Overheating | Radiator fan issues | 1985 Feiro GT (Page 3/6)
82-T/A [At Work] FEB 04, 11:41 AM

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Originally posted by Hamfiero:

Sorry if my post was confusing. When I say figured, I don't mean concluded. We just were hoping that the radiator fan might start spinning if we get all the belts back on. This wasn't true with the fiero though. The radiator fan only spins if I turn on the ac. This is my main issue.



To be honest with you... I had an 87 Fiero SE / V6 (basically your car), and the radiator fan rarely, if ever came on. Even just sitting in the driveway, in 60 degree weather, the radiator fan wouldn't bother to come on because the car was able to keep itself cool. This was with a 180 degree thermostat though, which I don't really recommend anymore. But it had fresh 50/50 mix of coolant, a new water pump, and everything was perfect. Your Fiero should reasonably be the same in proper working order. If you're driving... (and not stop and go traffic), the radiator fan should never need to come on because the air going past the radiator should be enough to keep it cool.

These are the things I would check in this order:
- Replace your thermostat with a new STANT 195 degree thermostat.
- Check your cooling lines to make sure they are not bent and / or damaged (they run under the passenger and drivers side door threshold)
- Check the temperature fan switch (looks like below)
- Flush the radiator / cooling system. MAKE SURE YOU "BURP THE SYSTEM" when you're done!
Cliff Pennock FEB 04, 12:38 PM

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Originally posted by 1985 Fiero GT:

Yeah, and it would be perhaps 30 minutes to an hour (at most) before the coolant in the engine boils away and the engine gets serious damage from overheating, so the initial symptom would be overheating, which was the case here.



Not exactly. It's not a newly aquired car that overheated from the first drive. OP said it started when it got cold. He had been driving the car prior to that without problems. Something that is not possible without belts.


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Incidentally, considering he had "smoke" coming out the engine vents, doesn't necessarily mean he has a coolant leak



Unless the engine is leaking a massive amount of oil, smoke coming from the engine vents is almost always coolant. Almost always. If it's oil, that should be easy to spot because you will still see "wet" spots even after you haven't driven the car for a while.


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leaking around fittings and hoses, essentially a leak that leads vaporized coolant under immense pressure, but not the liquid form under the little bit of pressure it normally operates at.



It would not leak from fittings unless they leak. Fittings and hoses that don't leak can withstand the pressure with ease because it (should) never get higher than 16 psi which is when the radiator cap opens up.

So we agree he has a leak. The cooling system is a closed system. If there's a leak, it leaks liquid coolant, not steam since the cooling system should not contain any vapor. If it does, then again it means he has a leak somewhere and the car is really, really low on coolant.
Vintage-Nut FEB 04, 12:53 PM

quote
Hamfiero:
The radiator fan only spins if I turn on the ac. This is my main issue.



Then check the 'coolant temperature switch' by connecting the wire to the engine block or 'ground'. (This switch is next to the thermostat housing.)
*If the radiator fan turns on; replace the switch
*If the radiator fan did not turn on; check the wires from the coolant temperature switch to the radiator fan

'85 Radiator Fan Circuit (coolant temperature switch is the bottom on the page)


The Fiero Store V6 Sensor & Component Location
https://www.fierostore.com/Tech/Default.aspx?Id=99

------------------
Original Owner of a Silver '88 GT
Under 'Production Refurbishment' @ 136k Miles

1985 Fiero GT FEB 04, 02:19 PM

quote
Originally posted by Cliff Pennock:


It would not leak from fittings unless they leak. Fittings and hoses that don't leak can withstand the pressure with ease because it (should) never get higher than 16 psi which is when the radiator cap opens up.

So we agree he has a leak. The cooling system is a closed system. If there's a leak, it leaks liquid coolant, not steam since the cooling system should not contain any vapor. If it does, then again it means he has a leak somewhere and the car is really, really low on coolant.



What I'm saying is that the cold temperature is coincidental at most, or maybe caused the belts to become brittle and break, which then means the water pump is not spinning, and the engine is heating up without any circulation of coolant, thus boiling the coolant in the engine, as steam takes up much more space then liquid coolant, it rapidly over pressurised the engine, which caused it to leak at the next weakest point, a place that may not necessarily leak after refilling with liquid coolant and running at normal pressure. Like I said, there were a lot of symptoms, some connected, some not connected, if he had a proper mix of antifreeze, the cold has nothing to do with it, other then potentially making the belts brittle.
If the belts broke off, rapid failure of the cooling system would immediately result, well before the engine stopped running from lack of voltage, resulting in the coolant left stagnant in the engine boiling off as steam, escaping from whatever will leak when exposed to the force of boiling water. Point is he had a leak when all the steam escaped, he should be worrying about refilling his coolant system, checking operation of the thermostat, and making sure the water pump is pumping coolant and the belts are hooked up properly before wiring about a potential coolant leak that he may or may not have at normal operating pressure, that can be discovered/addressed when he is certain that coolant is able to circulate at all.

I think that the cold broke the belts, causing the now stagnant fluid in the engine to boil, rapidly boiling fluid created an exit path, if it was through the seating surfaces on rubber hoses, that could very well reseal once the pressure dropped back to normal, and his current overheating concern (with new belts) is likely caused by either a stuck thermostat, or (very likely) improper burping of the engine side coolant system, once the coolant is burped, and the thermostat is checked, then any leaks will show themselves, and can be fixed.
Cliff Pennock FEB 04, 03:38 PM

quote
Originally posted by 1985 Fiero GT:

What I'm saying is that the cold temperature is coincidental at most



If he has the proper coolant, then I agree. What I'm saying is that he claims he has been driving the car for quite some time without belts - which is not possible.


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If the belts broke off, rapid failure of the cooling system would immediately result, well before the engine stopped running from lack of voltage



Again, I agree, but he said he made a few short trips. Without a charging alternator, you would notice other problems very, very soon. That does not take hours. I remember my alternator failing once, and it took 30 minutes of driving (with my lights on) before my Fiero simply shut off. Before that I noticed all kinds of things. Applying throttle made the car bog for one thing.


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Point is [if] he had a leak when all the steam escaped, he should be worrying about refilling his coolant system, checking operation of the thermostat, and making sure the water pump is pumping coolant and the belts are hooked up properly before wiring about a potential coolant leak that he may or may not have at normal operating pressure, that can be discovered/addressed when he is certain that coolant is able to circulate at all.



I agree. But I'm sure he has a leak. It's takes quite a bit of coolant to make the steam visible through the vents (I know because I have a leak now just behind the thermostat housing). But before we/he can do any troubleshooting, he needs to take a picture and show us what he has done because his description doesn't make that clear at all. If indeed he has installed both belts as he says, then we know the old belts broke. That leads to everything you said above. But at least I can't make that up from what he writes. OP thinks the problem is caused by the radiator fan not spinning. Which is not true. As someone else mentioned earlier, a Fiero's radiator fan hardly ever comes on. Especially in the winter. The fact that it doesn't come on when it's overheating doesn't necessarily mean the temperature sensor or the radiator fan is faulty. If there's air in the system, there can be a huge temperature difference between the temperature sensor and the temperature gauge sender. Again, I know from experience...


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I think that the cold broke the belts, causing the now stagnant fluid in the engine to boil, rapidly boiling fluid created an exit path, if it was through the seating surfaces on rubber hoses, that could very well reseal once the pressure dropped back to normal, and his current overheating concern (with new belts) is likely caused by either a stuck thermostat, or (very likely) improper burping of the engine side coolant system, once the coolant is burped, and the thermostat is checked, then any leaks will show themselves, and can be fixed.



Exactly. If the belts broke, then the current problem isn't (only) caused by a sticking thermostat, but by an incorrectly filled coolant system (and we know he didn't fill it properly because he couldn't find the thermostat. Sure, his thermostat could be sticking now but replacing it won't solve the problem. If coolant escaped through a leak in the engine bay, then the system sucked in a lot of air when the engine cooled down. For now, he needs to shift his focus from the radiator fan to the (rest of the) coolant system. He needs to fill the coolant system properly, get the engine up to temperature, and find the leak - because there absolutely is one. And I bet ya that once he has done all that, the radiator fan also suddenly starts working.
Cliff Pennock FEB 04, 03:41 PM
So in short we agree on that he first needs to properly fill his coolant system, and then we'll take it from there.
Hamfiero FEB 04, 03:47 PM
Wow, I had no idea that my post was that confusing. As I said, I'm nowhere near a mechanic, so I'm sorry if my ideas aren't correct.

I'll try to respond to your comments to the best of my abilities:


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If both belts were missing, the car would not run at all.



Well, I managed to drive nearly three miles with both the serpentine belt and accessory belt missing through multiple stop-and-go trips. Once I got it off the interstate, I took the battery home with me and charged it up before returning and going as far as I could go without it overheating. So, it did in fact run with some assistance. It lacked power, I'm guessing due to the lack of a belt to run the alternator and keep the battery charged.


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So now I'm wondering if you call the water pump, radiator and radiator fan all a "radiator".



Hmmm, not really what I meant by that. We did not believe the water pump was in the engine bay. We had heard about other cars that had their radiators run by some sort of belt and pulley system. We assumed it worked something like this: somehow something in the engine spins the radiator fan, the spinning motion is transferred to the water pump as well, and lines are run back to the engine to cool it. Were we right? Of course not. It was just an idea of what could have happened as a side effect of putting belts on the pulleys. I'm not exactly sure what we were thinking of, but I believe it was something like a fan clutch. Again, we're not mechanics, so it was just an average non-mechanic human brain assumption of how cars work that turned out to be wrong. We knew the radiator and its fan were on the opposite side of the car and that it wouldn't be possible for it to work like this, but it was just a hope that fixing the belts would kill two birds with one stone.


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We are completely in the dark what you did here.



We put belts on the pulleys. I was pretty sure I said that, so I'm sorry if I neglected to inform you all of it. Again, we made a wrong assumption of how the car worked which didn't solve the overheating of the car. We thought that putting the belts on the car might cause it to stop overheating. This didn't happen though which is why I've asked this forum for help.


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Smoke coming from the vents isn't a symptom of overheating, it's a symptom of a coolant leak. There are no over-pressure vents in the engine bay. Overheating is a symptom of a coolant leak. So at least we have established you have a coolant leak.



This does seem like a logical way of thinking. I just don't understand how it could be right though as there is never any liquid under my car except for one time when I found a minuscule spot of oil (around half an inch in diameter) on the cement of a friend's driveway. Besides that one incident, I haven't seen anything else. I also have never seen the smoke coming from the engine ever whenever it is running at normal temperatures. It only smokes when it gets to 260F+. It's my assumption that if I did have a coolant leak, it would leak onto the floor beneath the car. Yet, I haven't seen a single drop of any fluids beneath the engine bay on level and inclined ground. Again, I'm not a mechanic, so this is just an assumption I've made with my basic understanding of how cars work. If you could provide me with more information regarding the smoke, it'd be greatly appreciated as I'd like to fix all of the issues with my car, but since it's only happening when my car reaches those high temperatures, I'm not sure it's much of a problem but more of an inconvenience at extremely rare times.


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Do you mean the waterpump or the radiator fan? And what's your logic behind the idea the radiator fan would spin once you install the belt?



I'm probably sounding like a broken record, but again, I'm not a mechanic. It was just a wrong assumption. I do apologize for saying radiator instead of radiator fan. I truly did mean radiator fan, but I guess I just forgot to type the word "fan" afterward. That is completely my fault, and I understand why it'd confuse you guys. I assume you guys don't usually get non mechanics on here who don't know the terms for everything, so it only makes sense for you all to be irritated. I also get irritated at those who are ignorant of my fields of study and try to communicate with me through completely incorrect terminology, so I completely understand how you all must feel.


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True, there are some very old/weird cars that have belt driven radiator fans. But those are all front-engine cars where the engine and radiator are in the same (engine) bay.



Yes, we realized.


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Actually, you have gotten several serious responses, but we are completely in the dark about what exactly the problem is and what you have done so far to try to fix it. Because again, the things you say you have done are unclear.



Indeed I have, and I am very grateful to 1985 Fiero GT for trying to help me in my troubled times. I plan to check my thermostat directly because of their response. I apologize for my hard-to-understand descriptions of my issues. I really just want to get my car running again as the weather gets nicer. My problem, or at least what I am thinking the problem is, is that my engine overheats after five to ten minutes of running. I haven't tried much to fix it as I was busy fixing another problem (missing both belts in the engine), and I have just now gotten to trying to fix it. There are two separate problems at hand, and I'm sorry if I got you all confused by talking about both in the same post.


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Not to be condescending or anything, but if you can't find the thermostat on a Fiero, maybe you shouldn't work on the car before you have bought a workshop manual or a haynes manual. If you open the engine bay, the thing is staring you in the face. The thermostat housing is one of the most prominent features on a Fiero engine and the writing on the thermostat cap should have given you a clue that it's part of the coolant system.



I actually do own a Haynes Fiero manual but couldn't find any of my issues in it. Thanks for the tip about the thermostat! We hadn't found the thermostat because we hadn't looked. One problem regarding the thermostat is that I can't open my trunk. Before the trunk became unable to open, I was able to get the right vent off so we could easily maneuver the battery. I don't have a key lock in the trunk as it didn't come with one. We were planning on getting one for it when all of this went down. Pressing the trunk release button on the dash doesn't result in anything; no sound and no open hatch. This was happening to us when we were trying to open it to get the battery out, so we found a video showing how you could unscrew the assembly and use a battery to "hotwire" the relay (probably not the right word, but again, I'm not a mechanic, and I don't even know how I would search to find out the actual word for it) with a dead battery. It did work once or twice, and we could see a little arc from the positive wire to the positive part of the relay. But when I tried opening the trunk when I got home with a new battery inside, it still didn't work. The "hotwire" method no longer arced, it just sparked. And when I say these words, arc and spark, the difference I'm trying to convey is that one had a little arc of electricity that you could see that made a little quiet noise while the other sparked out towards me with sparks of electricity. I checked the fuse box and the fuses were fine. I read that it could be the trunk release solenoid but I'm not sure how to get to it without having the trunk open. Might there be another way to open the trunk? I have a good battery in the car with a now-working alternator, and the vent that covers the battery is in the trunk.


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...where did you fill it with coolant? Overflow bottle? Radiator? Because if you have low coolant, trying to fill the system from those spots without opening the thermostat housing will not work.



Huh, that's strange. We were able to add coolant to the radiator. We filled it straight into the radiator and it drank it up. I'm guessing that's probably not a good thing.


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You describe problems that aren't problems (like the radiator fan not running all the time), situations that are not possible (the car running without any belts installed)



I wasn't saying that the radiator not running all the time was a definite problem. I just said that my non-mechanic brain just assumed that it was one. I apologize for being wrong, but I wasn't trying to confuse anybody. Also, the car did run without any belts installed with assistance. Without assistance, it wouldn't have run. I assume that's what you meant, but I guess there is a chance that my fiero just magically defies physics.


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So in order for us to help you, please start by making a photo of your engine and the "fixes" you have done so far and post it here.



Alright, can do. I haven't done any fixes for this particular problem as I'm still trying to figure out why my trunk won't open. For the trunk, I've tried doing a "hotwire" method which worked initially but not anymore. For the overheating, I've just put the belts back on. Wasn't a fix, just a hope. Here is a link to the video I watched that gave me the "hotwire" ing method: Unlock Pontiac Fiero trunk without keys. 1984 SE | Tom Jackson. I've also attached some labeled photos to hopefully help you all understand my situation better.

Trunk release relay that sparks:


Lack of trunk key mechanism and broken brake light cover and diffuser:


New belts and taken off vent:



Thanks for the response! It has helped me dearly. And again, I'm sorry for being confusing.
Hamfiero FEB 04, 03:58 PM
I think there's been a miscommunication (more likely multiple).


quote
Originally posted by Cliff Pennock:
What I'm saying is that he claims he has been driving the car for quite some time without belts - which is not possible.



I'm not sure we have the same idea of short trips. It took about two five to ten-minute trips to get it off the interstate and into a parking lot. Once we got it there, we took the battery home to charge it. It then took one ten to fifteen-minute trip to get it from there to home. By then, it was smoking extremely bad out of the vents and the battery was nearly dead.


quote
Originally posted by Cliff Pennock:
Again, I agree, but he said he made a few short trips. Without a charging alternator, you would notice other problems very, very soon. That does not take hours.



It was only around 20 to 35 minutes of driving. I could very easily tell that the battery was dying as I could barely see my dash lights in the evening.

Hopefully, this clears some things up.
Vintage-Nut FEB 04, 04:25 PM

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Hamfiero:
One problem regarding the thermostat is that I can't open my trunk.



Immediately STOP driving the car! You MUST open the engine bay to fill the coolant system!

The Fiero coolant filling procedure is From the Thermostat Housing - NOT at the radiator.
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Edit - To me, I believe it is too late and this V6 engine is very nearly dead from critical errors............

[This message has been edited by Vintage-Nut (edited 02-04-2024).]

1985 Fiero GT FEB 04, 04:30 PM

quote
Originally posted by Hamfiero:

I think there's been a miscommunication (more likely multiple).


It was only around 20 to 35 minutes of driving. I could very easily tell that the battery was dying as I could barely see my dash lights in the evening.

Hopefully, this clears some things up.



Very much so, in your picture of the battery vent cover, you can see the thermostat cap, nice and shiny, that is where you need to fill up your coolant, the Fiero has 3 high spots joined by tubes underneath the car, the engine, radiator, and passenger heater, that is why you need to fill out from the engine with the nose Ponting downhill, as the engine is the highest point, and just filling the radiator will literally just fill the radiator, simply refilling it properly will likely fully solve your problem. If not, or if more new leaks are discovered, that's what we're for!