LT1-LT4 Modifications 1993-97 Gen II Small Block V8

overheating problem

Thread Tools
 
Search this Thread
 
Old Feb 13, 2010 | 01:40 PM
  #1  
scj's Avatar
scj
Thread Starter
TECH Addict
iTrader: (89)
 
Joined: Feb 2008
Posts: 1,738
Likes: 23
Question overheating problem

okay, so my car has been overheating and i cannot figure it out.

the car has new rad hoses, a new heater core, new heater core lines, new thermostat, new coolant, and I've bleed and bleed the system of air and the coolant is full, the fans seem to kick on intermediately, sometimes, but not always, I've replaced the relays for them as well. it's like 30 degrees outside so the car shouldn't even get about 190 degrees while cruising, but it'll get up to 210 after about 15-20mins of cruising 55mph, and then stay there, if i give it gas while it's in gear to accelerate the car quickly overheats, if i throw it in neutral and let off the gas the car will quickly cool off, and it'll continue to do the same thing if i try and accelerate any. yet if i'm sitting at idle and i give it gas it will cool off a little, then after a few mins it will overheat.

wtf idk what to do.

help please
Reply
Old Feb 13, 2010 | 01:58 PM
  #2  
the_merv's Avatar
Banned
iTrader: (88)
 
Joined: Mar 2006
Posts: 21,019
Likes: 891
From: The Beach...
Default

What is your mixture %..
Reply
Old Feb 13, 2010 | 02:37 PM
  #3  
SS RRR's Avatar
Village Troll
20 Year Member
Liked
Loved
Community Favorite
iTrader: (2)
 
Joined: Oct 2002
Posts: 11,111
Likes: 596
From: Jackstandican
Default

Originally Posted by scj
the fans seem to kick on intermediately, sometimes, but not always,
When exactly do they kick on? Are you saying they don't come on when they're supposed to? Best thing to do is get ahold of some scanning software to see if your PCM is reading coolant temperature correctly.
Do you have the radiator/air deflector in place?
Reply
Old Feb 13, 2010 | 02:54 PM
  #4  
scj's Avatar
scj
Thread Starter
TECH Addict
iTrader: (89)
 
Joined: Feb 2008
Posts: 1,738
Likes: 23
Default

Originally Posted by the_merv
What is your mixture %..
i have no idea, prolly about 30% but since it's been overheating often and i've been having to drain it and refill it i haven't filled it with 50% coolant because i'm tired of having to drain it and buy new coolant.
Originally Posted by SS RRR
When exactly do they kick on? Are you saying they don't come on when they're supposed to? Best thing to do is get ahold of some scanning software to see if your PCM is reading coolant temperature correctly.
Do you have the radiator/air deflector in place?

yes i have the air deflector in place. idk when or if they kick on or not, the only way to tell is if the car is on jack-stands and feeling them come on from underneath, and last time i had it on jack-stands they were coming on, but it'll get hot and nothing seems to be kicking on, like it'll get around 220 and it keeps getting hot like nothing's holding it back, and i can't hear the fans whenever they're on or not over the motor running.
Reply
Old Feb 13, 2010 | 03:33 PM
  #5  
SS RRR's Avatar
Village Troll
20 Year Member
Liked
Loved
Community Favorite
iTrader: (2)
 
Joined: Oct 2002
Posts: 11,111
Likes: 596
From: Jackstandican
Default

Originally Posted by scj
i have no idea, prolly about 30% but since it's been overheating often and i've been having to drain it and refill it i haven't filled it with 50% coolant because i'm tired of having to drain it and buy new coolant.
Your coolant mixture has nothing to do with what is happening.
yes i have the air deflector in place. idk when or if they kick on or not, the only way to tell is if the car is on jack-stands and feeling them come on from underneath, and last time i had it on jack-stands they were coming on, but it'll get hot and nothing seems to be kicking on, like it'll get around 220 and it keeps getting hot like nothing's holding it back, and i can't hear the fans whenever they're on or not over the motor running.
Is it because the engine is loud? Reason I ask is you have a two speed system and when the fans engage to high they can usually be heard. Almost reads like your fans are only engaging at low speed. Dunno... I have to ask, but are you sure your hoses are all correctly in place?
Reply
Old Feb 13, 2010 | 03:50 PM
  #6  
95TransAm_ToM's Avatar
Launching!
 
Joined: Nov 2007
Posts: 203
Likes: 0
From: Eastern, CT
Default

you said you changed everything...but did you change your two temp sensors??? One on the DS block and the other on water pump
Reply
Old Feb 13, 2010 | 04:24 PM
  #7  
RamAir95TA's Avatar
TECH Senior Member
iTrader: (2)
 
Joined: May 2005
Posts: 9,467
Likes: 8
From: South Jersey
Default

If you don't have any aftermarket PCM programming (per your sig), your temps are fine. "Overheating" is defined as getting into and past the red. These cars are made to operate around 200 - 235 degrees (default fans kick on at 227 and 235 degrees for low and high).
Reply
Old Feb 13, 2010 | 06:29 PM
  #8  
93TAJ.C.'s Avatar
TECH Resident
iTrader: (1)
 
Joined: Oct 2008
Posts: 836
Likes: 0
Default

It sounds like its running fine to me. The fans shut off over 55 dont they? Is that why you said intermittant.
Reply
Old Feb 14, 2010 | 04:20 AM
  #9  
the_merv's Avatar
Banned
iTrader: (88)
 
Joined: Mar 2006
Posts: 21,019
Likes: 891
From: The Beach...
Default

Originally Posted by SS RRR
Your coolant mixture has nothing to do with what is happening.
Not necessarily.

If he has too much actual 100% Glycol instead of the 50/50 that you can buy, then his car will do exactly what he is describing..I've seen it happen plenty of times.
Reply
Old Feb 14, 2010 | 08:52 AM
  #10  
scj's Avatar
scj
Thread Starter
TECH Addict
iTrader: (89)
 
Joined: Feb 2008
Posts: 1,738
Likes: 23
Default

the car does get into the red

everything is installed correctly
Reply
Old Feb 14, 2010 | 11:41 AM
  #11  
trippinholyman's Avatar
Launching!
 
Joined: Feb 2009
Posts: 280
Likes: 0
From: bodymore
Default

Originally Posted by 95TransAm_ToM
you said you changed everything...but did you change your two temp sensors??? One on the DS block and the other on water pump

Seconded, water pump temp sensor goes to the PCM, driver side head the gauge on the dash. A lot of people forget the temp sensors. My fans were cutting on late a few weeks ago and my car was overheating and it was mostly because of the thermostat and the water pump temp sensor.

Sounds like your car is running fine. Idling in traffic it can get up to 230, but fans will kick on and bring it back down. Cruising at 55 and the gauge in the middle (190-210ish) is normal.

Check your temp sensors.

Last edited by trippinholyman; Feb 14, 2010 at 12:03 PM.
Reply
Old Feb 14, 2010 | 02:52 PM
  #12  
SS RRR's Avatar
Village Troll
20 Year Member
Liked
Loved
Community Favorite
iTrader: (2)
 
Joined: Oct 2002
Posts: 11,111
Likes: 596
From: Jackstandican
Default

When you say new coolant was used did you replace everything in the cooling system? Did you keep track as to how many quarts you used in your mix? The LT1 cooling system has an approximate 15qt capacity. Did you do all of this because there was a problem initially or was the car fine and then started overheating after all of these things were replaced? Where did you get the thermostat? Are you sure it is LT1 specific?
Reply
Old Feb 14, 2010 | 04:33 PM
  #13  
scj's Avatar
scj
Thread Starter
TECH Addict
iTrader: (89)
 
Joined: Feb 2008
Posts: 1,738
Likes: 23
Default

Originally Posted by trippinholyman
Seconded, water pump temp sensor goes to the PCM, driver side head the gauge on the dash. A lot of people forget the temp sensors. My fans were cutting on late a few weeks ago and my car was overheating and it was mostly because of the thermostat and the water pump temp sensor.

Sounds like your car is running fine. Idling in traffic it can get up to 230, but fans will kick on and bring it back down. Cruising at 55 and the gauge in the middle (190-210ish) is normal.

Check your temp sensors.
the water pump temp sensor is new, head one idk about. the fans don't kick on though i'm sure because it goes well over 230 all the way into the read, and doesn't begin to cool off at all.

Originally Posted by SS RRR
When you say new coolant was used did you replace everything in the cooling system? Did you keep track as to how many quarts you used in your mix? The LT1 cooling system has an approximate 15qt capacity. Did you do all of this because there was a problem initially or was the car fine and then started overheating after all of these things were replaced? Where did you get the thermostat? Are you sure it is LT1 specific?
i had these problems before, and i replaced those in attempt to fix them.
Reply
Old Feb 14, 2010 | 05:03 PM
  #14  
Low N Slow's Avatar
TECH Enthusiast
iTrader: (4)
 
Joined: Mar 2005
Posts: 546
Likes: 0
From: Stanwood, WA
Default

Sounds like you replaced everything in the cooling system except the most important part, the radiator.
Get the thing warmed up and drop the cooling fans so you can feel the radiator, you will probably find only a small part of it hot the rest will be cool because it isn't circulating coolant thru it.
Reply
Old Feb 14, 2010 | 05:10 PM
  #15  
SS RRR's Avatar
Village Troll
20 Year Member
Liked
Loved
Community Favorite
iTrader: (2)
 
Joined: Oct 2002
Posts: 11,111
Likes: 596
From: Jackstandican
Default

Originally Posted by scj
i had these problems before, and i replaced those in attempt to fix them.
... and what about the rest of the questions?
Reply
Old Feb 15, 2010 | 12:43 AM
  #16  
thegooseman's Avatar
Banned
 
Joined: Nov 2008
Posts: 17
Likes: 0
From: Glendale CA
Default

You NEED to get a meziere EWP. I have the 55Gpm and it works at the speed WOT even if your at idle. good horse power gains also.
Reply
Old Feb 15, 2010 | 01:14 AM
  #17  
95CamaroLS1's Avatar
On The Tree
 
Joined: Nov 2009
Posts: 114
Likes: 0
From: Canby, Oregon
Default

Arghhh overheating issues frustrated me so much on my LT1! Good thing you know about LS1tech so you can get some good answers and figure out the problem. I just found out about this site after i took it out..
Reply
Old Feb 15, 2010 | 01:38 AM
  #18  
azzsmasher69's Avatar
Staging Lane
iTrader: (2)
 
Joined: Jun 2005
Posts: 90
Likes: 0
From: cocoa,fl
Default

Originally Posted by scj
if i give it gas while it's in gear to accelerate the car quickly overheats, if i throw it in neutral and let off the gas the car will quickly cool off, and it'll continue to do the same thing if i try and accelerate any. yet if i'm sitting at idle and i give it gas it will cool off a little, then after a few mins it will overheat.

wtf idk what to do.

help please
I had this problem a couple times.I had to bleed and bleed the system untill i puked. What happened on mine was i had a very small pin hole in the plastic tank on the radiator. I fixed that, no more problem. Another car had a bad radiator cap and another a corrosive steam pipe. Its possible that you still may have pockets of air in there. Could be causing circulation problems,etc.
Did you try a pressure check? Just giving some ideas.Hope this helps. Good luck
Reply




All times are GMT -5. The time now is 10:40 AM.