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DeanoTS
13-10-2015, 04:26 PM
I noticed a bit of a smell coming from my air vents when I had the heater on in my KJ I bought a month ago, I thought I hope not but I pulled the carpet back this arvo and sure enough there's a slow leak coming from the heater core, does anyone have the step by step procedure on pulling the dash out to fix this problem, and any tips, cheers

peaandham
13-10-2015, 05:56 PM
There is a step by step that Madmagna wrote out, you'll have to search for it, or there are some photos in my build log.

DeanoTS
13-10-2015, 07:56 PM
There is a step by step that Madmagna wrote out, you'll have to search for it, or there are some photos in my build log.

I seen that post awhile ago, its for a car with no air bags, I need to know the procedure for a car with passenger and drivers air bag.

flyboy
14-10-2015, 09:08 AM
You can bypass coolant away from the heater core as a temp solution, probably not a bad idea seeing as we're coming into summer.

Might give you time to get the parts together and research what's involved.

I'm not sure about the airbags, perhaps PM Mal for instructions on any extra steps this involves.

ADM
14-10-2015, 10:15 AM
It's a prick of a job as it involves removing the dash including any passenger side airbag, steering wheel, centre console including shifter, fronts seats (easier access and work space with seats removed). Then un-doing the heater hoses from the outside then un-screwing & moving aside/removing the heater fan assembly so you can access the heater core.

90% of the time, the culprit is 2 x O rings that harden & crack, thereby causing the leak.
Given that it's a s**t of a job that you don't ever want to do again, it would be best to replace the O rings (get the genuine Mitubishi ones, they're like $1.50 for a pair), the heater core, the 2 rear heater hoses and also the 2 hard plastic gooseneck hose connectors that are screwed to the heater core (these do eventually crack and leak also).

If I can find find Madmagna's link for the basic procedure, I'll post it here.
As a precaution, make sure you disconnect the battery prior to removing airbags.

ADM
14-10-2015, 10:59 AM
This is the guide pretty much everyone including me, uses when replacing heater cores & associated components in 3rd gen magna/veradas.

Courtesy of MADMAGNA:

The heater is never turned off as such, it has a flap that redirects the air around the heater when not in use thus coolant flows all the time, this helps prevent corrosion and heating and cooling damage from expansion.

Ok, Here goes for a little essay of my own:

Am assuming no doggy bags

Disconnect battery
Remove front seats (makes more room to move)
Remove steering wheel
Remove column surround and combo switch (saves dropping column)
Remove "A" pillar moulds
Remove console
Remove gear selecter, (4 12mm bolts, clip and cable retainer)
Remove lower, middle and top facia plate (heater has 2 screws hidden behind the top, then unclips)
Remove lh panel under the glove box
Remove glove box and inner glove box sheild
Remove facia surround, instrument panel
Remove the thin metal plates down each side along the floor

Now for the fun part, bolts are all 10mm
2 bolts under the cluster, one at the top of the dash each side under the tweeter cover/blanks, one each lower corner, 1 each side lower where the console screws on. (think that is all of them )

Wiring, rhs, plug that goes into the the junction box and a grey plug that goes also to the dash harness (is a grey one). Middle, there is a plug with 4 pins (usually has a little cover on it) that has a 10mm bolt to hold it to the frame and an earth screwed into the lhs. The middle grey plug also comes out.

Now provided all is undone is good to lift out the dash

Next, the 2 metal uprights in the middle come out, on the RHS side you will need to carefully detatch the main wiring harness of the upright.

In the engine bay, remove the 2 heater hoses
Back inside is where the fun starts. You need to undo all the bolts for the heater box, air con box and fan box to allow you to pull the whole lot back about an inch or so. There are also some christmas tree clips holding the actual boxes together, get these out before you try and take out the heater box. Now with some fiddling the heater box will come out.

There is a single screw holding a white plastic retainer in, this come out and core slides out. You need a Torx bit (T30) for the screws, DO NOT OVER TIGHTEN THEM WHEN YOU PUT THEM BACK IN

Now to re assemble, reverse of above and take a look at all those photos you took while doing the dismantle

When you also re assemble, make sure that you also push the pipe back onto the condensor in the engine bay for the aircon drain

Think that is about it, it's off the top of my head as most of the time it's just something I do without thinking.

Madmagna
14-10-2015, 01:02 PM
Air bags, unplug them and remove them, no different really

ADM
14-10-2015, 02:36 PM
Add to that comment on airbags, there are 2 x 10mm head bolts that hold the passenger airbag in place, undo them while putting the other hand underneath the bottom of the glove compartment as the airbag module will slide out & potentially drop on the floor.
You unplug the airbag by flicking a plug cover then unplug the unit & remove. Probably best to keep the airbag module in a dry area & in an open plastic bag to prevent dust & dirt covering it.

With the driver's airbag, After removing the 2 Torx screws,when the horn cover is removed, you remove the horn spring bracket, 4 screws 2 either side under the horn pad. There is a yellow plug that is disconnected prior to removing the driver's steering wheel airbag from the cradle. Once that is done, the clock spring can be unplugged & the wheel is ready for removal.

As always, disconnect the battery prior to removing the airbags.
Also a tip, remove seats before disconnecting battery (assuming driver's seat is electric) & put auto shifter into N.

GoodOldJohno
14-10-2015, 04:37 PM
+1 for bypassing the heater, mines been bypassed for months now, winter was fun.

Madmagna
15-10-2015, 06:49 AM
Not sure on what car the above is for BUT on a Magna

Passenger side, remove glove box, remove lining trim, 2 x 10mm head bolts

Steering wheel, 2 x Torx 30 and they will be very tight, DONT damage them as if you do then you have to pretty much cut the steering wheel off to get it apart.

ADM
15-10-2015, 09:25 AM
Not sure on what car the above is for BUT on a Magna

Passenger side, remove glove box, remove lining trim, 2 x 10mm head bolts

Steering wheel, 2 x Torx 30 and they will be very tight, DONT damage them as if you do then you have to pretty much cut the steering wheel off to get it apart.

Looked back @ my photos and yes you are right Mal. I've ammended my post accordingly.
Thank you.

nate_115
15-10-2015, 02:05 PM
thanks for the guide guys, i have to do this soon, just need to build up the motivation to do so lol

DeanoTS
15-10-2015, 03:04 PM
+1 for bypassing the heater, mines been bypassed for months now, winter was fun.

I've just bypassed the heater, wont be needing it for about 5 months now, I might try and tackle taking the dash out over the Xmas break.

DeanoTS
15-10-2015, 04:55 PM
Courtesy of MADMAGNA: This is the guide pretty much everyone including me, uses when replacing heater cores & associated components in 3rd gen magna/veradas.


The heater is never turned off as such, it has a flap that redirects the air around the heater when not in use thus coolant flows all the time, this helps prevent corrosion and heating and cooling damage from expansion.

Ok, Here goes for a little essay of my own:

Am assuming no doggy bags

Disconnect battery
Remove front seats (makes more room to move)
Remove steering wheel
Remove column surround and combo switch (saves dropping column)
Remove "A" pillar moulds
Remove console
Remove gear selecter, (4 12mm bolts, clip and cable retainer)
Remove lower, middle and top facia plate (heater has 2 screws hidden behind the top, then unclips)
Remove lh panel under the glove box
Remove glove box and inner glove box sheild
Remove facia surround, instrument panel
Remove the thin metal plates down each side along the floor

Now for the fun part, bolts are all 10mm
2 bolts under the cluster, one at the top of the dash each side under the tweeter cover/blanks, one each lower corner, 1 each side lower where the console screws on. (think that is all of them )

Wiring, rhs, plug that goes into the the junction box and a grey plug that goes also to the dash harness (is a grey one). Middle, there is a plug with 4 pins (usually has a little cover on it) that has a 10mm bolt to hold it to the frame and an earth screwed into the lhs. The middle grey plug also comes out.

Now provided all is undone is good to lift out the dash

Next, the 2 metal uprights in the middle come out, on the RHS side you will need to carefully detatch the main wiring harness of the upright.

In the engine bay, remove the 2 heater hoses
Back inside is where the fun starts. You need to undo all the bolts for the heater box, air con box and fan box to allow you to pull the whole lot back about an inch or so. There are also some christmas tree clips holding the actual boxes together, get these out before you try and take out the heater box. Now with some fiddling the heater box will come out.

There is a single screw holding a white plastic retainer in, this come out and core slides out. You need a Torx bit (T30) for the screws, DO NOT OVER TIGHTEN THEM WHEN YOU PUT THEM BACK IN

Now to re assemble, reverse of above and take a look at all those photos you took while doing the dismantle

When you also re assemble, make sure that you also push the pipe back onto the condensor in the engine bay for the aircon drain

Think that is about it, it's off the top of my head as most of the time it's just something I do without thinking.

Thanks so much for re-posting this ADM, much appreciated

ADM
16-10-2015, 07:29 AM
No problems Deano ;-)

DeanoTS
22-01-2016, 06:34 PM
Thanks so much for re-posting this ADM, much appreciated

Hi all, just an update on the heater core in my KJ, I started to tackled the job two weeks ago and only finished yesterday was a pain but I got there, I didn't work on it everyday just when I felt like it. Thank's Mal for your step by step instructions, was a big help, plus I have a Haynes manual which helped with air bag removal. Somethings I would suggest if someone wants to do this for the first time is to take lots of photos (I didn't) label all the bolts, nuts and screws where they come from so you know exactly where they go back, I wrote on masking tape and stuck them to that. Taking the dash out its best if you have someone to help you as I dropped mine trying to reinstall it and broke a bit off it where it attaches to the centre console. I also replaced lots of the sealing foam as it just falls to bits with age, I just bought two rolls from Bunnings , called Econo-seal, was only $2.90 a roll. I didn't replace the heater core just the heater pipes and the seals. Cheers