Leaking Coolant...HELP!
Thread Starter
Le Mans Master
Joined: Mar 2001
Posts: 9,464
Likes: 1
From: Modesto CA
Leaking Coolant...HELP!
I THINK I may have a cracked radiator, but it may just be the lower hose. Under my car, there is continually a puddle of coolant, and the LOW COOLANT light comes on when I'm on the freeway. (But goes off under normal city driving) Now, it doesn't drip at all while I'm moving, but once I stop or turn the car off, it leaks. It's not like a GUSHER, but it's more of a nag. The LOW COOLANT light basically only comes on when I get on the freeway. Any ideas? Also, how much would a new GM Radiator be? (Or aftermarket?) THANKS!
P.S.- I've already replaced the radiator cap, and I've "burped" it several times. Also, about 2 months ago, I took out the radiator and cleaned it off and cleaned out the cavity.
Hopefully it's just the lower radiator hose that's deteireorated.
[Modified by TIMSPEED, 11:15 AM 1/15/2002]
P.S.- I've already replaced the radiator cap, and I've "burped" it several times. Also, about 2 months ago, I took out the radiator and cleaned it off and cleaned out the cavity.
Hopefully it's just the lower radiator hose that's deteireorated.
[Modified by TIMSPEED, 11:15 AM 1/15/2002]
Burning Brakes
Joined: Nov 2000
Posts: 855
Likes: 0
Re: Leaking Coolant...HELP! (TIMSPEED)
You'll first have to find the source of the leak, but if its only leaking when stopped I'd check the bottom weep hole on the water pump. That is where mine was leaking from and I had similar symtoms. Moving would cause water/antifreeze to be blown away, not leaving evidence of source.
Burning Brakes
Joined: May 2000
Posts: 1,243
Likes: 1
From: Charlotte, NC USA
Re: Leaking Coolant...HELP! (TIMSPEED)
You might also check your "overflow" reservoir to see if perhaps it is the source of your leak. I had a similar problem that turned out to be the drain plug on my radiator. Mine did not stay "minor" for long though and I rather doubt it to be your problem. Good luck tracking it down...
Team Owner
Joined: Mar 1999
Posts: 89,144
Likes: 3
From: Life's tough, wear a helmet.
Re: Leaking Coolant...HELP! (TIMSPEED)
They're right. Find the leak first. No sense replacing non-leaking parts, right?
If it turns out to be the lower hose I can help. I just did mine over the holidays.
If it turns out to be the lower hose I can help. I just did mine over the holidays.
Team Owner
Joined: Nov 1999
Posts: 26,679
Likes: 17
From: This vette goes to 11 Milford MA
St. Jude Donor '03-'05
Re: Leaking Coolant...HELP! (Black84)
I have found that you have to "pack" the C4 radiator to get it full by revving the motor to about 2K by hand and filling the radiator with your other hand and then replacing the cap before letting it idle back.
Thread Starter
Le Mans Master
Joined: Mar 2001
Posts: 9,464
Likes: 1
From: Modesto CA
Re: Leaking Coolant...HELP! (Fastguy)
I don't think it's the water pump's weep hole, because the leaking looked to be coming out of the radiator cavity on the extreme passenger side. That's why I think it might be the lower radiator hose, or maybe a hole down there somewhere. Again, hopefully it's just the hose *fingers crossed*
Melting Slicks
Joined: Apr 2000
Posts: 3,198
Likes: 2
From: Northern CA
Re: Leaking Coolant...HELP! (TIMSPEED)
Tim, make sure you check the black plastic side tanks on the radiator for cracks. Check them closely with a flashlight, especially around the hose bosses. Also make sure the clamps are tight (obviously).
A new LT1/4 GM radiator is about $200 from Jeff Kopp, so I assume the L98 is similar. Although I would look into some of the aftermarket radiators which are supposed to be higher quality.
Good luck,
Jason
A new LT1/4 GM radiator is about $200 from Jeff Kopp, so I assume the L98 is similar. Although I would look into some of the aftermarket radiators which are supposed to be higher quality.
Good luck,
Jason
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
Safety Car
Joined: May 1999
Posts: 3,651
Likes: 5
From: Atlantis
Cruise-In I Veteran
Re: Leaking Coolant...HELP! (Fastguy)
Hey Fastguy,
--------------
I have found that you have to "pack" the C4 radiator to get it full by revving the motor to about 2K by hand and filling the radiator with your other hand and then replacing the cap before letting it idle back.
_______
My hand gets too tired when I try to rev mine to 2K by hand.
I need some sort of "hand cranker" on it.:reddevil
It's also too hard to do all that hand reving and fill the radiator with my other hand. Whew, can YOU do all that? :) :)
(you gotta visualize this one ;) ;) ;) ;)
--------------
I have found that you have to "pack" the C4 radiator to get it full by revving the motor to about 2K by hand and filling the radiator with your other hand and then replacing the cap before letting it idle back.
_______
My hand gets too tired when I try to rev mine to 2K by hand.
I need some sort of "hand cranker" on it.:reddevil
It's also too hard to do all that hand reving and fill the radiator with my other hand. Whew, can YOU do all that? :) :)
(you gotta visualize this one ;) ;) ;) ;)
Burning Brakes
Joined: Dec 2000
Posts: 1,161
Likes: 0
From: Orangeburg, NY
Re: Leaking Coolant...HELP! (TIMSPEED)
Before you do anything you have to find out where the leak is. It sounds like the system is loosing coolant only under pressure. Get hold of a pressure tester (PeP Boys and other large auto parts stores loan them) and check the system. It could be anything from a loose clamp to a cracked radiator.
Team Owner
Joined: Aug 1999
Posts: 69,020
Likes: 0
From: Bagpipes put the "fun" in "funeral"
Re: Leaking Coolant...HELP! (89 Bob L)
Check the hose going to your lower overflow tank. I had a mystery leak that I traced to the return hose being partially off the nozzle.
There are a bunch of places where the leak could be...
right now I've got a slow leak from a cheesy hose-splice job I did a while back.
There are a bunch of places where the leak could be...
right now I've got a slow leak from a cheesy hose-splice job I did a while back.
Team Owner
Joined: Nov 1999
Posts: 26,679
Likes: 17
From: This vette goes to 11 Milford MA
St. Jude Donor '03-'05
Re: Leaking Coolant...HELP! (VetNutJim)
Hey Fastguy,
--------------
I have found that you have to "pack" the C4 radiator to get it full by revving the motor to about 2K by hand and filling the radiator with your other hand and then replacing the cap before letting it idle back.
_______
My hand gets too tired when I try to rev mine to 2K by hand.
I need some sort of "hand cranker" on it.:reddevil
It's also too hard to do all that hand reving and fill the radiator with my other hand. Whew, can YOU do all that? :) :)
(you gotta visualize this one ;) ;) ;) ;)
--------------
I have found that you have to "pack" the C4 radiator to get it full by revving the motor to about 2K by hand and filling the radiator with your other hand and then replacing the cap before letting it idle back.
_______
My hand gets too tired when I try to rev mine to 2K by hand.
I need some sort of "hand cranker" on it.:reddevil
It's also too hard to do all that hand reving and fill the radiator with my other hand. Whew, can YOU do all that? :) :)
(you gotta visualize this one ;) ;) ;) ;)
If you pop the radiator cap and then lean over the right tire and open the throttle by hand to about 2k, you can watch the coolant level drop considerably. As you are doing this, you use your other hand to fill the radiator, no not your actual hand, but use your hand to pour a container of AF in there. Before you release the throttle, re-cap it or it will burp all over your driveway.:)
Racer
Joined: Jul 2001
Posts: 393
Likes: 1
From: Houston TX
Re: Leaking Coolant...HELP! (Fastguy)
I recently went through a similar problem with my LT4, replaced the lower hose only to find out that the plastic side tank was cracked. I bought a Griffin aluminum radiator but am seeing little difference other than the significant cutting of the pads necessary to install it. On the day I replaced my radiator I had to put three gallons of water in the car. Fortunately my new radiator had come in that day so I made it.
BTW you can have the engine hold low revs like that by propping the throttle cable mount open. A houskey is good for about 1500 RPMs in my car.
Hope this helps some!
Jason
[Modified by jsaunde2, 2:08 PM 1/16/2002]
BTW you can have the engine hold low revs like that by propping the throttle cable mount open. A houskey is good for about 1500 RPMs in my car.
Hope this helps some!
Jason
[Modified by jsaunde2, 2:08 PM 1/16/2002]
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Leaking Coolant...HELP! (VetNutJim)
VetNutJim, I think your grip on the throttle may be "inefficient". Try reaching over it and pushing & pulling at the same time. You sort of rotate the throttle about the throttle plate shaft.
Or you could just block the throttle open at about 2k RPM or so.
Or you could just block the throttle open at about 2k RPM or so.
