I can't believe it - I bypassed my Heater Core!

[Ben850]

"Steam on your hand"?
Are you saying it was through the defrosting ducts?
A clear explanation of what actually happened will help.
Did all fluid leave the coolant system?
Did you stop driving the car when system failure was evident, if/so, how soon?
These and other clues will let on to which tools to bring. Or wrecker.

I am 20 minutes from Detroit. Where are you.

Edit: I am sorry, I now realize where you are.

[j-dawg]

i have a single-DIN radio and the pocket that goes underneath the head unit isn't installed. when the core blew, steam was coming out from under the radio and onto the shifter. hence, steam on my hand.

i was able to coast to a stopping point within about ten seconds, and the temp gauge never showed an overheat, though i'm not sure that's reliable if there's no coolant in the system. there is no coolant in the reservoir, and there is quite a lot in the cabin carpets. the engine bay and underneath the car were dry. the engine ran fine when i started it for a few seconds to move the car farther into the emergency pull-off.

my head gasket fears stem from the fact that i was driving antisocially when it happened. it must have been turning around 5000-6000rpm at the time. i can think of two possibilities - the high engine speed means a high water pump speed, which overwhelmed a weak heater core, OR an already-cracked head gasket was dumping combustion gases into the cooling system, and the pressure spike broke it. hence, i want to check compression once i get it back home.

i had noticed earlier that there was no record of heater core replacement. moral of the story: if you don't know its history, just replace it. it's pretty cheap and losing it is no fun.

[Ben850]

It sounds to be the correct diagnosis.

Back to your original limp home fix.
If you have strong fingers, you can actually pull the hoses from the firewall, or not.
Either way, you will need to squeeze the plastic yellow/white, clips on either side of the coupling and wiggle until there is a noticeable click and pull them straight out perpendicular to the firewall.

I had made a mistake my first time and cracked the junction in the firewall.

Get them both out inside the engine compartment. With a small screwdriver, or any delicate prying instrument, pry the plastic clips enough to remove them from the pipes. Remove O-rings and spacers if any had also followed.

I would say a foot or so, 5/8" heater hose with the appropriate clamps maneuvering in any way you can between the two tubes without crimping, would last as long as you like. (without heat)

Edit: As I see in the earlier thread photos, the plastic clips were left on the pipes. If it works, there it is.

[rspi]

I highly doubt you have done any damage to your motor. I would just bypass the core, top off the fluid, and drive on.

[j-dawg]

thanks! i'll walk over to pep boys and grab all that junk.

by the way, is it strictly necessary for me to make sure the hose doesn't crimp shut? the sense i get - and i'm not an expert here - is that there's no pump or device forcing flow through the heater core besides the natural flow, and that if i block the thing off entirely the flow can still run parallel to the core through that hard line on the back of the engine. shouldn't just preventing the release of fluid be sufficient?

[j-dawg]

and thanks for the video rspi! as always, your youtube channel was the first place i went.

[erikv11]

That is correct, a crimp would be no problem at all. The only requirement on the bypass is that you stop the leaking.

[j-dawg]

and stop the leaking i did! the hardest part was getting those yellow clips out of the firewall coupling. i mighta broke something in there

nonetheless, i took it easy on the way back. i always find it nerve-racking to drive even knowing that the light is gonna come on when the thermostat opens up. i'm gonna drive it pretty aggressively these next few days and if it holds together i'll head out to detroit on wednesday.

thanks again for the help!