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

vanishing coolant

Thread Tools
 
Search this Thread
 
Old Mar 9, 2011 | 08:34 PM
  #1  
93z28ltone's Avatar
Thread Starter
On The Tree
 
Joined: Feb 2011
Posts: 169
Likes: 0
Default vanishing coolant

I went out started my car today when I started it I noticed my low coolant light was on so with it running took the cap off the radiator and filled it back it took a 1/2 gug of coolant to do it I have not noticed any leaks I've changed the plugs no coolant on plugs changed the oil this last weekend no milkness in it any other ideas would be helpful
Reply
Old Mar 9, 2011 | 09:03 PM
  #2  
James Montigny's Avatar
11 Second Club
iTrader: (13)
 
Joined: May 2006
Posts: 2,843
Likes: 0
Default

Originally Posted by 93z28ltone
I went out started my car today when I started it I noticed my low coolant light was on so with it running took the cap off the radiator and filled it back it took a 1/2 gug of coolant to do it I have not noticed any leaks I've changed the plugs no coolant on plugs changed the oil this last weekend no milkness in it any other ideas would be helpful
Is this the first time you've noticed it low?
And is there coolant in your overflow tank?
Reply
Old Mar 9, 2011 | 10:21 PM
  #3  
rich5368's Avatar
TECH Regular
iTrader: (2)
 
Joined: Apr 2010
Posts: 442
Likes: 0
From: Cheyenne, WY
Default

Could be burning it. Sounds like it could be the beginning of head gasket trouble.
Reply
Old Mar 9, 2011 | 11:11 PM
  #4  
shbox's Avatar
TECH Veteran
15 Year Member
Liked
 
Joined: Dec 2008
Posts: 4,147
Likes: 62
From: Little Rock, AR
Default

Could be a slow leak at a hose, radiator tank, pipe from radiator to coolant reservoir, etc. Sometimes they never reach the ground.
Reply
Old Mar 9, 2011 | 11:36 PM
  #5  
myltwon's Avatar
TECH Addict
iTrader: (1)
 
Joined: Jul 2004
Posts: 2,965
Likes: 7
From: Palm Harbor, FL
Default

reservoir can be hard one to spot, also small leak in a hose.

best thing to do is to rent/buy a cooling system pressure tester or atleast get under the car and clean off everything then check again after you've ran it for a bit.
Reply
Old Mar 9, 2011 | 11:42 PM
  #6  
93z28ltone's Avatar
Thread Starter
On The Tree
 
Joined: Feb 2011
Posts: 169
Likes: 0
Default

none in the res ether which caused the coolant light and yeah when i bought it top hose clamps were bad and leaking coolant i change the clamps and that fixed that leak and havent noticed any coolant lose until now i check my coolant every week also ive notice under load it starts to get hot and i have a 160 therm in it when i say hot i mean right between a half and 3/4 on the temp gage also my heater hasnt worked since ive owned the car it dont blow hot when its freezing out side but when its warm it works just fine
Reply
Old Mar 9, 2011 | 11:44 PM
  #7  
myltwon's Avatar
TECH Addict
iTrader: (1)
 
Joined: Jul 2004
Posts: 2,965
Likes: 7
From: Palm Harbor, FL
Default

heater core could be leaking, check the passanger floor area for wetness
Reply
Old Mar 9, 2011 | 11:46 PM
  #8  
93z28ltone's Avatar
Thread Starter
On The Tree
 
Joined: Feb 2011
Posts: 169
Likes: 0
Default

done that and no coolant leak
Reply
LS1 Tech Stories

The Best V8 Stories One Small Block at Time

story-0

Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

 Pouria Savadkouei
story-1

Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

 Verdad Gallardo
story-2

7 Most Reliable High-Performance Engines GM Has Ever Built

 Verdad Gallardo
story-3

Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

 Verdad Gallardo
story-4

6 Common C5 Corvette Failures and What's Involved In Repairing Them

 Pouria Savadkouei
story-5

Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

 Verdad Gallardo
story-6

Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

 Pouria Savadkouei
story-7

Top 10 Most Powerful Chevy Trucks Ever Made!

 
story-8

Hennessey's New Supercharged Silverado ZR2 Has 700 HP

 Verdad Gallardo
story-9

Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

 Verdad Gallardo
Old Mar 9, 2011 | 11:56 PM
  #9  
myltwon's Avatar
TECH Addict
iTrader: (1)
 
Joined: Jul 2004
Posts: 2,965
Likes: 7
From: Palm Harbor, FL
Default

alright well next step would be a pressure test, anything else is guessing and feeling for wet spots.
Reply
Old Mar 10, 2011 | 12:11 AM
  #10  
93z28ltone's Avatar
Thread Starter
On The Tree
 
Joined: Feb 2011
Posts: 169
Likes: 0
Default

how do you do the pressure check
Reply
Old Mar 10, 2011 | 07:04 AM
  #11  
shbox's Avatar
TECH Veteran
15 Year Member
Liked
 
Joined: Dec 2008
Posts: 4,147
Likes: 62
From: Little Rock, AR
Default

Originally Posted by 93z28ltone
how do you do the pressure check
You rent or buy a pressure tester, pump the system up to operating pressure and look for leaks. This way you can do it safely with the engine cold.
Reply
Old Mar 10, 2011 | 07:09 AM
  #12  
lt170chevelle's Avatar
TECH Fanatic
iTrader: (2)
 
Joined: Jul 2006
Posts: 1,153
Likes: 1
From: BS,TX
Default

I had a very similar problem last year and ended up being the begining of a head gasket. Took a while before it got worst.

X2 on the pressure test..rent one from a parts store.
Reply
Old Mar 10, 2011 | 10:42 AM
  #13  
~BuMps AloT~'s Avatar
TECH Apprentice
iTrader: (5)
 
Joined: Jan 2007
Posts: 371
Likes: 0
From: Hays
Default

Do a pressure test
Reply
Old Mar 10, 2011 | 10:51 AM
  #14  
James Montigny's Avatar
11 Second Club
iTrader: (13)
 
Joined: May 2006
Posts: 2,843
Likes: 0
Default

Originally Posted by shbox
You rent or buy a pressure tester, pump the system up to operating pressure and look for leaks. This way you can do it safely with the engine cold.
I ran into that a few years back, the stupid cap wasn't holding pressure.
I didn't realize where my coolant was going until we pumped it up to 18psi

Cheap fix; new radiator cap.
Reply
Old Mar 10, 2011 | 11:01 AM
  #15  
idformula's Avatar
TECH Regular
 
Joined: May 2010
Posts: 481
Likes: 0
Default

I had a similar problem, I used a jug of pre mix over the course of a coupple of months so it was a slow leak, and it turned out being on the pass side of the radiator where it mounts developed a crack. X2 on doing a pressure test.
Reply
Old Mar 12, 2011 | 03:46 PM
  #16  
93z28ltone's Avatar
Thread Starter
On The Tree
 
Joined: Feb 2011
Posts: 169
Likes: 0
Default

doing a pressure test today im waiting for the car to cool down so i can do it i noticed alot of coolant around the overflow tank down underneath the battery and around the lid to it ive been putting the coolant in the radiator it self so i am going to check around there to see if theres a leak
Reply
Old Mar 12, 2011 | 04:13 PM
  #17  
SS RRR's Avatar
Village Troll
20 Year Member
Liked
Loved
Community Favorite
iTrader: (2)
 
Joined: Oct 2002
Posts: 11,111
Likes: 598
From: Jackstandican
Default

Check around the seams of the radiator as well.
Reply
Old Mar 12, 2011 | 04:45 PM
  #18  
93z28ltone's Avatar
Thread Starter
On The Tree
 
Joined: Feb 2011
Posts: 169
Likes: 0
Default

i check the pressure and the return coolant line to the radiator from the back of the heads was leaking i turned out to be a bad clamp now i checked it agian after that and it holds presure for about 5 mins then starts to go down really slowly were before i did that it was loosing presure fast any other ideas ive checked the radiator and all the hoses
Reply
Old Mar 12, 2011 | 04:46 PM
  #19  
joelster's Avatar
10 Second Club
15 Year Member
Photogenic
Liked
Loved
 
Joined: Oct 2007
Posts: 2,630
Likes: 28
Default

Reach behind each cylinder head and run your fingers along the banjo bolts on the back of each cylinder head. A small leak there would run down the bellhousing and be pretty hard to trace.
Reply
Old Mar 12, 2011 | 04:57 PM
  #20  
Cheap Guy's Avatar
TECH Resident
iTrader: (3)
 
Joined: May 2007
Posts: 882
Likes: 1
Default

As mentioned above, vanishing coolant was the sign my head gasket was going. It was just small enough that my oil was not milky and it actually took a while for it to overhead. When the head was off, we could see where the gasket failed. The only way I found out (other than it overheating) was a pressure test.
Reply



All times are GMT -5. The time now is 12:25 AM.

story-0
Topdon ONE vs. Artidiag 800 BT2: Which is the Diagnostic Tablet For You?

Slideshow: We take a close look at the ONE and Artidiag 800BT2 diagnostic tools from Topdon and the reasons to buy one over the other.

By Pouria Savadkouei | 2026-05-28 11:05:11


VIEW MORE
story-1
Gas Monkey Built a 6-Wheel Ferrari Testarossa With a Corvette LT4 Engine

Slideshow: The controversial Ferrari F6 swaps its original flat-12 for a Corvette Z06-derived LT4 V8 and sends power to four rear wheels through a custom-built drivetrain.

By Verdad Gallardo | 2026-05-26 18:23:54


VIEW MORE
story-2
7 Most Reliable High-Performance Engines GM Has Ever Built

Slideshow:These GM engines didn't just make huge power, they survived abuse, boost, track days, and six-digit mileage with a reputation for refusing to quit.

By Verdad Gallardo | 2026-05-21 16:45:27


VIEW MORE
story-3
Amazing '71 Camaro Restomod Is Modern Muscle Car Under the Skin

Slideshow: This heavily modified 1971 Camaro mixes classic muscle car styling with a fifth-generation Camaro interior and modern LS3 power.

By Verdad Gallardo | 2026-05-12 18:06:42


VIEW MORE
story-4
6 Common C5 Corvette Failures and What's Involved In Repairing Them

Slideshow: From wobbling harmonic balancers to failed EBCMs, these are the issues that define long-term C5 ownership and what repairs typically involve.

By Pouria Savadkouei | 2026-05-07 18:44:57


VIEW MORE
story-5
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph

Slideshow: A modern Camaro transformed into a retro icon, this limited-run "Bandit" build blends nostalgia with brute force in a way few revivals manage.

By Verdad Gallardo | 2026-04-21 13:57:02


VIEW MORE
story-6
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked

Slideshow: Cadillac didn't just crash the high-performance luxury vehicle party, it showed up loud, supercharged, and occasionally a little unhinged...

By Pouria Savadkouei | 2026-04-16 10:05:15


VIEW MORE
story-7
Top 10 Most Powerful Chevy Trucks Ever Made!

Slideshow: Top ten most powerful Chevy trucks ever made

By | 2026-03-25 09:22:26


VIEW MORE
story-8
Hennessey's New Supercharged Silverado ZR2 Has 700 HP

Slideshow: Hennessey has turned the Silverado ZR2 into a 700-hp off-road monster with supercharged V8 power and a limited production run.

By Verdad Gallardo | 2026-03-24 18:57:52


VIEW MORE
story-9
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes

Slideshow: A one-off sports car that looks like a vintage Italian exotic-but hides a C6 Corvette underneath-just sold for the price of a new mid-engine Corvette.

By Verdad Gallardo | 2026-03-23 18:53:41


VIEW MORE