LJ78 1990 Prado Heater core leaking (1 Viewer)

[EMTPrescue]

I am hoping somebody out there in Cruisier Land has experienced the challenge associated with the removal of the heater core from their vehicle. My SUV has developed a leak in the heater core dripping small amounts of coolant on the floor mats and fogging up all the windows when the sun goes behind a cloud.

I spent about three hours disassembling a sizeable amount of the dash and with my now being able to visualize the heater core housing, it is pretty obvious that Mr. Toyota never planned for the core to be removed once the truck was built. Based on what I can see, I will have to remove the entire dash board to get the core out.

Of course Cousin Murphy has come to visit as well because it has got cold up here in the Great White North. The outside temperatures are about -10F or -25C so I can only work on it for about 10 minutes before my finger tips freeze and become useless.

Hope one of you guys can help me with some suggestions.

I have a newly flushed coolant system, new antifreeze and a new radiator so I am very reluctant to pour a leak sealing product into it like Bars Leaks. I know the product can seal the leak but it is non discretionary and all of those types of products are famous for the undesirably plugging up of other things like cooling journals and rad tubes.

 

[pradoblivious]

I know I've read a thread on here with pics from someone who removed his heater core and had it patched, but I can't find it. If memory serves he began believing he would need to strip down the entire dash before he realized all you needed to do was remove a few key components like the steering wheel, and then there was a series of bolts along the top of the dash which, once removed allowed the entire dash to slide down and out, providing access to the core. I'll see if I can find it

 

[pradoblivious]

I'm still looking, but went out to look at my own truck, and if I'm remembering correctly, this was the line of bolts you want...

 

[pradoblivious]

here's a thread on it; seems like maybe I'm wrong.

Heater water lines

My 93 LJ78 has a significant leak on cab side of the heater return line. My shop manual is not helping and MegaZip has fairly decent images but what I can’t tell from these is are the two lines from heater core hard lines and do they extend through the firewall or are there two shorter lines...

forum.ih8mud.com

 

[coldtaco]

you will have to totally remove or at least move the metal dash out of the way. you have to disconnect the heater lines in the engine compartment to pull the heater box out in the cab, and disconnect the wire that goes to the heater valve in the engine compartment. disconnect all the controls (wires) from the different places they go to, remove the lower center dash. unfortunately it will be a pain to do but it is pretty straight forward. have you installed a electric heater in the cab so you can work in the cold?

 

[Honger]

Mine had no heater core... and so I had to retrofit my HVAC system and install one.

Yeah, you're going to have to go pretty much all the way in on the dash.

 

[Honger]

 

[Honger]

On the up side you'll have an opportunity to clean a lot of things up.

Knowing how bad this was going to be I had my used heater core pressure tested and the o-rings replaced on it's swivels.

 

[Honger]

Helpful thread.