93 LT1 Running Hot, wrong coolant perhaps?
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93 LT1 Running Hot, wrong coolant perhaps?
I just bought a 93 LT1 and it is running hot. 240 degrees on a hot day in downtown traffic. I notice the anti-freeze is the green stuff and my CHilton's manual specifies the Dexcon (orange) for the P series engines. Could this be the cause of the high temps I'm seeing?
Instructor
Joined: Jun 2000
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From: Chicago
It could be or it could not be. If the green was mixed with the orange at some point you could have clogs developing, they don't mix well. Since it is green now, I would go for a flush and try new green at this point.
First though, make sure your fans are coming on as specified as well, these cars run hot but 240 is too high. I run 190-195 in normal temps. If it is say above 80-85F out and stop and go, I can hit 215. Though my fans are programmed to come on lower with my 160 degree thermostat.
There are a gazillion previous threads if you search.
First though, make sure your fans are coming on as specified as well, these cars run hot but 240 is too high. I run 190-195 in normal temps. If it is say above 80-85F out and stop and go, I can hit 215. Though my fans are programmed to come on lower with my 160 degree thermostat.
There are a gazillion previous threads if you search.
Race Director
Joined: Oct 2005
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From: Rolla Missouri
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Your '93 came with the "green" stuff from the factory, so I wouldn't change types if I were in your position.
That Chilton's manual is probably better than nothing, but they try group all C4's together.
Not that it matters here, but I believe only the '96 shipped with DexCool coolant.
And that is what I continue to use in mine.
The temps you posted, although are a little high are not completely unheard of sitting in downtown traffic.
Hint: Turn on the A/C, which will force the cooling fans on. The car will run cooler with the A/C on.
Next step, is to make sure your cooling system is in good shape. A good flush/cleaning and will do wonders.
Also make sure there is no trash lodged up the radiator fins. Lay on your back and look up under the nose and you'll see whey these cars are "vacuum cleaners".
That Chilton's manual is probably better than nothing, but they try group all C4's together.
Not that it matters here, but I believe only the '96 shipped with DexCool coolant.
And that is what I continue to use in mine.
The temps you posted, although are a little high are not completely unheard of sitting in downtown traffic.
Hint: Turn on the A/C, which will force the cooling fans on. The car will run cooler with the A/C on.
Next step, is to make sure your cooling system is in good shape. A good flush/cleaning and will do wonders.
Also make sure there is no trash lodged up the radiator fins. Lay on your back and look up under the nose and you'll see whey these cars are "vacuum cleaners".
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I'm going to try a flush this week as well as a new thermostat. I cleaned some debris off the radiator a week or so ago. I also bled some air out of the cooling system but I realize I need to get the car running/hot to get a burp of the system (I purged some air out the blled valve but the motor was not running) . There may still be some air in the system. Many thanks!
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Le Mans Master
Joined: Jul 2005
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The cooling system is pretty simple..except for the system that turns on the fans..not sure about that..but if you want to clean it out totaly you need to remove the knock sensors..that is the low point of the system where all the gunk accumulates..its a PITA but the only way to drain the whole system..the FSM has a section on flushing and refilling the system..everyone needs the factory manual to work on these cars..chiltons is..almost useless...
Le Mans Master
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From: Clearwater Florida
..................... The chiltons didn't even make a good wheel chock ... its in the throne room ...............
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AH Ha! excellent advice... and greatly appreciated. I'm glad you mentioned that about having to reprogram the fans, also can't wait to get myhands on some 2inch PVC and a FSM.
Also the import of removing the knock sensors. Thanks to all you guys!
Also the import of removing the knock sensors. Thanks to all you guys!
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re: knock sensors, I can believe it. The engine was supposedly overhauled 18k miles ago so maybe they won't be to frozen in place... We'll see. I ran the car this morning and drained some more air out of the cooling system but I can see it is still getting up to 230 degrees in just a short trip to town. I'm going to try the flush and new stat, pressure test the system maybe. It cools down at highway speeds (208-215) then warms back up to what appears to be the limit when you slow down in city traffic. I'll feel better when I get this fixed. This is my Daily Driver and since we are near 100 degrees everyday, just a matter of time before a head gasket or something else blows up. Thanks guys!
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re: knock sensors, I can believe it. The engine was supposedly overhauled 18k miles ago so maybe they won't be to frozen in place... We'll see. I ran the car this morning and drained some more air out of the cooling system but I can see it is still getting up to 230 degrees in just a short trip to town. I'm going to try the flush and new stat, pressure test the system maybe. It cools down at highway speeds (208-215) then warms back up to what appears to be the limit when you slow down in city traffic. I'll feel better when I get this fixed. This is my Daily Driver and since we are near 100 degrees everyday, just a matter of time before a head gasket or something else blows up. Thanks guys!
hope this helped!
Burning Brakes
Joined: Aug 2003
Posts: 944
Likes: 0
From: Mesa Az
Your '93 came with the "green" stuff from the factory, so I wouldn't change types if I were in your position.
That Chilton's manual is probably better than nothing, but they try group all C4's together.
Not that it matters here, but I believe only the '96 shipped with DexCool coolant.
And that is what I continue to use in mine.
The temps you posted, although are a little high are not completely unheard of sitting in downtown traffic.
Hint: Turn on the A/C, which will force the cooling fans on. The car will run cooler with the A/C on.
Next step, is to make sure your cooling system is in good shape. A good flush/cleaning and will do wonders.
Also make sure there is no trash lodged up the radiator fins. Lay on your back and look up under the nose and you'll see whey these cars are "vacuum cleaners".
That Chilton's manual is probably better than nothing, but they try group all C4's together.
Not that it matters here, but I believe only the '96 shipped with DexCool coolant.
And that is what I continue to use in mine.
The temps you posted, although are a little high are not completely unheard of sitting in downtown traffic.
Hint: Turn on the A/C, which will force the cooling fans on. The car will run cooler with the A/C on.
Next step, is to make sure your cooling system is in good shape. A good flush/cleaning and will do wonders.
Also make sure there is no trash lodged up the radiator fins. Lay on your back and look up under the nose and you'll see whey these cars are "vacuum cleaners".
Burning Brakes
Joined: Aug 2003
Posts: 944
Likes: 0
From: Mesa Az
re: knock sensors, I can believe it. The engine was supposedly overhauled 18k miles ago so maybe they won't be to frozen in place... We'll see. I ran the car this morning and drained some more air out of the cooling system but I can see it is still getting up to 230 degrees in just a short trip to town. I'm going to try the flush and new stat, pressure test the system maybe. It cools down at highway speeds (208-215) then warms back up to what appears to be the limit when you slow down in city traffic. I'll feel better when I get this fixed. This is my Daily Driver and since we are near 100 degrees everyday, just a matter of time before a head gasket or something else blows up. Thanks guys!
now I am almost tempted to run something like water-wetter just to try it and see how it works.
Melting Slicks
Joined: Aug 2008
Posts: 2,082
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From: Palmdale CA
Been there and done it!
Start with the radiator, this seems to be the week link in our cooling systems do to debri being injested through the bottom of the car...(bottom feeder)
Your temps are getting kind of warm in my opinion, I see 185-190 highway, and 188-210 city with the A/C running. Out side temps 90-105
I'm guessing your coolent was "green" since the overhaul, and it's probably not worth pulling the Knock sensors...your call.
good luck,
Start with the radiator, this seems to be the week link in our cooling systems do to debri being injested through the bottom of the car...(bottom feeder)
Your temps are getting kind of warm in my opinion, I see 185-190 highway, and 188-210 city with the A/C running. Out side temps 90-105
I'm guessing your coolent was "green" since the overhaul, and it's probably not worth pulling the Knock sensors...your call.
good luck,
