no Actuator, X vacuum line at brake booster then goes to manifold behind stereo, open hood or remove left carpeted cover below center console
NOTE: Above sequence of colors is as located from right to left on center vacuum console

HEATER CONTROL VALVE: The A/C will never be cold with a defective heater control valve or vacuum leak at it’s adjoining actuator. The valve (under the air filter) will by default bleed hot water into the heater core unless all vacuum leaks on the dash side of the firewall (and engine compartment extension/heater control valve) are fixed. The valve can be defective even if vacuum is good. The valve can be installed 180degrees reversed. The white side of the valve goes toward the firewall side. (If you replace the valve, also replace the 3-inch long water hose connected to it.) See this link on Greg Nichol’s site for applicable vacuum testing procedures from Wally and company:
http://www.nichols.nu/tips.htm
RECIRCULATION FLAP ACTUATOR: On my car the vacuum test through the black test port line did not reveal this faulty actuator. You can feel the flap by putting your fingers through a 2-3 inch rectangular hole behind the glove box. You can easily push it up. If the flap does not rise up when the engine starts, with the A/C and Heater controls off, it probably has a leaking actuator. See Tony’s great pictorial write-up about the recirculation flap replacement. http://members.rennlist.com/v1uhoh/air.htm
Tony’s Center Comb and Heater Valve Lock-downs: (Note: A properly working a/c system requires none of these, or any other non-original modifications.)
http://members.rennlist.com/v1uhoh/summer.htm

Tony’s CENTER COMB ACTUATOR Replacement:
http://members.rennlist.com/v1uhoh/combflap.htm

John Pirtle’s vacuum actuator, center console, heater valve, etc. pictorial procedures:
http://members.rennlist.com/pirtle/svc.html

Imo000

Thanks for the info.

I'll let everyone know how it went, once I'm done with it. Probably in a week or less.

JE928Sx4.

Oh, I forgot. There are three small hex head bolts under the steering column to remove as well for the dash. Very easy to get to and remove. The the dash slides right out and you angle it around past the steering column.