Heater Core Replacement... I need some Help!!

[Ryan King]

I am going to be disassembling my Evaporator box this weekend to remove my heater core and do a refurbishment on the box itself, as seen at this link -

http://dmctalk.org/showthread.php?5860-Heater-and-Evaporator-Replacement-with-Heater-Box-Restore

But According to the work shop manual the AC System has to be De-Pressurized for removal of the Heater Core? Is this true? I really need some advice on this. My heater core is currently bypassed, so my plan was to disassemble everything this weekend to prep everything for the arrival of the new core.

HELP!!!

-Ryan

[Ryan King]

According to this thread, you can remove the heater core without removing the evaporator?

http://dmctalk.org/showthread.php?620-heater-core-evaporator-replacement-tips/page2&highlight=heater+core

I would like to pull the whole box out to re-seal everything tight and replace all the foam bits, which I have already purchased.

[Farrar]

In my experience, there are some screws on the back of the heater core/evaporator box which are impossible to get to without removing the entire thing as an assembly. Some people may have had luck disassembling the unit in situ, but I am not one of them. I certainly can't see how you could re-assemble the box in the car; you'd likely have to leave out some of the screws on the back.

Sorry if that's not very helpful; it's just what I've experienced on my car only.

[Ryan King]

In my experience, there are some screws on the back of the heater core/evaporator box which are impossible to get to without removing the entire thing as an assembly. Some people may have had luck disassembling the unit in situ, but I am not one of them. I certainly can't see how you could re-assemble the box in the car; you'd likely have to leave out some of the screws on the back.

Sorry if that's not very helpful; it's just what I've experienced on my car only.

But in theory, I could use a ribbon sealer to seal up the back end of the box without having to reinstall the screws. Ill just have to see how patient and nimble I can be with getting into the back of the box.

[DMC5180]

Ryan,

Whether you can or can't successfully split the unit in the car is not the point. The risk of doing irreparable damage too NLA parts is substantially high. Ask me how I know. I regretted trying the short cut from the instant I heard the SNAP sound. So I highly recommend you follow the manual. If that means emptying the A/C do it. Btw are you running R-12 or R-134a? With 134 you can go to a local shop and have them empty the system so you can work on it at home. They will record how much refrigerant was removed (credit amount). Then when it's time to refill it you only pay for the amount over(if Any) the recommended amount plus shop time, figure 30 mins total for pull down and hold (15 min) then fill (5 Min or less) plus incidentals assuming no leaks are detected. Finding shops that will deal with R12 is increasingly difficult.

[ssdelorean]

I replace my heater core without disconnecting any AC lines. My biggest problem was getting the box out from under the dash. Was able to play some mean tetris to make it work. If you have the means to evacuate the lines, store the R12 & re-install, that would make it much easier to get the box out of the dash with the AC items disconnected.

23647

[andy blackmon]

A year or two back I replaced my heater core. If I can do it any one can. I did not do anything to the AC unit. However it did take me around 7 hours of tearing out the duct work and replacing it . Be sure to mark what you take out in the order your remove it this will make putting back so much easier
Andy B 03513

[kings1527]

So I'm guessing everyone is taking the box apart inside the car without removing it? That's the only way I can think of without taking the box out of the car and having to discharging the refrigerant and disconnecting the evaporator so everything will come out.

[Ryan King]

I was able to split the box in two and pull it out. The work was really easy. They only real hard part was getting the box out of the dash. Getting it back in is going to be a toughy.