1995 Z28 Disappearing Coolant... - LS1LT1 Forum : LT1, LS1, Camaro, Firebird, Trans Am, Engine Tech Forums

Welcome to LS1LT1.com/LS3forums.com - please click here to register...

LS1LT1 Forum : LT1, LS1, Camaro, Firebird, Trans Am, Engine Tech Forums
Presented by:

New User? Register
LS1 Forums Register Photo Gallery Tech/FAQ Members List Calendar Auto Loans Search Today's Posts Mark Forums Read Auto EscrowInsurance
Premium Membership Videos Perf Tools Mobile/iPhone Link to Us! Social Groups Follow LS1LT1 on Twitter


Go Back   LS1LT1 Forum : LT1, LS1, Camaro, Firebird, Trans Am, Engine Tech Forums > Engine Tech > LT1 | LT4 | L99 Engine Tech

LS1LT1.com is the premier Pontiac Forum on the internet. Registered Users do not see the above ads.
Reply
 
Share LinkBack Thread Tools
Old 07-07-2009, 10:29 PM   #1
Regular Member
 
Join Date: Jul 2009
Posts: 24
7Charlie user's tech expertise is unknown at this point
Default 1995 Z28 Disappearing Coolant...

Alright guys, I've searched the forums on here, and can't find anything that sounds related.

I've got a 95 Z28, bone stock, 109,000 miles on it. From about 100k to 107k, the low coolant light had been occasionally coming on. I ended up replacing the radiator, H20 pump, heater core, thermostat, hoses, etc.

Over the past 2k, I've had to add about 3 gallon of coolant. Here's the kickers that make no sense to me...

A) I have no visible leaks under the vehicle, ever.
B) Once the engine is warm, I get no steam or water vapor out of the tailpipe.
C) No coolant contamination of the motor oil.
D) No oil contamination of the coolant.
E) Just recently pulled the valve covers to quiet down a loose rocker - the tops of both heads were spotless.
F) No coolant contamination of the auto trans fluid.

Before I start to spend mucho bucks... any advice? I'd think with a cracked block / head / blown gasket, I'd see some contamination somewhere.

Anybody ever had anything like this???

Thanks in advance for your responses.

//7C
7Charlie is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Sponsored Links
Advertisement
 
Old 07-07-2009, 10:36 PM   #2
CKJ
Guest
 
Posts: n/a
Default

The one thing you could do but its a royal pain is to pull every plug in the motor to see one is being "steam cleaned"
 
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 07-07-2009, 10:40 PM   #3
Regular Member
 
alpine247's Avatar
 
Join Date: Aug 2008
Location: willow springs NC
Posts: 607
alpine247 Apprentice Level Tech I
Default

had the same problem and came to find out it was the radiator cap was bad.

so give that a try ...
__________________
94 Z28 with 96 impala LT1, Auto A4,3.73's, (Mods) CAI,Elbow,Mids headers,Msd Wires/Coil, Cat delete,Built 4l60e/with shift kit&2500 stall,Dyno Tune,Chokemaster muffler,Panhard bar,lca arm's and all the free mods... And Dyno at 286hp/342tq.
alpine247 is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 07-07-2009, 11:12 PM   #4
Regular Member
 
Join Date: Jul 2009
Location: Catoosa, Oklahoma
Posts: 148
blk99ek user's tech expertise is unknown at this point
Default

I would get a leak down tester and pump the system up and wait and see if you can't see anything. Look under the throttle body on the passanger side and see if their is any coolant down their
blk99ek is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 07-07-2009, 11:43 PM   #5
Regular Member
 
shoebox's Avatar
 
Join Date: Aug 2006
Location: Little Rock, AR
Posts: 5,976
shoebox Tradesman Level Tech II
Default

Check the overflow pipe that runs under the battery to the remote reservoir. It can leak very slowly to where you will never see any coolant hit the ground. You will have to remove the battery.
shoebox is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 07-07-2009, 11:46 PM   #6
Regular Member
 
96RedZ28's Avatar
 
Join Date: Jul 2009
Location: Somewhere
Posts: 170
96RedZ28 user's tech expertise is unknown at this point
Default

I just got done with that problem today... Wondered where all my coolant was going when it wasnt on the ground... It got hot and turned into steam, found out radiator cap was bad.
__________________
96 Z - A4 - 3.90 - SLP CAI - 160 Stat - Borla 3" Adjustable - Manual Fan Switch - TB Bypass - T-Tops - Pure awesomeness. -SOLD

02 Z28 35th Anniversary - M6 - 4.10 - FTP 98mm Intake - SLP DOTL 3" - SLP Strut Bar - SLP 85mm MAF - UMI PHB - UMI LCAs - FRA - 17" Chrome ZR1's - Hurst Shifter - AAM diff cover - Auburn diff - Bilstein Shocks - SLP SFC's, Hotchkis 35mm sway bar - Tune-330RWHP 341RWTQ
--Soon - FAST 102/92
96RedZ28 is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 07-11-2009, 12:04 AM   #7
Regular Member
 
Join Date: Jul 2009
Posts: 24
7Charlie user's tech expertise is unknown at this point
Default Results...

Thanks for all the advice guys - found the following.

Got a leakdown tester. Tested the radiator cap - it would pop off around 16-17 psi, but would then quickly leak down to about 7-8 psi. From what I can understand, this indicated the cap is bad, correct? My understanding is that the cap should "pop" in the 17-18 range and then hold that pressure, right?

Put the tester on the radiator itself - Pumped it up to 18 psi. After about 2 minutes, I would say that I was down to about 17.75... very little to no loss. Is this enough to even worry about? Or should I just get a high quality "stop-leak" additive, run it for a few days, and then test again?

Thanks for your help in advance.
7Charlie is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 07-11-2009, 12:08 AM   #8
CKJ
Guest
 
Posts: n/a
Default

Leave the tester on for much more than 2 minutes. I usually put them on and walk away for 15-20 minutes.

I've personally never tested a cap for I don't have that adapter for my pressure check setup. If in question, just buy a new one Can't run no more than 5-7 bucks just a guess.
 
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 07-11-2009, 12:12 AM   #9
Regular Member
 
Join Date: Jul 2009
Posts: 24
7Charlie user's tech expertise is unknown at this point
Default

In reference to the tester - will do tomorrow.

Should I see any leak down in 20 minutes? Is there an "acceptable" figure?


Thanks.
7Charlie is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 07-11-2009, 12:21 AM   #10
CKJ
Guest
 
Posts: n/a
Default

You shouldn't have any if you want to get 100% technical. But I would imagine if it sticks to that 1/4 PSI then you shouldn't have any real problems. I think 1/2 psi would bug me enough to where i'd start searching.
 
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 07-11-2009, 10:01 PM   #11
Supporting Member
 
Dennis93TA's Avatar
 
Join Date: Mar 2007
Location: Charleston, SC
Posts: 1,035
Dennis93TA Apprentice Level Tech III
Default

I have a question, Do you hear any "bubbling" in the radiator after you shut the car down after the car is hot?

Reason I ask is not many people could tell me why one of my cars would do this, it would lose coolant but I could not locate the leak. After buying a coolant test I found my headgasket was bad. I had no cross contamination of any fluids and nothing out the tail pipe. Just bubbles in the radiator. It's a wierd situation where the pistons will push air(exhaust) into the coolant passages but not the other way around.

Just a thought.
__________________
I Own No Cool Cars:candlesad
1967 Camaro: Under The Knife
2008 2500HD 4x4 Duramax: Slow
Dennis93TA is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 07-11-2009, 10:16 PM   #12
Regular Member
 
Join Date: Jul 2009
Posts: 24
7Charlie user's tech expertise is unknown at this point
Default

I'll check on the bubbling - I can't say that I have heard it, but I don't know if I have paid enough attention after a hot shutdown.

I redid the leakdown test, found about 1.5 psi loss after 20 minutes.

I'm going to try a combustion gas leak test on the cooling system next, just to verify that I'm getting contamination.

Thanks for the heads up. Next time I get her warm, I'll be sure to listen to the cooling system for a while.
7Charlie is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 07-12-2009, 12:28 AM   #13
CKJ
Guest
 
Posts: n/a
Default

Quote:
Originally Posted by Dennis93TA View Post
I have a question, Do you hear any "bubbling" in the radiator after you shut the car down after the car is hot?

Reason I ask is not many people could tell me why one of my cars would do this, it would lose coolant but I could not locate the leak. After buying a coolant test I found my headgasket was bad. I had no cross contamination of any fluids and nothing out the tail pipe. Just bubbles in the radiator. It's a wierd situation where the pistons will push air(exhaust) into the coolant passages but not the other way around.

Just a thought.
Hell Dennis, if thats the case almost every one of my cars would have a bad gasket. I know my 92 Cadi does it I don't know...i'm just...lost, forgive me.
 
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 07-13-2009, 12:00 PM   #14
Supporting Member
 
Dennis93TA's Avatar
 
Join Date: Mar 2007
Location: Charleston, SC
Posts: 1,035
Dennis93TA Apprentice Level Tech III
Default

There is a tester they sell, I forget the name of it, you take off the radiator cap and push this thing into the radiator, fill it up with the special fluid and use the hand pump. If there is any exhaust gases in the coolant it will turn the special fluid a diff color, which either means you have a bad head gasket or a cracked head. I have the tester somewhere, I may have to dig it out and get the name of it, I think it is simply call a "Block Tester"
__________________
I Own No Cool Cars:candlesad
1967 Camaro: Under The Knife
2008 2500HD 4x4 Duramax: Slow
Dennis93TA is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Old 07-13-2009, 12:11 PM   #15
Regular Member
 
Join Date: Jul 2009
Posts: 24
7Charlie user's tech expertise is unknown at this point
Default

Yeah, that's next on the list. I've currently got an issue with my rocker nuts backing off, so I'm trying to get through 1 issue at a time. Thanks though.
7Charlie is offline  
Digg this Post!Add Post to del.icio.usBookmark Post in TechnoratiTweet this Post!
Reply With Quote
Sponsored Links
Advertisement
 
Reply

Bookmarks

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


» Recommended
Find technical articles on a Chevy Corvette, including tips and tricks on a Chevy Camaro and expert advice for Pontiac Firebird, along with reviews on the Cadillac CTS.
» Auto Insurance
» Sponsors
Powered by vBadvanced CMPS v3.2.2

All times are GMT -5. The time now is 11:55 PM.



Powered by vBulletin® Copyright ©2000 - 2014, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.5.2
Copyright © 2005 - 2011 by LS1LT1.com

Our Friends:


Illegal Street Racing | Super Cars | LT1 Tech Articles