Zfan1 Posted October 12, 2013 Share Posted October 12, 2013 I am having strange cooling issue and was wondering if anyone else has gone thru this. Driving around town it runs around 180 degrees, on the highway it runs around 190-200 into a head or cross wind. As soon as I drive down the highway with a tail wind the car heats up to 225 and eventually will overheat. Has anyone had similiar issues? I am running a L76/4L80E combo with 4 core Griffin radiator/Ford Taurus fan on high, fan comes on at 180 and shuts off at 170. Was wondering if I have a turbulance issue, trans cooler and cone air filter are out in front of the radiator which can effect airflow but why only with a tail wind. I am looking at blocking all circular vents on the radiator core support and sealing up around the radiator core support to force more air thru the radiator to see if that helps, kind of crazy, never was like this with my old set up. We took it to my buddies shop and made sure all the air in the system was evacuated, installed a new radiator cap (15 lb), not sure what to do next, maybe an air damn deflector or something to drive/guide more air into the radiator area. Thanks for any idea's or comments you might have. Mike Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted October 12, 2013 Share Posted October 12, 2013 What do you mean when you say: "it will eventually over-heat?" At what temp is your fan/fans coming on? Push or pull fan? How are you controlling fans? I have no idea about my temps-I need to get better gauges. My stock motor runs at the same grease pencil mark on the gauge as the old L24 did using a L24 sender unit. It looks on the poorly marked gauge like 220, but wfritts plugged his real-time OBD kit into the plug and said the temp was only 205. Quote Link to comment Share on other sites More sharing options...
Domzs Posted October 12, 2013 Share Posted October 12, 2013 Check your fan . Make sure it pulls or pushes ( pusher ) air toward the engine . I had a case like yours , the fan wires were hooked up wrong and it was pushing air ( puller setup ) . Your fan on/off is kinda low . What T-stat temp are you running ? Quote Link to comment Share on other sites More sharing options...
Kevin.pk Posted October 12, 2013 Share Posted October 12, 2013 (edited) Never had issue like that and have a similar cooling setup with a ls1/t56. afco radiator with taurus fan.jtr air filter setup in front of radiator. No trans cooler. No holes in core support filled in. I never get above 215. Taurus fan controlled by ecu or temp switch? Believe Stock fan control setup turns off the fan at certain speed. Definitely odd issue. Edited October 12, 2013 by 280zcar Quote Link to comment Share on other sites More sharing options...
redneck1545 Posted October 13, 2013 Share Posted October 13, 2013 I don't think you should be concerning yourself with head/cross/tail winds as at highway speeds...or any speed above said wind, you are essentially negating that fact. Look elsewhere as in coolant flow. I had an issue on mine where I close looped the heater core right back into the block with no issues. I later added the heater core in normal configuration but with the coolant flow in the 'off' position on the valve on the inside of the car that flow shut off as its supposed to. However, I had previously blocked off the bypass on the water pump to better facilitate even cylinder cooling but had forgotten about that with this engine in this car. Long story short, the thermostat could not sense the temperature quick enough to open and allow coolant to flow. It would overheat in a matter of minutes with the heater and valve in the off position. But with the heat on, it never got above 190. Not saying you have the same issue but I just think you should look somewhere beyond the scope of airflow with regards to headwind vs tailwind. Quote Link to comment Share on other sites More sharing options...
ktm Posted October 13, 2013 Share Posted October 13, 2013 I have absolutely no cooling problems at all with my ls1. When driving on the freeway my temperatures are about 175 degrees, this is with a 160 degree thermostat. My Ford Taurus fan is set to come on at 200 degrees and shut off of 195 degrees. I've wire up the second speed to a manual switch. Quote Link to comment Share on other sites More sharing options...
Zfan1 Posted October 13, 2013 Author Share Posted October 13, 2013 Well, I moved the large cone filter away from the front of the radiator and also found the the new radiator cap was not sealing, replaced it and drove it around last night. It ran 180-195 on the highway and 165-180 around town. Hopefully fixed the issue. The Taurus fan is wired on high thru the ecm and comes on at 180 and shuts off at 170, I am running a 160 thermostat. I am going to seal around the radiator and core support as I have a gap of around 1" on either side of the radiator that is open and see if that helps force more air thru the radiator. Quote Link to comment Share on other sites More sharing options...
ktm Posted October 14, 2013 Share Posted October 14, 2013 Sounds odd. Typically you run hotter around town and cooler on the freeway. Just today (75 degree ambient) my car never went above 175 degrees on the freeway. You should not have to wire your high speed in-lieu of your low speed. My low speed fan cools my car down fine. The ONLY time I actually manually turned on the high speed fan was when it was 108 degrees outside and I was stuck in traffic due to an accident. Are you 100% certain that you've eliminated all air out of your cooling system? Quote Link to comment Share on other sites More sharing options...
Miles Posted October 14, 2013 Share Posted October 14, 2013 I had the same problem and solved it with a Moroso water flow restrictor: http://www.jegs.com/i/Moroso/710/63440/10002/-1 Try the middle sized restrictor. Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted October 14, 2013 Share Posted October 14, 2013 The low speed output signal for the fan comes on at a lower temp than the high speed signal. If you wire the single fan to come on according to the low speed signal, your fan will start turning on and off according to the lower temp value. Quote Link to comment Share on other sites More sharing options...
ktm Posted October 15, 2013 Share Posted October 15, 2013 ....yes, but if he wires up the high speed switch on the fan to the low speed switch on the PCM, the high speed will turn on when the PCM is calling for the low speed. Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted October 15, 2013 Share Posted October 15, 2013 (edited) He only has 1 fan (a Taurus). The high-speed fan is a mis-nomer. It should be called the high-temp fan. It simply comes on if the first (low-speed/low-temp fan) fails to keep the motor cool; it just triggers at a higher temperature. I spent a ton of time on this searching ls1tech when I did my build. If running a single fan, it should go on the low-speed signal from the PCM/ECM and the high speed wire is not used. If using two fans, as I did, one wires one to the low-speed signal and the other to the high-speed signal. The fan may or may not even be the problem-it is easy enough to check, same as having the motors turning the fans the wrong way (mine were initially wired backwards). Could this equally be a timing or mixture problem? Has car been tuned yet? What's the latest ZFan? Edited October 15, 2013 by RebekahsZ Quote Link to comment Share on other sites More sharing options...
socorob Posted October 15, 2013 Share Posted October 15, 2013 With the Taurus fan and Volvo relay, you get 2 speeds with the single fan. The low speed grounds the low speed relay and the high speed grounds the high speed side of the relay. There is a wiring diagram I think I found it on LS1 tech for this setup. Quote Link to comment Share on other sites More sharing options...
ktm Posted October 16, 2013 Share Posted October 16, 2013 (edited) Keith, the Ford Taurus and Lincoln Mark VIII fans are dual speed fans with a single fan. There is a ton of information on the 'net as well as Hybridz/LS1tech about this (and the Lincoln Mark VIII) fan. With the Taurus fan and Volvo relay, you get 2 speeds with the single fan. The low speed grounds the low speed relay and the high speed grounds the high speed side of the relay. There is a wiring diagram I think I found it on LS1 tech for this setup. Exactly. Mike, your car really should not be overheating. I have a very similar setup: LS1/4L60E, cone filter protrudes from the side into the radiator area, and the trans cooler hangs down a little in front of the radiator. I know you said you and your buddy made sure you tested the system for air, but it could not hurt to check again. Have you checked the thermostat? Is it opening? It sounds like your fan is operating on high the entire time you are driving (both around town and at highway speeds). Just had a thought.....what about your lower radiator hose? I had a helluva time trying to source mine so I cobbled together an ugly frankenstein hose. Recently, got tired of looking at it and decided to replace it. Well, all of my replacements wound up severely kinking after one heating cycle. I went a slightly different route and used two 90ish elbows with a section of aluminum pipe. What is the condition of your lower hose? Edited October 16, 2013 by ktm Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted October 16, 2013 Share Posted October 16, 2013 I stand corrected. Quote Link to comment Share on other sites More sharing options...
Zfan1 Posted October 17, 2013 Author Share Posted October 17, 2013 (edited) I am going to check the thermostat this weekend, it's a first gen sbc 160 thermostat, reason is we used the straight neck billet water outlet in place of the traditional LS style that is mentioned on this site. The lower hose has not collapsed that I know of, the condition of the hose seems ok, maybe I need to install a spring though just for insurance. I do not know if you can control both fan speeds by ecm only, currently I have the hi speed hooked up but will switch it to the low speed and see what happens. We evcuated all the air from the cooling system at my buddies shop, they use a machine for that purpose. What would restricting water flow do to help keep the car cool on the highway, not sure I follow that one, sorry. We are going to redesign the fan shroud as well, the newer cars have flaps that allow air to move thru the radiator and shroud more efficiently. Edited October 17, 2013 by Zfan1 Quote Link to comment Share on other sites More sharing options...
RebekahsZ Posted October 17, 2013 Share Posted October 17, 2013 Thanks for the update. You may be making more power, but I just slapped my radiator in the car and ran it. It is an aluminum Champion eBay 3-row made to fit as a replacement for stock. I just have whatever thermostat was in it from the junkyard. Be sure to make sure your fan is pulling air into the engine compartment. The first time I wired mine-I had the power and ground backwards and it was pushing instead of pulling. Be sure to do simple stuff first. Quote Link to comment Share on other sites More sharing options...
PLATA Posted October 17, 2013 Share Posted October 17, 2013 (edited) I have absolutely no cooling problems at all with my ls1. When driving on the freeway my temperatures are about 175 degrees, this is with a 160 degree thermostat. My Ford Taurus fan is set to come on at 200 degrees and shut off of 195 degrees. I've wire up the second speed to a manual switch. My Z conversion had the old type rad which IMO look odd in that engine bay with the LS1 mill, I changed that with an Ebay aluminium rad with Camaro"s GM fans, NO ISSUES , I do have a second manual switch just in case Edited October 17, 2013 by PLATA Quote Link to comment Share on other sites More sharing options...
Zfan1 Posted October 17, 2013 Author Share Posted October 17, 2013 It's pulling for sure, moves a lot of air on hi speed. The radiator is a Griffin 24x19 aluminum radiator, nothing super fancy, been on the car for years. Quote Link to comment Share on other sites More sharing options...
socorob Posted October 17, 2013 Share Posted October 17, 2013 So it just started overheating? Maybe something is clogged? Steam vent ok? When I took my wife's car to get the timing belt changed there was a Toyota truck in there where a guy put the new radiator in and didn't take off the plug that was in the lower radiator port and it overheated and blew the head gasket. Quote Link to comment Share on other sites More sharing options...
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