So they supposedly flushed the cooling system when rebuilding the engine. They said some crap came out but not much. But I think I'll get it double checked by another shop.
Did I mention I had the same problem before the rebuild? I even linked my old thread some posts ago. That was with the old water pump which also wasn't that old, only a few years. I think it's an Airtex if I remember correctly and it had the metal impeller, same as the new one.
EDIT: I guess a blockage inside the block is unlikely since it is a rebuilt engine. I haven't driven that much without the thermostat but it seems to work awesome without it if you ignore the long get up to temp time from a cold start.
EDIT2: I do think a blockage in the heater core is probable. And it is the "short circuit" as we call it here since it's before the thermostat. However I guess I would never have much cabin heat if that was the issue? Is still an air pocket a probability from all these posts or are you guys certain it's flow?
[This message has been edited by cebix (edited 11-09-2019).]
If it runs ok without tstat, drive it that way for a day or two. Meanwhile, check the tstat in a pot of hot water and see how it acts, when it starts opening and when its full open.
Keep checking coolant level.
[This message has been edited by olejoedad (edited 11-09-2019).]
My both previous tstats (Stant) didn't pass that test and they were both new. They didn't open at all in a pot of boiling water. Could they also need some pressure? One I drilled through to have a small flow of water. The symptoms were the same. Now I have a Gates one and didn't check it that way yet. But I do have flow through the rad, it's hot plenty so I guess it's working alright?
[This message has been edited by cebix (edited 11-10-2019).]
All right, drove it for an hour around the city with no thermostat. Here are my observations. It's 42F here outside.
1. It took forever to get up to temp but that's understandable. Good 15-20 minutes until the temperature gauge reached the second mark. Was turning heat on and off at this time to check heat but not to rob the engine of its temperature in this state. Heat was good even very early on. When up to temp it was blowing very hot like it should I guess. After this it runs great, no sudden temp rises or drops like with the tstat in. 2. However after idling for a minute or two it will slowly creep up to almost 220. Didn't stay around for it to stay higher but it would come down slowly to the second mark when driving around. Really slowly I guess, slower than it should? I stopped for gas, it took a few minutes while the engine was shut down. When I turned on the engine, the rad fan was blowing (it wasn't when I shut the car off) and the temp was a little above 220. Gave it some gas getting off the pump stand and it fell very quickly to the second mark just like with the t-stat it. Then again with driving no fluctuations but at idle it was rising slowly again to 220.
All hoses are hot and stiff. Couldn't check the coolant yet as the engine is still hot. Rad hot to the touch, rad cap plenty hot. Overflow tank didn't overflow, no noticable hisses, leaks. The hissing I was describing before I'm not sure of now - it might be something else since I can hear it coming from the engine too... but I guess it still might be an air pocket.
Do you guys have any thoughts about this?
EDIT: Checked the thermostat in boiling water... it does NOT seem to open. It stayed for a while in the water, I pulled it out and in again... nothing. What the hell, do I have 3 new broken thermostats or does it need pressure or whatever else to open?
[This message has been edited by cebix (edited 11-11-2019).]
EDIT: Checked the thermostat in boiling water... it does NOT seem to open. It stayed for a while in the water, I pulled it out and in again... nothing. What the hell, do I have 3 new broken thermostats or does it need pressure or whatever else to open?
It is a 195* thermostat.....boiling water is 212*.... so the thermostat should be open. no pressure required.
Would I get a hot radiator and hoses, etc. if it wasn't opening in the car? If it wasn't opening ever wouldn't have I overheated a long time ago on the highway?
[This message has been edited by cebix (edited 11-11-2019).]
Yes, one normal Stant, one Stant SuperStat 45819 and now I bought a Gates 33529S since it was supposed to arrive here the quickest. All bought from rockauto.
So if it's stuck all the time is it possible the engine would run normally on the highway for hours?
[This message has been edited by cebix (edited 11-11-2019).]
All right... buying a new thermostat then. Will return to this thread in a week or two when it arrives hopefully and see if it helps. I think I'm gonna try ACDELCO 12T50E for a change.
This time I'm going to test it in boiling water before putting it in the car.
EDIT: Just to be sure - what I described when I was running without a thermostat sounds normal?
[This message has been edited by cebix (edited 11-11-2019).]
I think it should have gained temperature faster than you experienced without the stat. You may still have a flow volume issue, but lets worry about that after you get a properly working thermostat.
Do yourself a favor and lose the Rock Auto contact information. Other's experience may vary, but I have never had good results with what they sell.
Does anyone following this thread have a known good t-stand they can send this fellow?
Yeah it's a hit and miss with Rockauto for me, other then those pesky thermostats the only big issue I've ever had with them was a wrong flexplate and they issued a refund without wanting it back, so that was okay I guess. No shipping cost and tax return though. But they're pretty much the only store I've found that ships internationally and I've been buying from them since 2011. Autozone, O'Reilly, Autopartswarehouse, don't offer international shipping. If you guys use any other stores, please state their names, I'll see if they offer shipping outside USA. EDIT: Fierostore and Summitracing ship too internationally but their quotes are twice or sometimes more than what rockauto proposes.
Just a thermostat is $7.99-$17.99 shipping cost according to Rockauto to Poland. If anyone has a good known thermostat I'd be willing to purchase that.
Patrick, I already have one that is also stuck closed so not sure of trusting them again.
EDIT: Just checked my coolant as the car cooled down. It's full at the thermostat cap - just at where I filled it today when removing the thermostat.
EDIT2: Ordered a SuperStat 45819 again, let's see what it does. Yeah, again from Rockauto. Should be here by Friday...
[This message has been edited by cebix (edited 11-11-2019).]
I rechecked my old order and it is the same number. So I just thought what the hell, I'll buy it again and see how it goes even though I obviously wasn't satisfied with that previous one.
[This message has been edited by cebix (edited 11-11-2019).]
I rechecked my old order and it is the same number. So I just thought what the hell, I'll buy it again and see how it goes even though I obviously wasn't satisfied with that previous one.
Well, I suppose there can always be a dud. That's unfortunate.
It's too bad that Rodney Dickman is apparently no longer still selling these particular thermostats. After being made aware of what you've gone through, he probably would've dropped a new one into a pot of boiling water to double-check it before shipping it to you.
[This message has been edited by Patrick (edited 11-12-2019).]
Yeah, I've bought some parts from Rodney over the years, mainly suspension stuff. All my ball joints and tie rods and tie rod ends from him are good still.
All right, the Superstat came in. Checked it in boiling water and voila, it opens! I put it in, go for a drive and nothing's changed... Almost pegged the gauge to red however after that it seemed to settle a little. I got into heavy traffic and was fluctuating wildly between 220 and the middle spot between the second mark and 220. After a while it kinda settles there in that middle spot between those lines. So I guess it's somewhat better? Still the gauge is not steady and kind of wobbles when without the thermostat it was very fluent. Any ideas about these symptoms? Still air somewhere or a blockage? Thanks.
[This message has been edited by cebix (edited 11-16-2019).]
Not really at the moment. Going to look them up, if they're not too expensive, maybe I'll get one. Still all the hoses are plenty hot and stiff under pressure, rad cap too is hot. There's heat from the heater but it's going a little cooler when idling, not cold though like previously. When revving it gets somewhat hotter. I'm still thinking there is an air bubble. After cooling down and starting the engine again it does go above 220 and then it "kind of" settles down from there but a lot of fluctuation. Without the thermostat there was no fluctuation at all, just steady rising and falling down slowly like in newer cars I guess.
Originally posted by cebix: After cooling down and starting the engine again it does go above 220 and then it "kind of" settles down from there but a lot of fluctuation.
There are cold and hot spots in the cooling system because it is so big. The thermostat is closing when the coolant is cold....it heats up and the thermostat opens...in comes more cold coolant....thermostat closes again. It's a special Fiero feature with the engine and radiator so far away from each other...
So this is normal behavior for your Fieros too? I'm not sure they acted like that from the factory in the 80s, people would go nuts. I think I'm going to try to shoot a video of the gauge while driving so maybe you guys can judge how it's supposed to be.
I'm looking at some youtube POV videos and most guys' gauges either don't work or they're running dead cold. I don't know.
[This message has been edited by cebix (edited 11-16-2019).]
There's heat from the heater but it's going a little cooler when idling, not cold though like previously. When revving it gets somewhat hotter.
So this is normal behavior for your Fieros too?
None of the several Fieros I own has ever acted in this manner.
Have you tried this yet? If not, why not? It's a simple process.
quote
Originally posted by Patrick:
If it was my Fiero, I'd remove one of the hoses from the heater core and flush and then back flush the system with a garden hose. This would at least tell you if you have a blockage somewhere in that part of the system, and maybe it would also push out whatever the blockage is.
Keep in mind that you don't necessarily need to disconnect a hose up front from the actual heater core. If it's easier to disconnect a heater hose in the engine bay, do it there instead.
I also guess your gauge is pretty steady and moving fluidly and not going into the red just to fall down with a blip of throttle down to 220 and less?
That would be a correct guess.
quote
Originally posted by cebix:
Haven't tried to flush the heater yet. Can't get those hoses off anyway, and would probably have to cut them.
My experience has been that even if the last inch or so of a heater hose needs to be cut off in order to remove it, the hose is still plenty long enough to reattach it.
I'm going to try to shoot a video of the gauge while driving if I find a safe way to do so, so maybe it'll become clearer how it behaves. Don't really have the means to flush the heater right now so I guess I'll drive around for a few days and see where it goes from there.
Not really sure how to shoot a video durig my commute showing the dash all the time. Might have to fabricate some kind of phone holder.
I've been commuting a few miles these past few days and no driving besides that. It's 40F here. The car still goes to red on first heatup after about 3 minutes from dead cold and wants to go up there all the time unless I give it some throttle. However it does become civilized after about say 15 minutes of driving and idles forever with the needle on the second mark. Guess it's burping itself? This would not be a symptom if it's clogged somewhere? Unless it unclogs after some heating up and clogs itself when cold? I'm going to flush the system this weekend and try to flush the radiator and heater core and see what I get.
All right, been flushing the heater core and it flows all right I guess. Some rust particles came out but not so much to clog it I guess. Going to leave it overnight filled with vinegar to see what comes out tomorrow.
However! This is what I found at the bottom of the overflow tank:
Looks like sealant? No idea how much of that is in the system. The overflow hose also looks fishy and wasn't as tight as I would like at the rad fitting so going to replace it. Going to try to flush the radiator but have a feeling that the hoses under the car may be clogged with this stuff inside. Are they stainless steel? Is it safe to use NaOH to clean them inside? The radiator is aluminum so that's out of the question. Anyway looks like I have to overhaul the whole cooling system.
Not really sure how to shoot a video durig my commute showing the dash all the time. Might have to fabricate some kind of phone holder.
I've been commuting a few miles these past few days and no driving besides that. It's 40F here. The car still goes to red on first heatup after about 3 minutes from dead cold and wants to go up there all the time unless I give it some throttle. However it does become civilized after about say 15 minutes of driving and idles forever with the needle on the second mark. Guess it's burping itself? This would not be a symptom if it's clogged somewhere? Unless it unclogs after some heating up and clogs itself when cold? I'm going to flush the system this weekend and try to flush the radiator and heater core and see what I get.
The gauges, especially at their age now, are notoriously inaccurate. I’ve changed senders and temperature gauges in my 88GT more than once and it still goes nuts. The way I test the real temperature in the system is I put a scanner on the ALDL and see what the ECM is seeing. Do you know anyone with a real time data scanner?
Edit, remove scanner link.
Any time I’m reviving a long dead car or I need to be sure everything is working properly, I put the scanner on and see what the ECM is seeing.
[This message has been edited by fierobear (edited 11-23-2019).]
Flushed the whole system, radiator, heater core. No signs of blockage and pretty much no crap came out. Got a feeling I got lucky with the reservoir crap as it probably was added to that tank and never got sucked into the system. Cleaned the reservoir tank, replaced the hose from the rad cap, burped the system per Patrick's recommendation... and no change, nothing. I installed that fitting you guys told me not to... I cut the heater hose a little short and it served as a good connection. So I used it as a bleeder valve and it worked good, let out a lot of air but the symptoms are the same. Might look at that IR gun though, they're not that expensive and may come in handy for other things.
Maybe indeed there's an electrical issue with the sender or the gauge itself? Or I did a crap job at flushing the system or there's still air. Got to say, there's no sign of overheating other than the gauge reading. Might try to get an ECM scanner but that $190 is a little too expensive for me. Or I'll try to install an external temperature sensor for reference.
[This message has been edited by cebix (edited 11-23-2019).]
