the tabs actually work forever, at least until the system is flushed, requiring more tabs.

its not the best repair, but its also 999 bucks cheaper than 1000. And it works fantastic.

 

I know what your going through, but I must say It's probbaly the o-rings and not the H-core. I've attached instructions in this message that I used to fix my o-rings. I got these from a search online and this person did a great job with the instructions. I didn't remove anything I didn't have to that's for sure..... Embarassed to admint I was impatient and just removed my A/C refrigerant improperly. System was recharged, held a vaccuum and works great to date. You can also search on the forum "heater core" and you'll see my thread of my H/C O-ring replacement. Well hope this helps...............

1. Disconnect the negative side of the battery. You'll be working around the passenger side air bag and you don't want that to go off!!!

2. Order 2 (TWO) O-Ring gaskets, Mitsubishi Part Number MR927776, they were $2.65 each on-line + $9 shipping. For what it's worth, it appears that the newer ones are a different design. The original (from my 2001 D) has a ridge around the outer perimeter on one side only (though it could have been flattenend out from being installed). The new ones have a ridge around both sides, so I assume they seal better. HOWEVER, I just noticed another post that indicated that the TSB listed the MR925655 part. (Hope I didn't put in the wrong gasket!!!)

3. Get the freon removed from the car. (I have a friend that removed and will recharge the system for me).

4. Make sure the engine is cool. Drain the anti-freeze. You don't need to jack up the car. Put a pan under the front right of the car and reach down between the engine and radiator and turn the white plastic valve a few turns, and let it drain straight down, be patient (Don't remove the valve). Once the fluid is drained, tighten the valve again. You'll get about 1 gallon of anti-freeze mix.

5. Remove ONLY one of the two heater hoses, closest to the passenger side, on the firewall. The other heater hose doesn't have to come off. I used a pointed nose pliers to squeeze the clamp, and pulled it back over the hose. You may have to turn the clamp to get good access. Put a towel below the hose to catch the coolant that will leak out and twist and then pull the hose off.

6. Remove the 10mm bolt from the smaller AC line at the firewall, behind the engine, as well as the bolt that helps to attach the same line to the firewall (for extra play when sealing the line).

7. Remove the 12mm nut from the larger AC line at the firewall. I found that a long extension and a flex

8. Seal the ends of the AC lines (I used plastic bags and rubber bands) to keep any debre out.

9. Remove the rubber hose with the 90 degree bend located slightly to the right of the AC lines. This is the AC condensation drain hose.

NOTE: When working under the dash, it helps to have a knee pad or something to kneel on.

10. Moving inside the car, Remove the Under Cover assembly below the glove box. There are 3 plastic fasteners that pull straight out.

11. Remove the Glove Box (2 Phillips screws) and then the glove box frame (4 Phillips screws). Use pointed nose pliers to remove the tabs that hold the wire to the top of the frame, and use a flat blade screwdriver to remove the connector on the top of the glove box frame. This connector goes to the passenger side air bag. Handle with care!

12. Remove the metal frame bracket from under the glove box, being careful not to damage the wire to the light switch. Use a fine tipped screwdriver to pry the small connector catch (wrapped in foam to keep from rattling) so that connector pulls apart easily.

13. Remove the left side heavy "Z" brackets from the round tubular frame from above the evaporator unit. The one on the right side doesn't have to come off, it won't be in the way.

14. Remove the 2 12mm bolts at the top of the AC Evaporator and the 12mm nut at the bottom. Also disconnect the two connectors that are on the side of the evaporator.

NOTE: You do not need to remove clips that hold the two halves of the evaporator housing, nor the black connector block on the right side, nor the black plastic piece on the left side of the box. NOTE: The fan assembly on the right side does NOT need to be removed.

15. Pull the carpet back to make some extra room and so that when some of the AC oil leaks out, it won't get on the carpet.

16. Now comes the tough part, getting the evaporator housing out. (i.e.: 10 lb evaporator, 5 lb opening!!). Pull it forward some, then bend the front down (toward the floor) and pull it around. Takes a bit of playing, but it will come out. There will be a bit of AC oil that drains out on the floor, but with the carpet pulled back, just wipe it off the underlayment floor surface. Shouldn’t be more than about 1/4 oz.

NOTE: After re-installing the evaporator, I think that it might be wise to bend the metal bracket that holds the left side of the glove box (attached to the center console inside supports) back and out of the way. This should not only help in getting the box out, but also back in (which is WORSE than trying to get it out!)

17. Looking up to the left, you'll see the hoses that are connected to the heater core. You won't be able to remove the heater core, but you will be able to remove the 4 screws (#20 torx head) from each of the two hose blocks. BUT FIRST put 2 or 3 towels on the floor (stuff them around the metal brackets) to keep the coolant from draining into the floor mats.

18. You will be able to remove the upper black plastic hose end (twist it upward), but the other metal pipe is fairly firmlly entrenched. There is enough room to remove the plastic bracket between the hose and the heater core though, along with the o-ring.

19. Spend some time cleaning up the anti-freeze from the area to help get rid of the smell, or it may be around for a long time. I did note that they put a piece of plastic on the top of the ECU (under the foot distributor duct) so reach in with a paper towel and wipe it off. There was some discussion on the board about covering it completely, but my concern (being an electronics engineer) that if you seal it too tight, it won't be able to cool as well as it needs to. Anyway, I used a squirt bottle to put some water around the heater core, but it doesn't drain out. Soak up the water with paper towels. (Anyone have a better idea on how to clean up?)

NOTE: There is a plastic bezel that goes between the lower hose connection on the heater core, which surrounds the lower o-ring. There are some square prongs that stick out. These prongs go toward the heater core. Look at the upper plastic hose connection, it's essentially the same, but the piece with the prongs is not removable.

20. I would suggest that when you are putting the heater core screws back in, with the new gaskets, that you add a touch of a medium strength lock-tite to the screws so there's less chance that they will work their way out again. Remember that the screws go into a plate of aluminum, about 1/8 inch thick.

DON'T OVER TIGHTEN!

21. Be careful when putting the evaporator back in, not to damage the fitting surface. When re-installing the AC lines, don't over tighten. They are aluminum fittings. Handle with care.

22. Getting the evaporator box back in is worse than trying to get it out. You're on your own here. I ended up breaking the black plastic bracket behind the left glove box support (so I bent the metal bracket back, as mentioned above). I just glued it back into place with a good epoxy. No one will ever see it.

Reassembly is the reverse. Use new Anti-Freeze to replace what you've drained.


And yes, I broke the same plastic piece. -Ryan

 

Thank you Guys,
I've replaced the O-rings and there is no leaks now but I have an another problem . I've brought my D to the local mechanic to fil the AC and now the air is not as cold as it use to be . The mechanic has put 1.8 lb of refrigerant but I'm sure that wher he did get it out he told me that it was 2.1 or 2.2 lb ( I can not remmember exactly because it was two weeks ago , I should have written it down) . Anyway he thinks that I did not connecte the valve door that is mixing the cold and hot air from the heater and the evaporator . I have checked it and it is working just fine . I think he did not put enough refrigerant and would like to know if there is a specification for Diamante and how much is it .Any advice appreciated . Zonk.

 

the refridgerant quantity is located on a sticker under the hood.

1.5 pounds is about correct.
so hes possibly correct. are you looking at the correct blend door? The temp mixing door is located on the passenger side of the car, to the immediate left of the glove box.

 

Curious now. I had my heater core swapped last year and now I get very little cold air through any of the vents. Fan sounds plenty powerful. Could the dealer have screwed up something when they did the work on my 2002 D? Figures that they are now out of business, but I'm sweating like a pig! Thanks...

 

The lack of air coming from your upper vents in the Diamante is a very simple fix.

On the driver side of the "transmission hump", you will see a black servo that moves a plastic lever.

Lay on your back with your head under the steering wheel and activate the climate control to the defrost setting - you will see it move.

There is a detent in the last position that the servo actually fits into. This pops out and thus - no air to the upper vents.

Just pop it back in and it you want, secure it with a clip or tape.

Did mine in 2 seconds (after 1 hour diagnostic inspection) and it hasn't popped out since.