View Full Version : Still Running HOT!
SinisterZ28 Mar 12th, 01, 11:18 AM I own a 96 Z28. It has a 5.7 liter 350. Ever since I flushed out the cooling system and put in new Dexcool, the car runs at about 220-230. I put in a 160 degree thermo and flushed the system again. I even installed a third fan in front of the radiator, hooked them all up together with an adjustable thermostatic switch, and had the radiator taken apart and cleaned professionally. All the fans come on at the temp I choose and the temp stays at about 200. If I get on it a little or hit a light, it will start creeping up. I installed 4.10 gears, TPS enhancer, 34% underdrive pulleys, 3" exhaust, K&N cold air, and 2" drop. The car has 56,000 miles, its a 6-speed, no service engine light. The low coolant light comes on after a few minutes of driving. I took it the dealer and they said the coolant was full. New Radiator?? Help!
DjD Mar 12th, 01, 04:08 PM Why the 3rd fan? What did it run at before you flushed the system? I would question the 3rd fan in front, first it blocks the radiator some and second if it isn't a pusher type fan it's actually fighting the factory fans. The guy that cleaned your core should have made a pitch to sell you a new one if it was needed so put that on the back burner.
I'm a little confused because you say the fans come on when you want them to and the temp stays about 200. Then you say it goes up if you sit at a light! Another confusing issue is you added an adjustable thermostat switch. What happened to the computer controlled switch built into the car that you are susposed to reprogram when you put the 160 stat in?
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...Dennis
'69 RS Convertible w/SS trim (http://www.camaroslimited.com/memberscars/den.htm)
'96 Z28SS #1679 of 2410 (http://www.camaroslimited.com/graphics/memcars/96ss.jpg)
"The Club" (http://camaroslimited.com)
ScottB Mar 12th, 01, 06:35 PM The computer needs a 195 thermostat for the smog equip. to operate properly. A 160 thermostat will cause problems. 200 is normal and 220 or 230 is not unusual for that car.
BIGDOG454 Mar 13th, 01, 02:03 PM Maybe the underdrive pulley is causing the waterpump to spin a little too slow.
I'm not positive about Dexcool, but regular anti-freeze is less heat conductive (carries less BTUs) than water. If that is the same case with Dexcool, then your best off making the mixture as with as much distilled water as possible rather than heavy on the coolant.
BillK Mar 13th, 01, 05:04 PM Z,
1. Are you certain that the car is running at 220 or is that just what the gauge says ? I know that sounds stupid, but gauge senders do go bad and you could be getting a false reading.
2. The Low Coolant sensors are also known to go bad.
3. Like everyone else said, what temp did the car run at before the change, I am pretty sure the stock fan setup does not even turn on until 220.
You need to find a good shop with an Infrared temp gun and a scanner to verify the actual operating temperature. The stock fan setup should be more than enough to keep the car cool.
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Bill Koustenis
Owner
Advanced Automotive Machine
Waldorf Md
1971 Chevelle "Heavy Chevy" original owner
1973 Z-28 ..one family car...Brother bought it new in 73
bowtieusa Mar 14th, 01, 04:33 PM Don't overlook your radiator cap. If you go too low a pressure, you change your boiling point of the coolant drastically. I found out the hard way. I spent a lot of time and money to realize my simple small problem was a cheap 7lb. radiator cap, when I needed a 13 or greater.
Good luck!
SinisterZ28 Mar 19th, 01, 09:03 AM Thanx for the replies guys. The third fan I installed is wired as a pusher. I've replaced the temperature sending unit thats located on the water pump. I've also replaced the temperature sensor thats located on the drivers side of the block. The water pump is internally gear driven and not driven by the serpentine. The temp used to always linger at 210, and never go above. Before the pusher fan was installed, after shutdown the coolant would boil over. I went with an adjustable switch because of low funds. The dealership, or anywhere else I went makes any other thermo other than a 180 for that car. For some reason right after I flushed the system the fans would come on at the right temp, but wouldn't keep the temp from climbing unless I was on the highway. If I let the car idle and the temp would reach 250-260, BOTH fans would kick on spinning at a much higher RPM than usual. This would begin to bring down the temp slighly. I would shut down before I could see if it was gonna keep going down. I've tried the radiator cap, didn't work. I appreciate the replies, please keep them coming because summer is going to get me!
KingCobra5000 Mar 19th, 01, 09:36 AM Hey Bro! Why don't you get some Water Wetter?
KingCobra5000 Mar 19th, 01, 09:39 AM Yes.....ladies and gentlemen....boys and girls! CHILDREN OF ALL AGES! I drive a COBRA...I still luv Camaros!
DjD Mar 19th, 01, 10:40 AM Water wetter will make the fluid in the system disapate heat a little better. Kinda like running 30/70 antifreeze to water instead of 50/50. If there is a system problem (sounds like it to me) it won't help.
I think your car's computer is competing with the thermo switch you installed and your fans are confused as to what they are susposed to do! Disconnect the add on thermo switch and put the old stat back in and see what happens.
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...Dennis
'69 RS Convertible w/SS trim (http://www.camaroslimited.com/memberscars/den.htm)
'96 Z28SS #1679 of 2410 (http://www.camaroslimited.com/graphics/memcars/96ss.jpg)
"The Club" (http://camaroslimited.com)
SinisterZ28 Mar 19th, 01, 11:57 AM Before I put in the third fan and switch, I put the 180 thermo back in and dis and reconnected the battery. I cycled the ignition switch, and nothing. Ran even hotter, faster. It runs good now with the third fan, thermo switch, and 160 theromstat, but even with all that in place it will still get up to approx. 235-240 after I get on it on a hot day. Once above 185, power loss is noticeable.
oger Mar 19th, 01, 02:45 PM Underdrive pulleys are a great idea except everyone I know took them off for the same problem you are having. The waterpump just doesn't turn fast enough under load.
jamesbern Mar 19th, 01, 04:30 PM Does your car have an automatic tranny? If it does check it out, I had a heating problem that was caused by my transmission once.
RAMAIRTA18 Mar 20th, 01, 08:00 PM dude dont worry about it i have a 96 ws6 ta and have a 160 stat it does the same thing. its programmed into your computer to release when the fans come on so go invest in a hypertech prog. and itll solve all your problems. plus did you redo your computer for the gears???? itll help a little
your speedo will be a little off
Ryslam Mar 23rd, 01, 10:02 AM I have a 96 SS, and it runs pretty hot too...Especially when it idles..Sometimes it'll creep really close to the red unsafe zone, and I worry it will overheat..But it never does..When I'm driving, the temp. gauge is usually right on the middle..
tom billings Mar 23rd, 01, 04:50 PM do you have an air pocket stuck in the cooling system? i usually find that if the system is not bled completely, the low coolant light will come on after a few miles of driving. also, is your gauge accurate? is there an air dam under the front facia, is any 'duct work' around the radiator missing? just some other things to check, did you flush the heater core as well? dex-cool leaves some nasty stuff in your cooling system, make sure you get it all out, s-10 blazers are notorious for problems in the system due to this coolant. gm has a four hour flush proceedure to clean out the system, may need to check that out too. hope this helps out.
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71 camaro ss 66 chevelle 396/4spd www.americaniron.net (http://www.americaniron.net)
algenard Mar 24th, 01, 03:06 PM <BLOCKQUOTE>quote:</font><HR>Originally posted by SinisterZ28:
I own a 96 Z28. It has a 5.7 liter 350. Ever since I flushed out the cooling system and put in new Dexcool, the car runs at about 220-230. I put in a 160 degree thermo and flushed the system again. I even installed a third fan in front of the radiator, hooked them all up together with an adjustable thermostatic switch, and had the radiator taken apart and cleaned professionally. All the fans come on at the temp I choose and the temp stays at about 200. If I get on it a little or hit a light, it will start creeping up. I installed 4.10 gears, TPS enhancer, 34% underdrive pulleys, 3" exhaust, K&N cold air, and 2" drop. The car has 56,000 miles, its a 6-speed, no service engine light. The low coolant light comes on after a few minutes of driving. I took it the dealer and they said the coolant was full. New Radiator?? Help!<HR></BLOCKQUOTE>
I don't know if this is any help, but I had a similar problem after dropping a new 350 into my '67 Firebird. Replaced the radiator, checked everthing imaginable and discovered my radiater fan motor wires were crossed. The motor, running the wrong way was pushing instaed of pulling air through the radiator. The engine runs at a cool 200 degrees consistantly now.
Al
Mr Bowtie Apr 1st, 01, 07:24 PM It is not unusual for a Camaro to run from 220-230. My Camaro runs at 220 while sitting at a light. I don't think the 3rd fan was a good idea though..... And if I were you, I'd drive it out for a bit, then take it home and sit in the yard on a really sunny day and let it idle. See how far the temp gauge will go. If it goes up and bumps redline, then you know it is overheating. As of what you have said so far, it sounds normal to me.
Mark W. Winning Apr 2nd, 01, 04:34 AM The 4th gens are real easy to get air bound also. If you don't get all the air "burped" out, after you changed fluids, you can have problems.
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Mark
1992 Firebird 355/Six Speed (Soon to be LT1)
1991 RS 350 / 700-R4
1987 Toyota Pickup 383 / 500 + HP 10.963 @ 119.95 Slicks / 11.997 @ 114.23 Radials
"Speed KILLS, so drive a FORD and live forever!"
http://personal.lig.bellsouth.net/~racer383/
Member of the "unwanted" 3rd Gen group.
My stock '96 Z28SS doesn't run above 210 on a hot day. I'm using the factory guage and with the spread between 160 on the low side and 260 on the high side, 210 is smack in the middle of the guage. I have never tested the accuracy of the guage so I don't know true temps....
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...Dennis
'69 RS Convertible w/SS trim (http://www.camaroslimited.com/memberscars/den.htm)
'96 Z28SS #1679 of 2410 (http://www.camaroslimited.com/graphics/memcars/96ss.jpg)
"The Club" (http://camaroslimited.com)
mahan67RS Apr 2nd, 01, 07:37 AM I agree with tom billings and Mark Winning. It sounds to me like you have an air pocket in the engine. One way to try and get rid of it is to pull the car up on some ramps. Remove the radiator cap and run the engine for a couple of minutes. Every newer car I have owned I have had to do this. Water wetter would help also but you should locate the problem first.
ilbl8 Apr 2nd, 01, 11:49 AM if i reacall the LS1 motor's used on this year camaro have a specific way of burping the motor. on the therm housing there is a cap or a bleed port to remove air from the system. check in a repair maual about this. cause doing it the old way will not work as the motor's are a reverce flow system. the cooling water go's to the head's first then the block then the radiator there is no coolant in the intake on this motor, they also use a therm that conrol's both the inlet flow and out let flow. it will also bypass the out let and inlet and keep the coolant going just around inside the motor. not the way gen1 work's, it go's to the block then the head's and intake then the radiator. the therm only controles the out let flow on a gen1.
[This message has been edited by ilbl8 (edited 04-02-2001).]
KingCobra5000 Apr 6th, 01, 07:53 AM All u have to do is drive it so freakin fast, it don't get a chance to get hot!
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