coolant dribbling under dash

[timspider]

With temps above freezing briefly yesterday I got a good wash in for fifi (my girlfriend named her- I kinda like it) and got a chance to take a run around town with the new carb/exhaust/starter/headlight kit. Engine with 90,000 miles running really nicely again. Starter from csaba is fabulous. headlights way brighter- also did the brown wire fix. everything good.
I got home and found our old lexus had a dead battery. Busted out the trusty cables and got her going. My girlfriend was a little impressed that the car that is always in the barn getting worked on was able to help.
And yes, I was even a little proud. Then I got back in after disconnecting the cables only to notice coolant leaking under dash on passenger side. I've been worried that the heater core might be going as I've been getting a little fog on the windshield when the defroster is on.
I'll put a couple pics here- the under dash one shows where the leak was. It was right behind that little silver thing which I'm guessing is related to opening and closing heater doors (I have to get a shop manual- I know).
So before I take the dash apart to replace the heater core, does anybody have any wisdom to share?
Like an easier solution maybe?
the leak might just be from where that pipe attaches- so maybe just a new gasket for that joint?
dunno, but wiling to learn

[TX82FIAT]

Tim, you can see the coolant leak on the top of the heater valve. This is a common failure point on these cars. The one pipe looks good going into the heater box. You mentioned fog on windshield when defroster is on. That may as you have indicated mean a problem with the heater core. One of the issues is that the original heater valve is not available anymore. You will need to use an alternate valve with slightly different dimensions than the OEM for the spider. This results in the need for new pipes or slighly bending the pipes so they go through the firewall just above the valve properly.

For a temp fix go to home depot and buy a brass pluming elbow (I think 1/2 inch) and detach the two cooling hoses from the inside of the firewall. Re-attach the two hoses that were previously going into the firewall using the elbow to bypass the heater core entirely. Bleed the cooling system again. this way the car is drivable while you drain the coolant from the heater core, inspect the heater core and obtain replacement parts. We know you need a valve at this point

Don't take the upper dash out, work from the bottom up. Take the lower center console and the center console out. The heater box clips up into place. Once your remover the heater pipes metal retainer plate on the firewall you can drop the heater box out and inspect the core to see if you need a new core.

A few things to consider: Pull up the carpet and take a look at the floor to make sure this is a new issue and not one that may have caused some corrosion. Be careful with the heater box and the clips. the plastic is old and can snap if you exert force. If you are a big guy you may want to consider taking the passenger seat out for some working room.

[Exit98]

TX82FIAT covered all the bases. They are a real PIA to work on but its doable and way easier than a modern car. There are a bunch of posts covering this, I think half of us have dealt with the issue. The other half will too, sooner or later.

Check out this post and take a look at my idea for dealing with the rear most 10mm bolt back behind the valve:

http://www.fiatspider.com/f08/viewtopic ... ater+valve

A new core and valve isn't real expensive. Since you're going in there anyway why not take care of both issues once and for all?

Let us know how it turns out.

Good luck.

Oh yeah, I definitely recommend pulling out the seat.

[timspider]

wow, excellent info- thank you thank you
I'm thinking of putting "back to the pole barn" in my signature- on my way again

[RRoller123]

Reading this has got me to thinking that we should be putting in a bypass on the heater line, in the event of the inevitable inside the cabin leak, it can be easily and quickly shut off. I think I will do this when my new engine goes in, hopefully this Spring sometime.

Pete

[SoFlaFiat]

Tim, I have removed the entire system from my car if you need parts, going cheap... Let me know

[timspider]

multiple cans of worms.
hell of a time getting that heater box out, and I haven't even tried getting the impossible to get at nut by the firewall yet. So if I'm supposed to get this black plastic box completely out, I have one control cable to somehow detach from the inner housing and the electrical for the fan to disconnect?- not sure how to do either at this point.
Good news" I can see the heater core and it was indeed leaking as I thought so it's a good time to get that and the valve replaced while I'm in here. I have them sitting here. On the one hand this looks so simple- I can see everything I need to get at- I already have the parts.
I must be missing something here, like mechanical acumen.
I'm also going to blame some of this on the 8 degree temp in the barn.

So do I just leave this plastic box dangling and go ahead and pull the core out? I'd rather have the box out of the way but not if it's impossible to get that control cable back in. Do I have to cut the power wires and re-splice them?

Once the big console came out, I could see the entire under boot looks to have disintegrated, so I'm replacing that and probably the main boot too.

And then there's the wiring. ee gads. I just found a 4th black wire stripped and just hanging around loose in that rats nest. there is a purple loosely hand twisted on to a black, there is a yellow spade connector loose, and there are 4 different small white connectors that are open.
I think I'll post in wiring for the rest of the electrical details and questions. I have several.
arrrggg
thanks

[TX82FIAT]

Tim, the box is in two parts and the bottom part should have enough room to unhook from the top and come out. It will not move until you unhook the pipes going into the firewall as it is often a tight and exacting fit. You don't need to unhook the top defroster flap cable. You can open a clamp on the inside drivers side transmission tunnel to gain soem slck to move the cable for the bottom portion. If center console middle and bottom are out of the car you should be able to slide the bottom portion of the box to the side to insall new heater core. Don't over tighten the bolts for the pipes. Use new rubber seals where the pipes connect to the box and the valve.

As for the wiring, based on a previous post I'm not sure what to tell you. The fan motor to the best of my memore has a connection box that should be disconnected to free up the fan motor. You should get a wiring diagram. Search brad Artigue wiring diagram fiat spider and you should find a pdf file to download for the wiring diagram.

[timspider]

Ok, heater box out. Little metal flapper door scraped, sanded, primed and painted. Got some ductwork sealant for the top piece to seal nicely at the dash.
now I'm wondering do I need to switch my sensor line to my new valve?
If so, any secrets to doing that?
Lastly, just broke the tiny plastic piece that holds cable for the lower heater door opening.
any tricks or workarounds? Or do I now need to source this tiny piece?
Thanks as always
tim

[timspider]

Today was the big day to get the core back in. Took my time refurbing that little fresh air door, which was rusted in the slightly open position. Works great now. Switched out to a salvaged fan and casing, tested the fan and all that looks good.
The last time I attempted fixing a heater core it was in a 1980 Chevy Monza, and it was never right after I had that dash apart, so I've been gun shy on this one.
I just kept going through old heater strings on this forum and soaked up everything I could and eventually, after about a week of re reading the same stuff, started to feel ready.
There was one string here where someone posted about putting together the whole sub assembly first, and just bending the one tab slightly to get it in. I was worried about that tab so kept it warm, and to my shock, the whole assembly slid right in, nice and snug but not bowing out the box (3/8 medium compression sticky foam was what I settled on). The under piece then slid in and all 4 clips were a piece of cake. Shock. Nervous giggle. Firewall grommet went back on fairly easily.
I now know I need to buy a pre-bent rubber pipe for the short pipe at firewall- thought I could do that, but I can't get it to not collapse at the bend.
I'm fine with that. I can't believe that's all that went wrong.
Tomorrow, I will start the car and we'll see if my gaskets are as awesome as I hope.
Thank you everyone for invaluable advice.

[perthling]

Neat job, looks like you got it all sorted without too much drama. It's painful working upside down on this stuff but as you found (and fixed) a bunch of other issues it looks like it should all come out roses.