How do you access the expansion valve on a 1987 Toyota pickup?

Answer 1

Replacing expansion valve on Toyota p.u.The expansion valve is located in and with the evaporator, inside the evaporator case. This case is a somewhat square, plastic enclosure located directly behind the glove box on this vehicle. Replacing the expansion valve requires removing the glovebox and the brace in front of it, disconnecting all wiring attached to the blower housing (located next to the evaporator case, disconnecting the hoses attached on the engine side of the firewall, removing several (10mm) bolts/screws that hold the evaporator case to the firewall and ultimately, removing the evaporator case from the vehicle. Once this is done, the case is held together by several Philips screws and one or two clips. Always 'backup' wrenches when removing a valve so as not to rip the liquid line or suction line off and always clean the mating area of the capillary tube and wrap it with new tacky tape. Don't foget to use new o-rings lubed lightly with refrigeration oil. It is important to remember to discharge the system BEFORE this procedure using approved recovery/recycling equipment or have this done by a qualified technician. It is also important to note that if you are replacing the valve because it is restricted or exhibiting intermittent closure (which are the only logical reasons to do so, [unless you have somehow determined that the valve itself is leaking {very rare for the actual valve of this type, likely the o-rings have corrosive build-up}]) that you will definitely want to remove the receiver drier (the system filter), flush the system using approved flush method(s) and chemicals and replace the drier with a new one. After all, if the valve stopped up or acting up, there must be trash in the system, and if you do not flush and replace the drier, you will be doing this again in the very near future! Remember not to open the drier or install it until you are ready to close the system as the drier contains dessicant material which will absorb moisture from the atmosphere and be ruined. Also, be sure to replace any (refrigeration) oil lost during this procedure, plus about 1.5 additional ounces. You must also be informed that, as a possible consequence of a restricted expansion valve where a system has been run for ANY length of time, there is always the possibility of a compressor problem (locking up) at some point in the future (from oil starvation). Before introducing refrigerant to the system, the system must be 'evacuated' (vacuumed to have air removed). Air in the system causes corrosive build-up and acids which lead to evaporator core and other aluminum part leaks. Check the label on the vehicle for the proper refrigerant charge. It is likely somewhere around 32 ounces (R12 type refrigerant. And the proper oil is 525 viscosity mineral). If the system has been (properly) converted to R134a, use Pag I, or low viscsity (46 weight) oil and about 10 ounces less than the R12 charge (IF it has been PROPERLY converted. It is illegal to mix refrigerants and ALL other refrigerants other than R12 and R134a are NOT approved by BOTH the EPA AND care manufacturers and some may containg flammable substance [illegal in all states]). Good luck and let us know how you make out.

SDI