Heater Core--I think....

[mdburd]

Friday I was driving and the car was running perfectly.

I stopped at the bank to make a deposit and noticed the temp start to rise--which isn't totally uncommon when I'm sitting in 98 degree southern Colorado heat. (When driving the temp stays dead center on the dial)

Anyway--the bank is about a mile from home, so I started out and soon began hearing a hissing noise. Looked right, and saw a small greenish fountain coming from under the dashboard. Luckily, I was less than one block from home, so I coasted in, parked her in the driveway and shut her down.

Popped the hood--didn't see anything. Went back around to the passenger side and saw the antifreeze coming out under the dash--I slightly opened my flush and fill cap to let off some pressure. The hissing and fountain stopped, but it still dripped for a few...

My presumption is the heater core went. So I bought a new one to replace it with (I can return it if I don't need it--or get it to some other Fiat owner in need). However; I need some guidance on the replacement. Looking under there, I can't see an "easy' way to get to it and remove and replace it if necessary... Any help from someone who's done this is greatly appreciated.

Thanks:
Michael.

The car is a late 1978 model (141925)--she has some '78 bits and some '79 bits to her...

[adrians]

More than likely it's the heater valve, or the hoses that join to the valve or heater return pipe or the seals connecting the heater pipes to the heater.

When I need to do mine the valve was leaking as well as the rubber seal on the pipe.

Either way your going to need to remove the upper half of the center console and expose the heater box, then it's a process of working out which item has failed. At least it's easier on a LHD car - no pedals or steering column to worry about.

[adrians]

More importantly - YOU were actually depositing money at a Bank

[So Cal Mark]

the valve is the most common failure, and it can be replaced without removing the upper console. That's if your back is able to bend at odd angles

[mdrburchette]

I just did this on my 82 X19, which is a similar setup as on the Spider. I believe it will make it a little easier to remove the center console, especially if you have to replace the heater core but it can be done without removing it. The one thing I would suggest buying is the little rubber gasket that goes between the heater pipe and the core. I ended up taking mine apart three times trying to stop leaks because of these gaskets. Thank goodness Dave came down to help the last time since my patience was growing thin.

[mdburd]

Thanks, all--I appreciate the direction.

If there are any other trick to the getting in there, let me know.

Michael.

[baltobernie]

You definitely need to be a contortionist, but also check the condition of the two steel heater supply and return tubes while you have the valve removed. They regularly corrode when the cooling system has been neglected. You warm climate guys: remember to occasionally run the heater, or bypass it completely.

[htchevyii]

Soak the valve to core studs with P.B. Blaster. Half of mine broke off so I had to replace the valve & core.

[rlux4]

Same thing happened to me Trey.
Ron

[manoa matt]

I personally think everyone should eliminate and bypass the heater core. Regardless of the different designs, every heater valve I've come across has been faulty in some way. Either stuck open, stuck shut, or does not completely shut off.
The last three cars I removed the cores from had the metal tubes and valve rust welded to the core and couldn't be removed without damaging the core end cap.

The bottom line is, owners forget to open or run them for several minutes each month to circulate the fluid. More often than not the core and tubes are filled with a black sludge and corroded beyond the point of usefulness.

When the system is "in proper working order" the heat is either overwhelming or luke warm, and continues to alternate between the two until the operator gets fet up and closes the valve. I find heating and air conditioning in small classic convertibles un-needed accessories. Fortunately I live in an area where heat is never needed. However if I lived in an area where it gets cold, I'd still bypass the core. If your cold, put up the top. If your still cold, put on a coat. If your still cold, its time for long underwear or a hard top. You'd be better off with electrically heated seats.

Bypassing the core has several benefits. First it ensures circulation of coolant around the back of the head and block especially around #3 and #4. You will notice the engine runs a few deg. cooler. Metal temps in the head are consistent and even across the cylinders. There is less chance of head gasket failure between cylinders 3 and 4. The biggest benefits are never having to remove the center console, replace a $30 valve every year, lay on your back to work on the dang thing, re-install corroded metal tubes, or constantly worry the thing will fail and dump coolant on your feet.

[htchevyii]

I drive with the top down & heater on all the time, of course it's not so hot here. I also consider it a safety hazzard not having a functioning defroster. I know some have spoke of a bypass type heater valve that would still allow full coolant circulation, but I'm not sure how it turned out. PerformanceFiat offers a ceramic valve that he claims is beter.
http://www.performancefiat.com/catalog/ ... cts_id=356

[mdrburchette]

I prefer my heat to work too. Tonight was a good example. Clouds started rolling in and the temp dropped so I turned on the heat and continued to drive with the top down.

[launieg]

I couldn't imagine bypassing my heater core. Even on a hot (for us) summer day, a run into town in the afternoon can end in an hour's drive back in some very cool weather, especially along the ocean. Having the heater on (and a windbreaker and hat) makes for an exhilerating and wonderful ride back, especially if it is getting dark. Otherwise I would be coming home very chilled. Plus, we have little enough top-down weather up here to ruin probably half of it by having the top up. In fact, tomorrow I will leave for town at about 7 am with the heater on. It will be about 55 Fahrenheit. By 10 am it will be almost 80 and I'll have turned off the heater some time ago, but I might need it on the way home.

Oh, I suspect that is why both my spiders have working heaters - they have been used regularly because of our climate.

By the way, my son says it's not "cool" to have the side windows up when the top is down, but often I do it to enjoy the ride -same reasons. I stopped being cool a long time ago and some might say I was never cool

[kilrwail]

To me, the most enjoyable time to drive these cars is in the spring and fall in late afternoon and evening, with the top down and the heater on, if necessary. They run better in the cooler temperatures, we don't get sunstroke, and the sunsets are great with the top down. Like Launie, I've used my heater regularly for 31 years and never had a problem.

[baltobernie]

Reviews of the car usually mention the shoulder room benefit of a sedan-based platform, but the big heater core is a nice surprise for many of us, too. Compared to British roadsters of the era, the Spider's heater/defroster is (like the rest of the car) decades ahead of its time.