Heater Core, removal and flush?

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FJBen

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Since I'm rebuilding this 13BT, the last piece of the cooling system to deal with is the heater core.

I've had the radiator rebuilt, new water pump, new hoses. I was planning on flushing the heater core, but now I'm leaning towards removal, testing/repair if need be. There are no signs of leaking, but I do know the cooling was in poor condition. As I'm putting a great deal of time and money into this engine, I'd rather not have crud from the heater core ruin anything.

Do you have to remove the dash on the BJ74 to get to the heater core? I'm not seeming to find much mentioned about this in the manual.
 
You have to go deep to get it out and back in. All the way to the main wiring harness which is against the firewall. Pictures are in my PZJ70 thread. Big job on a 70 but relatively easy. You could clean any funk out of the dash while you are at it, no better time to do that! Also no better time to clean up any wiring that might need it in the dash. There was a tiny bit of surface rust forming here and there on the main metal dash piece in the PZJ70 so I took the opportunity to clean that up and paint it as well, looks like new now. Local auto paint supply shop matched the dash color very closely and put it in rattle cans for me.

Cheers
 
G'Day Fella's,

LazLfarm, about 1 or 2 years ago, I wanted/needed to do the same as yourself (on 1990, BJ73).
I removed the dash, etc, and then the heater coil (see attached image).
I didn't know if the coil was leaking, or if it was the flexible joints, that connect to the coil?
The coil was fine, so to completely rectify this, I soft soldered the heater coil Supply and Return pipes, to the two brass pipes (you can see them in the image), that penetrate the firewall.
To do this, I disconected and removed all parts, and soldered them together, in the Funshop, then reinstalled them.

Also and at the same time, whilst the dash had been removed, I replaced the squeaking speedo cable.

Hope that helps

D'oh!
Homer

DSCN1991.webp
 
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I reversed flushed the heater matrix on my FJ73. I got a lump of black sludge then clean water and it was never a problem again. Cant say Ive seen too many rust out
 
I figure this wasn't going to be a particularly fun job. I pulled the glovebox this morning and yeah, it doesn't look fun at all.


I reversed flushed the heater matrix on my FJ73. I got a lump of black sludge then clean water and it was never a problem again. Cant say Ive seen too many rust out


Thats some good info there. I can't say as I have heard of a lot of these failing. I may try and flush it first to see if there are any leaks and what nastiness comes out. I can't say as I really want to pull it out, but...
 
Depends where the truck came from and who owned it.

Did they put water in the system and no coolant? That will make a core fail over the years.


Cheers
 
Depends where the truck came from and who owned it.

Did they put water in the system and no coolant? That will make a core fail over the years.


Cheers


Came from australia and overall it's in pretty solid shape compared to a lot that I see online. As for who owned it before my friend for the last 4 years, no idea other than someone down the line built it and took care of it.

It had coolant in it when I started the teardown, albeit nasty coolant. I assume a lot of that reason was because of the HG failure.

I will start with the flush and see what nastiness comes out of the core.
 
LazyLfarm, my best advice, is to start and finish this job, with the least amount of time between this.
That way, hopefully you will remember what goes wherem etc.

Good lucj with this

Avagreatweekendeh!
Homer
 
LazyLfarm, my best advice, is to start and finish this job, with the least amount of time between this.
That way, hopefully you will remember what goes wherem etc.

Good lucj with this

Avagreatweekendeh!
Homer


Great advice. I'm already worried about putting the 13BT back in thinking, I hope I remember where everything goes.
 
Great advice. I'm already worried about putting the 13BT back in thinking, I hope I remember where everything goes.


Exploded parts diagrams and FSM.

:)


Cheers
 

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