Supra Forums banner
1 - 20 of 39 Posts

· Registered
Joined
·
311 Posts
Discussion Starter · #1 ·
first off i just want to say I have electric fans on the car but they are not running at all... You probably all will say its my fans causing the problem but I am making sure cause I have a feeling its not. The reason why I feel its not from the fans is because the cooling system is pressurized and cannot boil am i right? if there was an air pocket in there it could boil? I Did the headgasket abuot a month ago, ever since then It seams there is a bubble I just cant get out of my system. I tried today on a slanted street and left my rad cap off for 30 minutes running, put it back on went for a cruise and my gauge goes up not up to red but up higher then what it should be and coolant was boiling, i can feel it thru the upper rad hose. I have no coolant leaks, every morning i check my rad and its filled to the rim. So no dissapearing coolant. As I said my fans are not working so I dont drive the car hard and its maybe 15-20 minute drives tops.
 

· Banned
Joined
·
5,915 Posts
How about installing the factory clutch fan and find out of you still have the problem.

Does your car have a thermostat?
 

· 7m love... dont hate.
Joined
·
2,728 Posts
first off i just want to say I have electric fans on the car but they are not running at all... .
you do realize that stock fans run all the time. water boils at 212* each psi the rad cap is set to that increases the boiling point of water. when you go past that point you coolant starts to boil and evaporate. if you think running your car with no fans is fine who knows how your hg job was sorry.
 

· Registered
Joined
·
6,381 Posts
Change your radiator cap. You are ptobabaly seeing the boiling going on in the reservoir.....and a bad radiator cap can cause that. ...but yeah...if your car is idling when you checking this..make sure the fans work because there is no air flow (like when driving) across the radiator to cool it.
 

· Frozen Lake Driver
Joined
·
1,402 Posts
the electric fans i installed work incredibly well over the stock clutch fan. if your fans aren't working trying connecting them to the same spot where the AC condenser fans were connected to. I've had that problem with a few vehicles i've owned where the coolant becomes too warm in the system so it flows into the overflow and then boils in the overflow tank.
Fix those fans!
you would have been better off trying to fix those fans first to see if that would solve the problem instead of everyone on here telling you that what you think is the problem is the problem
good luck
 

· BOOST IS BETTER!!
Joined
·
181 Posts
if your fans aren't working trying connecting them to the same spot where the AC condenser fans were connected to.
Bad idea. A/C Fans kick on at 230*. Not good. Wire it to your ignition so they run all the time.
 

· Registered
Joined
·
14,778 Posts
you do realize that stock fans run all the time. water boils at 212* each psi the rad cap is set to that increases the boiling point of water. when you go past that point you coolant starts to boil and evaporate. if you think running your car with no fans is fine who knows how your hg job was sorry.
water does boil at 212.. but 50/50 antifreeze wont boil at 212. its probably quite a bit higher than that.


you NEED fans on your car, wether you like it or not. running all the time.

the only variable that changes to keep your car the right temp is the thermostat.

and if you have a bubble you cant get rid of. you need to do a leakdown test, or a combustion gas test and see if your blowing air into your coolant passages because of a bad HG job.

do the tests first, and if those dont asnwer your question, then come back and post again with new info. other than that

1. fans run all the time
2. check thermostat/change it
3.make sure you have 50/50 coolant antifreeze
4. do a leakdown test or a combustion gas test (little vial attaches to the rad cap, and allows air inside, water inside changes color if combustion gasses are present, easy to tell if you have a blown HG)
 

· Registered
Joined
·
171 Posts
this is full of FAIL, stock gauge is horrible to use for accuracy.
Mine doesnt move until over 220 degrees, if yours is above the half way mark its a bit hotter then that!

No fans? seriously why? again the stock gauge is only going to move and let you know things are hot as hell, not enough accuracy to let you know its a "little" hotter then normal.
and DO NOT hook them up to the ac or auxiliary fan circuit. That relay is ment for 20 amps or less.
 

· Registered
Joined
·
14,778 Posts
let me just say again about this, that if you have a small pinhole size leak, just putting a small amount of air into your system. your coolant WILL NOT FLOW nearly as good as an airless system under compression.... coolant that isnt flowing at the proper speed (either too slow or too fast) will cause overheating as well.. so you thermostat could be fine, but if you have air in the system it will overheat no matter what you do.
 

· (◕_◕)
Joined
·
8,453 Posts
What would be a good temp to set my electric fans thermostat to turn on at?
 

· Registered
Joined
·
311 Posts
Discussion Starter · #15 · (Edited)
sup guys.. thanks for you opinions. I'm pretty sure its the rad cap.. I swaped the caps off my parts supra and no bubbles. I'm still gonna flush the rad, change thermostat and buy a brand new rad cap.
Anyway took off the flex-a-lite fans and I am curious if these were installed correctly.. The fans sit on the inside of the rad engine bay side, held in with these plastic screws that went directly thru my radiator fins and into a a plastic threaded peice. Im curious if thats the correct way to install them?? I suppose the resiviour in the rad is not as big as the whole radiator assembly?? because none of them are leaking coolant.. I hope the P.O didnt fuck the rad up.
 

· VVT-i FTW
Joined
·
704 Posts
Hopefully it was your radiator cap, because when my coolant started randomly dissapearing and boiling, it was my headgasket, even after I changed it, turns out there was corrosion on the block between the cooling channels and the cylinder walls. Have you checked your oil lately?
 

· Registered
Joined
·
6,381 Posts
bought a brand spanking new rad cap and put the stock mechanical fans back on.. my car did not even hit operating temp on the way to work this monring. I guess it was the rad cap.
Radiator caps are the least looked at / changed items on the SUpra. Problem is, as soon as someone says the word "overheating" everyone wants to jump to the conclusion that its your head gasket or the fans....electric fans work fine if they are the right size/capacity for your car and are hooked up properly with all safety devices( relays/heavy wire gauge etc) in place.
 

· Registered
Joined
·
311 Posts
Discussion Starter · #20 ·
no matter what if you post a thread with overheating they think its a BHG.. lol one guy on this thread told me to do a leakdown test, compression check haha. I'm not mocking the idea of that just that becuase I decided to drive with no fans he assumes I did a poor HG job.. Im confident with my mechanical skills.
 
1 - 20 of 39 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top