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Hi guys.

Anyone pulled the evaporator box from behind the glovebox on an NB. I have found in addition to lazy eye balls, my NB also has a broken clamp from the right side of the box, which means most of my AC is escaping before finding it's way to the vents. In the process of finding the clamps, but will need to get the box out to get to the clamps when I get them.

Also, if anyone has done this sort of job, is there any other bits I should be cleaning up/replacing while I have this out?

Regards
Peter

Be sure you really want to pull out the evap. as this means dumping your gas charge $$$ . Perhaps remove loosen the nuts holding the box in place [ don't forget the one on top ] so you get wriggle room , the suction / discharge lines exiting the firewall are in rubber grommets so have limited movement . Now you may be able to remove the plastic ducting on the out side of the evap. The clamps can be repositioned and if your lucky reinsert duct and clamp up .

One of my customers is the local car AC guy, so I know I will get looked after on the gas if I go the full pull out. The only bit that is concerning me is dealing with the pipes through the bulkhead. Seems this is the bit everything I have read suggests is the hardest bit. I will readily admit I am a complete novice at messing around with cars, but something about this car is telling me to give everything a shot myself. Did the shifter bushing without any hassles, and maybe that is making me a little too confident in my own abilities.

I think I may have to resort to some duct tape though. Finding an NB in a wreckers in Adelaide to salvage parts from is proving difficult.

Peter

The tubes through the firewall are a piece of cake , take two spanners to them , and they will undo quite easily as they use an o ring to seal so should never be over tightened . Replace all o rings ! Very important seal all tubes and I mean seal , as the a/c system will suck air/ moisture in which is not good . When you get your evap. box out , as an extra job split it open , take a lot pictures of how it looks especially the small diameter capillary that is pushed into the fins . Now hose out the lint/ leaf matter and clean between the fins carefully . If you wish you can use a
'specific" acid for alum. on this evap. and it will come up quite well , rinse off all acid . Put you a/c back together as soon as possible , a new drier is very important , evacuate system and regas do this in days not months . Now you will have good clean cold air with no " smell "

Peter , are you sure the clamp is broken ?? these from memory are a two piece clamp and secondly there is no stress or fatigue on these clamps so no reason to be broken . give me a call if in doubt . 0413208750 Max

The clamp on the left (passenger) side of the evaporator box is a two-piece clamp that forms a square to seal with the blower unit.

The clamp on the right (centre of car) side is a single-piece clamp that forms a triangle to seal with the heater unit.

After time the foam lining of the clamps deteriorates and the clamps come loose. Then you have no seal and a terrible rattle from behind the dash.

In an NA, it is possible to remove both clamps without removing the evaporator box. I hope this could be the same for an NB.

Yep , your spot on correct . I glued some new foam onto the clamps , actually renewed all the foam in the heater box / flaps etc which after 25 yrs had turned to a dark brown semi dust . Sourced a similar foam from a foam specialist and contacted glued it on .

Smacca wrote:The clamp on the left (passenger) side of the evaporator box is a two-piece clamp that forms a square to seal with the blower unit.

The clamp on the right (centre of car) side is a single-piece clamp that forms a triangle to seal with the heater unit.

After time the foam lining of the clamps deteriorates and the clamps come loose. Then you have no seal and a terrible rattle from behind the dash.

In an NA, it is possible to remove both clamps without removing the evaporator box. I hope this could be the same for an NB.

Must be the triangle one then. Looking at the parts diagram for the NB that is in the Technicals sub, I can't seem to see this part, which is why I was assuming it to be the square one. Mine is not just loose from the foam, it seems to be cracked right through he bracket, about the right hand extreme of the photo here.

Perhaps it can be repaired with a small scab patch around 30mm long x 20mm wide x 1 or 1.5 thick with a total of 4 3mm pop rivets [ heads inside ]