Replacing the E30 Heater Core and Valve

[e30topdown]

Just did this. Replaced everything with new - heater core, valve, and pipes. Yes the new version of the heater core is bigger, but loosen the nut on top and it swivels. A loose flyer in the bottom of the box said to finger tighten the nut on top of valve when in its final position. That's to work around the relay, etc.
The other thing I found is its much better to put the o-rings in place over the male part of the pipe, instead of fitting into the core side first. I pinched one o-ring when I first put it together and had a leak. The second time around I put the o-rings on the pipe side and put it together without any leaks. I didn't see anyone suggest this after reading through all the posts.
OP, thanks for a great write-up. Really helped me get this done rather easily. And I am truly thankful that I have an A/C car, because it looks like a bitch job if you don't!

[E30FreaK89]

i just installed the new version of the heater valve yesterday along with a new heater core and since its bigger you need to move a relay next to it. It way bigger than the original.

[d_elson0]

I began looking into my heating issues lately. Is there fuse that may need changing for the heater control valve to receive power to open (fuse 20 I think)? Mine seems to be in the closed position (when plugged in or not. I have removed the valve and hooked it up to see if I can blow air through w/ no luck).

Just trying to diagnose before spending more on a new valve (shows no wear or leaking). I have bought a new core since I'm in there, but haven't read about many valves being stuck in the closed position w/ or w/o power.
Thanks for advice.

Also, which line does that inline thermostat go into? The line coming from the head or the block.

[///M42 sport]

bought a new heater core valve

So shiny :)


comparison is alot beefier. Hope it lasts as long as original!

[///M42 sport]

just looked at mine today and looks like my heater core valved is leaking....DAMN

[///M42 sport]

so if the windows fog inside if I use the heat, should I assume its the heater core?

[blazinxpk]

Color doesnt matter. Ive pulled different looking valves from pnp before.

My heater didn't work, applied voltage to the valve it didn't open, went to pnp bought valve, heater worked after replacement, total cost $14. didn't even replace the o-rings.

[xcx4x]

Update:

I pulled a heater valve off a parts car from a member here.

However...its a different color (black instead of green/aqua) which leads me to believe it may not be the correct one...

Here is a picture comparing them:



1. Does anyone know if they are interchangeable?

[xcx4x]

my friend and i were talking about the valve. we were very interested in how it failed like that. coworker mentioned maybe something was in the way of the valve, so when the valve closed it hit the debris and pushed itself out.

anyways, in the meantime, my friend wanted to try and fix the valve assuming the valve still works. we are going to pull out the collar pins that hold the solenoid valve to the hose. then we're going to make a rubber gasket of some sort and seal it up. finally drill/tap new holes and fasten it the same way.

we'll take some pics and keep yall updated.

[///M42 sport]

goddman why does that valve have to be so pricey

[xcx4x]

That parting line is typically where the valve will fail.

As for the tiny bolts, my only advice is to not lose their nuts. You can keep them captive with a tiny amount of poster putty or similar if you are having a problem with them.

+1.

I just ran some water through the valve and exactly where you specified spewed a leak.

=(((((((((((((((((((((((

i wonder if this was because i tugged it a bit as i was getting the heater core out..but all the residue implies it failed awhile ago..

So...anyone have a valve for sale? =)

edit: none in for sale. anyone know a budget valve for sale?
edit2: anyone know a good pick n pull around long beach area +anywhere nearby?

[cunninglinguist]

That parting line is typically where the valve will fail.

As for the tiny bolts, my only advice is to not lose their nuts. You can keep them captive with a tiny amount of poster putty or similar if you are having a problem with them.

[xcx4x]

EDIT2: Valve leaking. Need a new valve.

Quick background: Got car. Found repair documents. One said A/C not working, Heater core faulty. I got a new (used) heater core. Now I'm replacing heater core.

OOOOOOOOOOOOK

so update, with a coupla questions. some practical, some theoretical, some general.
I got the heater core out. I think i had the hardest trouble with the three 8mm screws (hexagonal tops) that attach the heater core to the pipes. I'm talking about these ones:




because of how hard they are to reach.
Q1: Anyone have any tips for when I reinstall?

After I pulled the heater core I realized what it was. Just a piece of metal. Which makes me wonder...
Q2: How does a heater core fail? Leak? Clog?
Q2.1: How can I check if its bad or not? can I fill it with liquid and coat outside with soapy water and check for leaks? I'm guessing this wont work because i'd need some pressure.


This leads to me to think that maybe it wasnt the heater core that failed. Maybe it was my valve? Here is a picture of it:



I guess the picture is kinda biased because of that white stuff on the edge of it.

Q3: But if a valve were to fail, is this the way it would fail? Or perhaps this is just random residue or residue from when the O-rings failed awhile ago.

EDIT: I will try plugging it in and turning the temperature knob and "listen" for a click or any movement of the valve.


So currently, all O-rings will be replaced, and old heater core is out. I am reluctant to put in new heater core without first considering the failure of my valve. I don't want to go through the hassle of putting in new heater core then running car only to have a huge leak.
I'm not ready to purchase a new valve yet because...

http://tinyurl.com/ono4khq
cost: $$$254

Will keep you all posted!

[xcx4x]

Edit again

Nvm. Saw in previous posts. Going to remove.


Sent from my iPhone using Tapatalk - now Free

[xcx4x]

I've got this in the way. From all the research I did I don't recall running into this. Anyone have any ideas??

EDIT: forgot about seeing it awhile ago..just took that sucker off!