I changed the oil in the 2000 Bravada yesterday. Did the once over on all the fluids. I've been loosing about a pint of coolant about every three or four months. No leaking to the garage floor. I figure an internal gasket leak. There were about three different BAR'S LEAKS at AZ. I bought the liquid radiator stop leak in a gray 10oz plastic bottle which says it works on radiators, gaskets, heads, heater cores, blocks,... So cjparks what one of the Bar's Leaks products would you have recommended. I have not put anything in yet. I figured I may wait until it is down a bit again so I can dump it directly into the radiator but I may extract enough coolant to do it now. Any recommendations?
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an alternative browser.
You should upgrade or use an alternative browser.
GM 4.3 vortec vanishing coolant
- Thread starter EagleFTE
- Start date
- Status
- Not open for further replies.
Stop! Don't do it! Bars Leak is poison to your entire engine and cooling system. I used it...paid the price big time. I ended up replacing the engine, radiator, and heater core. That stuff absolutely does not work and clogs everything up causing serious problems. I tore apart the engine and found the stuff blocking a majority of the water ports. It should be a crime to sell and market it and similar products. Diagnose the car and replace the gasket or other problems as necessary. It will be less expensive in the long run. The car may be just overheating and boiling coolant out while you are driving. Flushing the cooling system and replacing the raditor cap is cheap preventative maintenance. If the oil is milky or there is moisture on the bottom of the oil cap, then you likely have a blown head gasket or warped heads. You can also check the vacuum with a gauge and have a shop check the cooling system pressure. There is also an antifreeze test kit that tests the coolant for oil contamination. Find the actual problem and fix it. While any engine can blow a head gasket, I don't believe the 4.3L is prone to it, so you may have a less expensive leak. Really, don't use the bars leak! If you don't have serious problems now, you will soon using that product.
These engines are notorious for leaking lower intake manifold gaskets. Coolent seeps into the lifter valley and contaminates the oil. In addition, these engines have problems with radiator caps.
You need to get the lower intake gaskets replaced with the Fel Pro Problem Solver gasket kit and get a new radiator cap on it.
Tahoskibum, I have used Bars Leak on several vehicles without any issues. In fact, I used it on a my father's old 98 Blazer when the heater core developed a leak and it sealed it perfectly. They add the stuff at the factory at GM. But it's not a long term solution to things like the GM intake gasket leaks.
You need to get the lower intake gaskets replaced with the Fel Pro Problem Solver gasket kit and get a new radiator cap on it.
Tahoskibum, I have used Bars Leak on several vehicles without any issues. In fact, I used it on a my father's old 98 Blazer when the heater core developed a leak and it sealed it perfectly. They add the stuff at the factory at GM. But it's not a long term solution to things like the GM intake gasket leaks.
I know that there is some sealant added to some factory fill. Chrysler does this and there is reportedly sealant in Mopar antifreeze for my 300. However, I don't believe that they use the extreme big ball stuff in volume sold by Bars Leak. I used a couple bottles of this stuff which temporarily clogged a blown head gasket on a Ford Explorer. It clogged the heater core, radiator and engine water ports. I have seen the damage first hand. I wasn't aware of the problem with lower intake gaskets. Do you know if the marine Chevy 4.3L has this problem? My boat has this engine.
Originally Posted By: TahoeSkiBum
Do you know if the marine Chevy 4.3L has this problem? My boat has this engine.
I don't know. A marine engine has an entirely different style cooling system.
The intake gasket problem is HUGE. It basically affects every GM 3.1, 3.4, 3.8, 4.3, 5.0, 5.7, and 7.4 liter engine.
Do you know if the marine Chevy 4.3L has this problem? My boat has this engine.
I don't know. A marine engine has an entirely different style cooling system.
The intake gasket problem is HUGE. It basically affects every GM 3.1, 3.4, 3.8, 4.3, 5.0, 5.7, and 7.4 liter engine.
Originally Posted By: TahoeSkiBum
However, I don't believe that they use the extreme big ball stuff in volume sold by Bars Leak.
Bars manufacturers the GM coolant sealant pellets. Exact same thing you find in auto parts stores.
However, I don't believe that they use the extreme big ball stuff in volume sold by Bars Leak.
Bars manufacturers the GM coolant sealant pellets. Exact same thing you find in auto parts stores.
Radiator cap you say.... I'm not used to Dex Cool (I'm using the Prestone version) but the cap had crystalized orange crud around the outer diameter and the fill neck had the same. I cleaned up the neck and took a toothbrush to the cap. The gasket in the cap is not very impressive. Perhaps I'm getting some coolant past the cap. This looks like a GM unique cap, not one that can be replaced by the standard old Standt cap. The coolant looks clean and a flashlight down the jeck shows no crud in the radiator. The oil looked normal and there is not tell tale signs of milky moisture on the oil cap.
GM 4.3 intake gasket failures are inevitable. Put the money aside, and get ready to pay for some cost cutting stupidity.
According to: http://www.imcool.com/articles/antifreeze-coolant/dexcool2007Part1.php and http://www.imcool.com/articles/antifreeze-coolant/dexcool-macs2001.php
Fill the overflow reservior to "hot" when cold and replace the cap with a Stant Model 10230.
Also interesting: http://www.imcool.com/articles/antifreeze-coolant/GMdocs/GMdocs.php Of particular interest from that page:
"Determine the "red X" on S/T w/4.3L:
When a Sundram Drop center design radiator cap is mounted at an angle, the design is sensitive to allowing debris to get under the valve and keep it open. Once this occurs, the valve will fail "open" and additional coolant will be lost more rapidly.
Iron oxide as the result of extended operation with a low level of coolant and a failed "open" radiator cap, is the root cause of the S/T coolant corrosion issue."
Fill the overflow reservior to "hot" when cold and replace the cap with a Stant Model 10230.
Also interesting: http://www.imcool.com/articles/antifreeze-coolant/GMdocs/GMdocs.php Of particular interest from that page:
"Determine the "red X" on S/T w/4.3L:
When a Sundram Drop center design radiator cap is mounted at an angle, the design is sensitive to allowing debris to get under the valve and keep it open. Once this occurs, the valve will fail "open" and additional coolant will be lost more rapidly.
Iron oxide as the result of extended operation with a low level of coolant and a failed "open" radiator cap, is the root cause of the S/T coolant corrosion issue."
Great info Onmo! Looks like a Stant 10230 is in the future for me. Fortunately I keep an eye on things and the level has not dropped below the radiator neck (thank you overflow tank). It would not surprise me to find that some people to go years without checking coolant. Big mistake with this set up.
I had an Astro that leaked like that. No signs anywhere except the disapearing coolant. Eventually it got worse and you could smell the coolant when it was hot, still nothing visually. Finally it got bad enough that it started to puddle slightly under the van. Even then I couldn't find it easily. Turned out to be the intake gasket, right on the front of the driver's side head. With the van I had to remove the AC compressor to find it.
Guess what I'm trying to say is take a very close look at the intake gaskets with a light.
Guess what I'm trying to say is take a very close look at the intake gaskets with a light.
Originally Posted By: TahoeSkiBum
Stop! Don't do it! Bars Leak is poison to your entire engine and cooling system. I used it...paid the price big time. I ended up replacing the engine, radiator, and heater core. That stuff absolutely does not work and clogs everything up causing serious problems. I tore apart the engine and found the stuff blocking a majority of the water ports. It should be a crime to sell and market it and similar products.
Please let me know what product you used and what type of vehicle. This is a very strong statement and we sell millions of bottles of the Bar's Leaks radiator type products a year and don't see how this could happen unless a product was used that was not compatible with antifreeze which should have been removed first. Did you happen to contact us on this? I would certainly like to discuss this issue further with you if possible. Keep in mind a regular bottle of Bar's Leaks has around 2 ounces of the sealing powder in there, so for this to clog a system without some other outside factors, is impossible.
Stop! Don't do it! Bars Leak is poison to your entire engine and cooling system. I used it...paid the price big time. I ended up replacing the engine, radiator, and heater core. That stuff absolutely does not work and clogs everything up causing serious problems. I tore apart the engine and found the stuff blocking a majority of the water ports. It should be a crime to sell and market it and similar products.
Please let me know what product you used and what type of vehicle. This is a very strong statement and we sell millions of bottles of the Bar's Leaks radiator type products a year and don't see how this could happen unless a product was used that was not compatible with antifreeze which should have been removed first. Did you happen to contact us on this? I would certainly like to discuss this issue further with you if possible. Keep in mind a regular bottle of Bar's Leaks has around 2 ounces of the sealing powder in there, so for this to clog a system without some other outside factors, is impossible.
Originally Posted By: EagleFTE
I changed the oil in the 2000 Bravada yesterday. Did the once over on all the fluids. I've been loosing about a pint of coolant about every three or four months. No leaking to the garage floor. I figure an internal gasket leak. There were about three different BAR'S LEAKS at AZ. I bought the liquid radiator stop leak in a gray 10oz plastic bottle which says it works on radiators, gaskets, heads, heater cores, blocks,... So cjparks what one of the Bar's Leaks products would you have recommended. I have not put anything in yet. I figured I may wait until it is down a bit again so I can dump it directly into the radiator but I may extract enough coolant to do it now. Any recommendations?
Intake gasket problems are common on these 4.3 engines. The liquid you purchased will work great. That has the same active stop leak ingredients as the tablets we sell to many of the car and truck companies which are used in these vehicles when new and in some when serviced at the dealer. Shake the bottle well and use the entire contents for your V6.
I changed the oil in the 2000 Bravada yesterday. Did the once over on all the fluids. I've been loosing about a pint of coolant about every three or four months. No leaking to the garage floor. I figure an internal gasket leak. There were about three different BAR'S LEAKS at AZ. I bought the liquid radiator stop leak in a gray 10oz plastic bottle which says it works on radiators, gaskets, heads, heater cores, blocks,... So cjparks what one of the Bar's Leaks products would you have recommended. I have not put anything in yet. I figured I may wait until it is down a bit again so I can dump it directly into the radiator but I may extract enough coolant to do it now. Any recommendations?
Intake gasket problems are common on these 4.3 engines. The liquid you purchased will work great. That has the same active stop leak ingredients as the tablets we sell to many of the car and truck companies which are used in these vehicles when new and in some when serviced at the dealer. Shake the bottle well and use the entire contents for your V6.
Thanks Cparks. I'm looking at the cap first and making sure the level stays high enough to keep the filler neck clean. If that doesn't work I will go with the Bars. One bottle for the 4.3 or maybe a half bottle for preventive puposes. Seems like preventive will not hurt given the problems with this engine. The sytem is still pretty shiney inside for nine years of service so It's not any where near as bad as some of the pictures of others I've seen.
- Status
- Not open for further replies.
Similar threads
- Replies
- 28
- Views
- 5K
- Replies
- 5
- Views
- 835
- Replies
- 6
- Views
- 2K
- Replies
- 7
- Views
- 9K
- Replies
- 18
- Views
- 7K