heater core diagram STAT

[tomatofiasco]

STAT! my heater core is leaking randomly, especially past 3krpm, and there is lots of rust sludge on the radiator cap.

do i really have to take the ENTIRE dashboard off? i havent got a shop manual and having done it once, its not something i have any desire to repeat. still, a problem is a problem and coolant on foot is a do not want, so any scans or diagrams or pointers or warnings would be a huge help pronto.

plz plz plz

[lostforawhile]

STAT! my heater core is leaking randomly, especially past 3krpm, and there is lots of rust sludge on the radiator cap.

do i really have to take the ENTIRE dashboard off? i havent got a shop manual and having done it once, its not something i have any desire to repeat. still, a problem is a problem and coolant on foot is a do not want, so any scans or diagrams or pointers or warnings would be a huge help pronto.

plz plz plz

you have to remove the dash, the two connections to the heater core stick through the firewall, while you are at it fix all the little hoses going to the heat control valve,it's in the engine compartment. no point in doing them later,also if you have sludge stuff in your coolant,you need to go ahead and flush it before you put in the new one,or it will get into the new core.

[tomatofiasco]

thanks lost!

damn, what a pain. well, as you might be aware from the news of unprecedented firestorms, its high summer here and will be for a few more months. so i drained the coolant, took the top hose off completely, and moved the bottom hose to where the top one was connected at the engine end. it kinked a bit making the 270 degree turn required but it clamped up okay, so i hope i have successfully eliminated the heater core from the system without causing some new and terrible problem beyond my imagination. i'll put the removed top hose across the two brass heater supply tubes, partly so i dont lose it and partly to stop the exchange of grubby crap between the heater and engine bay, while i investigate replacement options.

i'll put the coolant back in tomorrow as its fairly clear and green still [and i'm out of additive] and see if it drives.
unless anyone can think of a reason not to...?

[79cord]

Are you sure your problem isn't just you heater tap/valve to the right of the heater core in the cabin?
-By the Prelude of '79 Honda had already relocated it into the engine bay.
Shouldn't be that hard to access.

[tomatofiasco]

79cord, i am fairly sure yeah. while i havent actually seen exactly where the water was squirting out of, the evidence was:

water dribbling and dripping intermittently from the heater box [from the clips that hold it together in the middle]

a squirting sound like air locks in a hose, that sort of swirling bubble noise

mainly happened when revved beyond ultra economy mode

drips were lukewarm or cool

inlet tubes under the dash were dry [and hot-ish]

lots of rust sludge floating in the radiator top tank

all that made me think it was likely to be the heater core, which had developed a small [but growing] rust-hole in the channels somewhere, and was exchanging air for water, which it dripped or sprayed onto the heater box interior, which pooled at the bottom, dissipating its heat to the plastic, and then seeped out the central seam, onto my floor and indirectly onto my foot.



anyway, i tried out the new, simplificated summer sports configuration, and it seems fine. and NO SQUIRTING NOISES!

of course now its cold again and the demister doesnt work so i will have to activate my shammy instead