rusty part under passenger dash

[jskinner96]

One of these days I'll figure out how to post pics but for now I've given up and I'm sure someone will be able to easily identify what this part is. I have a severely rusted part under the passenger dash that has a cable running to it and a hose connects to the back of it and then goes through the firewall. I'm at a loss as to what this part is.

[18Fiatsandcounting]

That sounds like the valve for the heater core inside the car. The cable goes to one of the levers in the lower central console (near the handbrake), and the hose goes into the engine compartment to a coolant loop. The other end of the valve is connected to your heater core.

This valve is a common source of problems, and also a very good way to separate mere mortals from the occasional gods that walk amongst us. In terms of getting it replaced, and getting it to work properly. But, as with life in general, we have work-arounds to allow the mortals to ultimately triumph.

-Bryan

[RRoller123]

Just a side note:

I noticed when I bought my car years ago, that there was an occasional slight smell of coolant inside the passenger compartment, and I was worried that I had the dreaded leak. There probably was a little seepage, most likely from the valve never being used, never being opened or closed, just sitting there static, year after year.

Initially I worked the valve open and closed a few dozen times and then regularly opened and closed it while driving. I still do this almost every time I drive. Run the heat up through the dash vents, even in hot weather and you don't notice it. (But run it to your feet and it will burn the skin right off your foot.)

So it has been 9 years now, and there is no leak at all. I believe that these valves need to be used regularly, and that lack of use causes them to leak. If they are opened and closed regularly, they seem to seat in properly, and it really seems to help with this problem. In my case, it apparently even stopped a very minor seepage.

[jskinner96]

Thanks for the info. And it makes total sense now. This car has been in Florida since 1985 so I'm doubting that heater has had a lot of use. And it looks like there could be a little seepage coming from it since it has such a large coating of crustiness around it. I'll make sure to move the levers around often. Is this something that's pretty easy to take out and clean up? It looks like it may have a gasket in the back where the hose connects so I wasn't sure if I should clean it up and replace that gasket? Thanks again.

[18Fiatsandcounting]

Is this something that's pretty easy to take out and clean up?

Well, I can't speak for a "newer" spider like yours, but at least on the older model years, the heater core and valve can be a royal pain to remove and replace. At least on the older models, the middle section of the lower dash has to come out (where the radio and such is), and then you have to contort yourself to work upside down in the passenger footwell. It's actually easier if you remove the passenger seat, put a thick blanket on the floor, and lie on that as you do the work.

To be honest, since you're in Florida and likely don't need the heater, the easiest thing to do is just leave it. However, this isn't a long term solution as it can really start to leak at some point in which case you'd need to do the work anyway. I leave the choice up to you, and we'd be happy to walk you through the process if you choose to fix it.

Normally I don't advocate ignoring a problem, but this particular job is one of the more challenging ones on a Fiat.

-Bryan

[jskinner96]

Thank you Bryan. I have so many other pressing things to work on so I think I'll ignore it at least for a while. I just got to poking around under there and it was so ugly I thought it may need some attention. But know what it is and what it does now I think I'll let it go for w while while I work on some other things. I'll eventually replace that middle console and the dash as well as my carpet and seat upholstery. So maybe when I decide to do that and have all that stuff out it would be a good time to take on that challenge. You know what they say, how do you eat an elephant? One bite at a time. Thanks for the help.

[18Fiatsandcounting]

An excellent plan, and yes, if you have your console and dash taken out in the future, that would make the heater core / valve job infinitely easier. Well, maybe not infinitely, but definitely a lot.

-Bryan

[RRoller123]

You could just bypass the whole thing in the engine compartment too. Especially if it is staying in FL and the heat won't likely ever be used. Very easy to do.

[spider2081]

I find driving while its raining the defroster is often needed to remove fog/condensation from the inside of the windshield. The heater core provides the headed air for the defrosters best performance. I have tried opening the vent windows but then the rain drips on my left leg.

[RRoller123]

That's a good point, removing condensation. Too bad there isn't a tiny blower for the clock and tach gauges....

[DieselSpider]

I find driving while its raining the defroster is often needed to remove fog/condensation from the inside of the windshield. The heater core provides the headed air for the defrosters best performance. I have tried opening the vent windows but then the rain drips on my left leg.

I'm using a small 12 volt electric heater to take care of that right now. The previous owner had already bypassed the core.

For the OP if its just rusty and not leaking I would leave it alone until I was ready to replace both the heater core and the valve. Once you start torquing the bolts on the valve many times the core is immediately going to fail and if not then it will fail in the near future.

[jskinner96]

okay, I think I'll hold off on it for a while. I have so much other stuff to do that can take a back seat for a good while. Thanks for all the great advice.