Adding Radiator Stop Leak.....a question for you?
Thread Starter
Burning Brakes
Joined: Oct 2008
Posts: 1,091
Likes: 45
From: Albuquerque New Mexico
Adding Radiator Stop Leak.....a question for you?
Should radiator stop leak be added to a 1990 via the outlet up on passenger side by the window, or via the radiator overflow? I guess same question could be asked of the antifreeze?
When i fill at the outlet up top it runs low, yet i have plenty in my overflow. Am i doing something wrong?
When i fill at the outlet up top it runs low, yet i have plenty in my overflow. Am i doing something wrong?
Drifting
Joined: Sep 2009
Posts: 1,794
Likes: 64
From: Roanoke Va
Should radiator stop leak be added to a 1990 via the outlet up on passenger side by the window, or via the radiator overflow? I guess same question could be asked of the antifreeze?
When i fill at the outlet up top it runs low, yet i have plenty in my overflow. Am i doing something wrong?
When i fill at the outlet up top it runs low, yet i have plenty in my overflow. Am i doing something wrong?
Maybe the seal is bad on the radiator cap?
Or on the over flow! mine was bad on my over flow and i was loseing antifreeze and coulden't figure out where it was going till i got some teflon tape and put it in threads and fixed it!
Team Owner
Joined: Dec 2007
Posts: 20,974
Likes: 261
If you are referring to the additive to block a leak, than it should go in under the metal cap itself, and let it run for a while.
PEOPLE HERE WILL TELL YOU NOT TO USE IT.
I was advised by everyone not to, and I did 4 years ago on a daily driver, and so far it is still fine, and everything still works.
I might not use it on a vette though, just depends on how important your car is to you.
PEOPLE HERE WILL TELL YOU NOT TO USE IT.
I was advised by everyone not to, and I did 4 years ago on a daily driver, and so far it is still fine, and everything still works.
I might not use it on a vette though, just depends on how important your car is to you.
Tech Contributor
Joined: Oct 2008
Posts: 3,729
Likes: 190
From: Custer, WI
If you are referring to the additive to block a leak, than it should go in under the metal cap itself, and let it run for a while.
PEOPLE HERE WILL TELL YOU NOT TO USE IT.
I was advised by everyone not to, and I did 4 years ago on a daily driver, and so far it is still fine, and everything still works.
I might not use it on a vette though, just depends on how important your car is to you.
PEOPLE HERE WILL TELL YOU NOT TO USE IT.
I was advised by everyone not to, and I did 4 years ago on a daily driver, and so far it is still fine, and everything still works.
I might not use it on a vette though, just depends on how important your car is to you.
Put some in a 94 sunbird i bought for $50 and it worked for the 5 months I drove it.
A lot of the people on the forum will tell you to not use it because they believe that it's a sin or something lol
Team Owner
Joined: Feb 2003
Posts: 54,155
Likes: 9,464
From: Sitting in his Nowhere land Hanover Pa
2024 C2 of the Year Finalist - Unmodified
2015 C2 of Year Finalist
it might start to stop anti freeze some places you might not want to think about it. like the heater core. just something to think about
Max G’s
Joined: Nov 2008
Posts: 2,751
Likes: 79
From: Monroe OH
NCM Sinkhole Donor
It's not a sin, it's a cheap band aid. Long Term effects are not worth the short term gain. Bottom line is INSTALL A NEW RADIATOR CAP.
Race Director
Joined: Jun 2009
Posts: 10,428
Likes: 9
From: Southside of Western Norte Americano State of Confusion, ColoFornia
St. Jude '13
Radiator stop leak isnt a sin... Its just not the best approach to the problem.. If the car leaks, Fix the leak.
Stop leak varies form brand to brand and I have used it several times on the farm equipment and other items where you just have to keep it going a few days (like during harvest).
Its just a band aid at best and it will leak again sooner or later.
Stop leak varies form brand to brand and I have used it several times on the farm equipment and other items where you just have to keep it going a few days (like during harvest).
Its just a band aid at best and it will leak again sooner or later.
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Le Mans Master
Joined: Dec 2005
Posts: 5,198
Likes: 10
From: Homestead Fl
St. Jude Donor '06-'07-'10-'11-'12-'13-'14
Radiator stop leak isnt a sin... Its just not the best approach to the problem.. If the car leaks, Fix the leak.
Stop leak varies form brand to brand and I have used it several times on the farm equipment and other items where you just have to keep it going a few days (like during harvest).
Its just a band aid at best and it will leak again sooner or later.
Stop leak varies form brand to brand and I have used it several times on the farm equipment and other items where you just have to keep it going a few days (like during harvest).
Its just a band aid at best and it will leak again sooner or later.
Find the leak and fix it is the best advice.
Le Mans Master
Joined: Apr 2005
Posts: 6,413
Likes: 9
From: The Old Dominion
You would want to add it at the pressurized tank by the passenger window. This is also where you would add antifreeze if you were changing it.
The white tank down by the passenger side headlight is the unpressurized overflow. This means it sees very little coolant flow, it only gets a little extra coolant when the engine is hot, and returns a little coolant as the engine cools down after shutoff.
The white tank down by the passenger side headlight is the unpressurized overflow. This means it sees very little coolant flow, it only gets a little extra coolant when the engine is hot, and returns a little coolant as the engine cools down after shutoff.
Melting Slicks
Joined: Jul 2008
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From: Ottawa Ontario
Safety Car
Joined: Jan 2004
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Team Owner
Joined: Jul 2004
Posts: 28,501
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From: Hartford WI
Why band aid a thing like that? Why not just fix it and have peace of mind?
Le Mans Master
Joined: May 1999
Posts: 6,520
Likes: 1,306
From: Windermere FL
It is a bandaid, but sometimes you got to wonder. I used it in a POS Blazer beater and it fixed all the leaks. Yeah it looks pretty nasty afterward. But I found that one it blocked it, it seemed to stay sealed even after changing the fluid. Maybe luck (for once). For all I know that thing is still going thru the mud pits somewhere!
No, I would not use it for a radiator cap leak. Replace the cap with an OEM of the same pressure.
The only time I would think about using it in the Vette would be for the dreaded heater core. That thing just give me the ******* and if mine ever leaked I might dump the car to tell you the truth. I have a real phobia with Part #1. That aside, I would be tempted to bypass it first. With it bypassed, I might be tempted to try to find someone to replace it for less than $1,000
No, I would not use it for a radiator cap leak. Replace the cap with an OEM of the same pressure.
The only time I would think about using it in the Vette would be for the dreaded heater core. That thing just give me the ******* and if mine ever leaked I might dump the car to tell you the truth. I have a real phobia with Part #1. That aside, I would be tempted to bypass it first. With it bypassed, I might be tempted to try to find someone to replace it for less than $1,000
Safety Car
Joined: Nov 2008
Posts: 4,328
Likes: 15
From: Jacksonville FL
You wanna come pull my engine? I live in BFE and that kid you talk about is my neighbor and he said its ok its only a drip.
Seriously, when I rebuild the engine I will replace the freeze plugs. And flush the system.
And No I wouldnt use it for a radiator cap nor a hail mary play on a shot radiator. Its a little easier to pull a radiator than an engine
Seriously, when I rebuild the engine I will replace the freeze plugs. And flush the system.
And No I wouldnt use it for a radiator cap nor a hail mary play on a shot radiator. Its a little easier to pull a radiator than an engine
