very high temp after 10% od pulley and new 180 t-s

klsoneSC

Registered User
Ok, I am about to go insane with this project! I Installed a 10% OD pulley on my SC and I HAD to take the t-stat housing off, I could not fit any pulley puller under there. So the car began leaking from the t-stat housing (happened last time I replaced the thermostat) so I got some gasket making material and ultra copper RTV and sealed it up fairly well. I also put in a Stant 180 degree t-stat with a drilled burp hole in it. So then the heater hose began leaking and I had to remove and retighten it and I added some RTV to the seat of the hose and it stopped leaking. Well, I let the car run for about ten minutes and NOW MY TEMP. GAUGE IS UP IN THE RED!!! My fan was not running, but I am unsure at what temp it actually turns on. Should my fan be running??? Does the 180 degree t-stat have anything to do with the extreme heat??? Should I not have drilled the burp hole in it??? PLEASE give me some ideas here guys, I am ready to kick the ***** out of this car!!! Thanks for your time and help!!!!!!!!
 
fan should be on

The fan should definitely be on by the time the needle gets in the red zone. Dont drive it like that until you fix your problem, its very likely to blow a headgasket or warp a head. First see if the fan comes on when you give it 12 volts, if it does then i would check the IRCM. Also there is a fusible link on the fan near the starter relay i believe (not sure) that could be toasted. Check all of those things, and of co urse make sure your fan is plugged in all the way.

Kyle
 
Thanks buck! Any other ideas anyone? The fan worked fine before I started this project. What could have made it short out or break? Spilling coolent on it? I didn't spill much but could that be? How exactly do I test the fan? I am taking a Automotive Electricity class at college right now but I am a real novice and am uncertian on how to test the fan. I will talk to my teacher Wed. but I would like to try everything I can to get the car working again!
 
OK, I went out and turned the AC on, and the fan comes on! I turned the vent on, and the fan comes on! The temp gauge stays in the normal position on the "m" with the air or vent on. As soon as I turn off the air, the fan stops and the temp gauge goes to the red. The pulley for the AC has a front plate thing (I hope you know what I am talking about) that turns ONLY when the AC is on, but mine turns for a second, then clicks and stops suddenly. It is a very loud click and the RPM's drop by ~100 and I feel the car shudder a bit and lose some power. Is the clicking normal or should that front plate be constantly spinning? I also noticed a ground strap on the passanger side chassis about 3 inches back from the fan going from its ground point to nothing, its just hanging there? Any ideas? Sorry about the length but I want to make sure you can understand and help me out. Thanks SO much for your time!!!
 
Makes sense

The click you here is the compressor ,it does not run all the time that your ac is on but is being directed by where your climate control is set,the fan however should stay on at low speed the whole time . If you were driving with the ac on the fan will run until you get over 40 mph, that being said ,if your going into the red and the high speed relay on the fan is not kicking in then you definitely have a relay problem between the ircm and fan. the low should come on at 220 and the high at 228 degrees.

p.s. 180 t-stats will need a fan program of some sort to get max benefit,especially with a 10 % pulley which is creating even more heat in IC tubes,may need to back down to a 5 % pulley but thats not my area.......... Guys ?????
 
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The fan does stay on with AC on. The IRCM has a date of Jan. 1997 so it has been replaced fairly recently. I am thinking about doing the "cut wire 14 and add switch" mod and have been researching that for a few hours now. Looks promising. I have never heard about a "fan program", any other insights??? I have a 91 and it seems everyone and their grandmother are running 10% OD pulleys. The 5% is stock on my car (I think I read that here). Anyway, please keep the ideas comming guys! Thanks.

Kyle
 
Kyle,

It sounds like you have a big pocket of air trapped in the cooling system. Jack up the front of the car and unscrew the plug thing that burps it. Keep adding coolant a little at a time until you get all the air out.

Another possibility is that you installed the thermostat backwards and it's not flowing correctly.

David
 
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by fan program i meant EEC tuner or chip that makes the IRCM think that it needs to turn the low speed on earlier. Dave is the man and has you barking up the right tree. I want to do the toggle switch/ 14 pin manual overide as well sounds like the cheapest way to go.
 
Pull codes. Sounds like if the fan comes on when the A/C is on but isn't coming on other wise, then you're not getting a signal from the coolant sensor which well could have been pulled off whenever you did the work.
 
The coolant sensor that operates the gauge and the one that supplies info to the EEC are not the same one. The gauge in the car could be reading hot and the sensor that tells the EEC when to turn on the fans may not be surronded by coolant, but air instead.

This all started after installing the t-stat, so there is most likely a connection. Don't start messing around with ICRM wiring and fan over rides until you know what happened. I still think it's trapped air or something wrong with the t-stat.

David
 
When you got the Stant 180 did you remove all the clear plastic on the T-Stat itself. I just put a stant 180 in my friends 94 SC yesterday and it had a plastic shrink wrap on it I had to use and exacto knife to get it all off.

We cut pin 14 on his ircm and it runs the low speed fan all the time I did this to my car too but I have a 195 T-Stat that I just put in. I removed the little ball from my t-stat so it has a hole now to vent. The 180 Stant didn't have one, and I didn't drill one.

You didn't mention venting the air out of the system and like Dave mentioned I believe you should do that.

Its a 13mm bolt. Loosen it up a bit till you can see the hole in the threads. Start your car, when coolant comes out the hole, tighten the bolt down snug.

Also the sensor in the t-stat housing is the temperature switch, its only purpose is to send a signal to your gauge in your dash. The coolant temp sensor is the one that send the signal to the cars computer.

Mine w/ the fan mod and 197 T-Stat runs about the O on NORM on the temp gauge.
 
OK, I am about to go out and try burping it like you said Dave. I installed the t-stat correctly and believe all the shrink wrap was removed. I thought I did the burp thing right, like it says on that white cap "remove before radiator refill, install before engine start" but I did not think you were supposed to turn the car on without it totally tightened. So I should loosen that burp bolt and start the car??? And wait for coolent to come out of it? I did turn the car on with the radiator cap on like the t-stat instructions said, is that to remove air or what? Anyway, I hope everyone doesn't mind the length of my posts, but I like to give as much information as possible. Thanks for all your help.

Kyle
 
I have started up my car w/ the burp screw out. The white plastic cap, **** I threw that away.

Do like dave and I said. Start it with the screw loose, then when coolant comes out snug it up.
 
OK, Scott, I'm going to do it right now! How long would you estimate it should take for the fan to come on with the car just sitting (in minutes)???
 
Well, that didn't work guys =( The gauge went up, check gage light came on. Could it be that the fan has never worked and I just never noticed it driving becaues of air flow through the radiator? I don't sit in traffic much and right now the car is just sitting and running in the garage. Would I have noticed the gauge go up while at a stop light? Where is the other coolent temp sensor (the one not on the t-stat housing)?
 
sucks

That sucks man. What I would do is find out why the fan isnt coming on. The other sensor is called the ECT sensor, and is located on the front side of the intake manifold. There was a picture of one a week or so ago on the board, with another guy confirming where it was. If you could find that post maybe you could check it out, or do you have a manual? At the least you should buy a Haynes manual from Auto Zone or Pep Boys or something of the such for like 15 bucks. It will help you. I bet it is more something like the IRCM. Since the fan comes on when you turn on your AC, that means the fan motor is good. So it is most likely either: A.) IRCM module is bad. B.) ECT sensor may not think the engine is hot so doesnt tell fan to come on?? C.) Maybe the fusible link burned up? I am not 100% sure on any of those, but that is definitely what I would check into first. Actually now that i think about it, its probably not the fusible link, because if it were burned up the fan probably wouldnt come on when you turn on the AC, but not sure. I do know one thing though, DO NOT drive your car until you can keep the temp in the NORM range, preferably around the O in the word NORM. If you drive your car that hot you are asking for problems. You need the fan to come on. Cut the #14 wire for now if you have to, and put a switch on it that will work fine. I am not sure how that will work if your IRCM is bad though. Good luck man. Keep posting, dont worry about the length, as long as its legit and in detail no one minds. The more detail of the problem the better chance on fixing it.

Kyle
 
Buck, I have been following this thread with interest as since i live in Phx. my temp guage sits on the "M" after 30 min or so (unless i'm on the freeway of course) I would like to rig a toggle for the low speed fan as you have suggested. When i have tried to chase down the details i usually see what you said " cut pin 14 and run a switch " is it that easy? If so can ya spare a detail or two?
Thanks
Jeff
 
if your check gauge is coming on for temp, you have more issues than a non working fan, because in this weather your fan shouldnt even come close to needing to come on... i have mine wired exactly like scotts with 197 tstat and lowspeed fan runnin 100% of the time, but even without the fan, my car would only get to like R after sitting for a LONG time, and then maybe it would need the fan, but never while driving it would it need the fan
 
yup

JSC, it is as easy as to cut and put a switch on. I personally dont have a switch, I just cut the wire so the fan is on all the time. Some do not reccommend this because it will burn the fan up sooner, but I dont care. I have a spare fan in the trunk at all times. When mine burns up ill wire the switch in. The way it works is, when there is no current going through the #14 wire the fan is on. When current is going through it the fan is off. That is why it turns on when you cut the wire. All you have to do is wire in a toggle switch. Just run the wire neatly through the engine bay, and through the firewall somewhere and into the cabin, then put the switch whereever you would like. Done. Good luck. And this will DEFINITELY lower your temps.

And for the original post to klsonesc, Pdennis is right. If the weather is as cold where you are as it is where i am then it should not be getting that hot period. The fan should still be coming on however. How hot does it get when you actually drive it, rather than idle. It is 20 degrees here, and my car is in the garage for the winter. Last time i started it I let it idle for a little more than an hour, and it never got over the N in norm. Thats becauset he fan is always on though. Maybe your radiator could be clogged, you can have it rodded at a radiator shop for around 50 bucks i hear. Keep checking things! your bound to find the problem soon now.
kyle
 
I am in southern california so the heat outside is a factor. I run around the "M" when driving. The IRCM has "Aug. 1997" stamped on it so it was recently replaced. Their is a section (about the size of a half dollar) of the radiator where the fins are bent like they were bumped into, could such a small restriction really cause the temp gauge to go into the red? And when the check gage light comes on, that is BECAUSE the temp gauge is up in the red, that is the whole point of a check gage light, to make you look at your gauge. Anyway, thanks for all the ideas, I will keep working on this.
 
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