LT1 Cooling System Questions
Thread Starter
Racer
Joined: May 2005
Posts: 497
Likes: 1
From: Casa Grande Az
LT1 Cooling System Questions
Yesterday while stuck in traffic, in phx the temp of the car crept close to 230 DEG! Now i've read that these LT1's run warm, but damn.... THATS warm. Now my question is when are the fans supposed to kick on? Cause once i noticed 228 deg i hit the ac button and kicked them both on and it cooled right down.
I am pretty sure its got a 195 deg tstat in it , cause cruzing down the road it will hold a rock steady 194-195.
Is it possible that I have a sensor that is bad? A relay perhaps?
Sorry to be
i tried doing a search for this cause i am sure its been talked about a million times , but the website kept throwing me a database error message.
Thanks in advance!
I am pretty sure its got a 195 deg tstat in it , cause cruzing down the road it will hold a rock steady 194-195.
Is it possible that I have a sensor that is bad? A relay perhaps?
Sorry to be
i tried doing a search for this cause i am sure its been talked about a million times , but the website kept throwing me a database error message.Thanks in advance!
Team Owner
Joined: Sep 2001
Posts: 62,157
Likes: 1,732
From: Athens AL
C7 of the Year - Unmodified Finalist 2021
C4 of Year Finalist (performance mods) 2019
Stock thermostat is 180. So if you believe yours is opening at 195, that needs replacement. Its going to hold a little warmer than stat temp though in normal driving because of its design.
Main fan comes on at 228F.
What you need to do is remove the radiator shroud and clean the debris between radiator and condensor, that will be clogged up. Dont halfazz it, you need to take the shroud off to get it all, so no spraying from underneath with the hose, you wont want to get the engine soaked that way anyway.
Only permanent fix is having the fans reprogrammed to come on sooner.
Main fan comes on at 228F.
What you need to do is remove the radiator shroud and clean the debris between radiator and condensor, that will be clogged up. Dont halfazz it, you need to take the shroud off to get it all, so no spraying from underneath with the hose, you wont want to get the engine soaked that way anyway.
Only permanent fix is having the fans reprogrammed to come on sooner.
Team Owner
Joined: Oct 2000
Posts: 96,443
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From: Fort Knox, KY
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You sure you don't have any FOB lodged in your radiator? C-4's are designed to suck the road like a Hoover vacuum cleaner and unfortunately, they'll scavenge nearly anything that gets in their path.
Check to see if you don't have any paper cups, leaves, feathers, etc.. jammed up in that ****.
Check to see if you don't have any paper cups, leaves, feathers, etc.. jammed up in that ****.
Racer
Joined: Apr 2005
Posts: 322
Likes: 0
From: Mt. Pleasant TX
No Problem probably
I just went through a weekend of fixing cooling issues . Sounds like you are probably okay. My fans kick on at 228° now but by the time they are on it will show 230-231° then the fans bring it back down to 217° . That's in traffic. On the highway I also run 190-194° w/ the stock 180° thermostat. I was running that anyway, I am noticing 188-192° now since replacing a "bad" relay and adding some "40 below" to the radiator. It seems to have brought the normal highway temps down by 5-6° . Hope this reassures you and that you do not actually have a problem.
Racer
Joined: Jan 2005
Posts: 418
Likes: 45
From: Houston Texas
Some other cars have 1 fan running & the 2nd fan coming on when needed (or forced on with the A/C). I have Honda that works that way. The LT-1 has 2 fans that run together; either BOTH at low speed or BOTH at high speed. Check "Rufneck" 's latest post about running hot. You'll see the crap he went thru because some Bubba put in the wrong parts.
Thread Starter
Racer
Joined: May 2005
Posts: 497
Likes: 1
From: Casa Grande Az
Wow guess i should'nt worry. I am just used to all my old smallblocks when 230 deg was really really bad.
I will however remove the shroud and make sure everything is clean in there, cause it was only 90 deg or so yesterday , soon its gonna be 110+
I will however remove the shroud and make sure everything is clean in there, cause it was only 90 deg or so yesterday , soon its gonna be 110+
Safety Car
Joined: Feb 1999
Posts: 3,504
Likes: 4
From: Mexico Beach FL
First, and foremost, the LT1/LT4 have a "reverse flow" cooling system, and it shouldn't be directly compared to a standard flow system.
With a 180 degree thermostat, it will normally give you about 194 degrees (digital readout) on the highway with lots of air flow over the radiator. A 160 degree thermostat will give you about 178 - 180 degrees under the same circumstances.
The thermostat in the LT1/LT4 control the temperature of the coolant "entering" the engine (assuming sufficient air flow) instead of "exiting" the engine like a standard flow system does.
So, with 180 degee coolant entering the engine and picking up 14 degrees from the engine, the coolant on exit from the engine (where the coolant temperature sensor is) will be 194 degrees.
On a '92, the stock setting of the primary fan to come on is about 221* and the secondary about 234*.
Tom Piper
With a 180 degree thermostat, it will normally give you about 194 degrees (digital readout) on the highway with lots of air flow over the radiator. A 160 degree thermostat will give you about 178 - 180 degrees under the same circumstances.
The thermostat in the LT1/LT4 control the temperature of the coolant "entering" the engine (assuming sufficient air flow) instead of "exiting" the engine like a standard flow system does.
So, with 180 degee coolant entering the engine and picking up 14 degrees from the engine, the coolant on exit from the engine (where the coolant temperature sensor is) will be 194 degrees.
On a '92, the stock setting of the primary fan to come on is about 221* and the secondary about 234*.
Tom Piper
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