Is this a blown head gasket?
Is this a blown head gasket? Hey all. Recently did a mild tune up on an 02 ws6 that I'm working on. Tune up consisted of new water pump, valve cover gaskets, intake gaskets, valley gasket, oil pressure sender, plugs and wires. This work was iniated due to severely leaking valve cover gaskets that were leaking onto the manifolds and causing a faint under Hood smoke. Or so I thought.
After completing this work I started the motor and allowed it to reach operating temp. After about 15 minutes i noticed a very faint white smoke coming from the driver side. I gave the motor some rpm which seemed to increase the volume of the smoke. It seems to be rising from below #5 spark plug.
I hadn't fully burped the coolant system yet, so I popped the radiator cap off and watched a few bubbles come from the steam inlet, and added some 50/50. Motor is still running at this point, going on 20 minutes. While I was waiting on more air bubbles, decided to take another look at the smoke coming from drivers side. I could be wrong on this, but It seemed to me that it was smoking less with the radiator cap off.
Once this dawned on me I figured why not put the cap on and see if it increases. Well, coolant had started to bubble over so i decided to kill the motor. When I did, a mini volcanoe of antifreeze came blasting out of the radiator. If I had to wager a guess, I'd say a solid gallon came out.
I'm not 100% sure what to think about it. When I got this car it did have some evidence of a stop leak type substance around the radiator cap area. And im pretty confident the smoke is not old oil burning off still.
Thoughts?
After completing this work I started the motor and allowed it to reach operating temp. After about 15 minutes i noticed a very faint white smoke coming from the driver side. I gave the motor some rpm which seemed to increase the volume of the smoke. It seems to be rising from below #5 spark plug.
I hadn't fully burped the coolant system yet, so I popped the radiator cap off and watched a few bubbles come from the steam inlet, and added some 50/50. Motor is still running at this point, going on 20 minutes. While I was waiting on more air bubbles, decided to take another look at the smoke coming from drivers side. I could be wrong on this, but It seemed to me that it was smoking less with the radiator cap off.
Once this dawned on me I figured why not put the cap on and see if it increases. Well, coolant had started to bubble over so i decided to kill the motor. When I did, a mini volcanoe of antifreeze came blasting out of the radiator. If I had to wager a guess, I'd say a solid gallon came out.
I'm not 100% sure what to think about it. When I got this car it did have some evidence of a stop leak type substance around the radiator cap area. And im pretty confident the smoke is not old oil burning off still.
Thoughts?
if the system hadnt burped you probably had a bubble. check to make sure the t-stat bleed orifice is at the top and run it again. I have had the best luck pouring cooland directly down the outlet to fill the block to the heads.
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Hey all. Recently did a mild tune up on an 02 ws6 that I'm working on. Tune up consisted of new water pump, valve cover gaskets, intake gaskets, valley gasket, oil pressure sender, plugs and wires. This work was iniated due to severely leaking valve cover gaskets that were leaking onto the manifolds and causing a faint under Hood smoke. Or so I thought.
After completing this work I started the motor and allowed it to reach operating temp. After about 15 minutes i noticed a very faint white smoke coming from the driver side. I gave the motor some rpm which seemed to increase the volume of the smoke. It seems to be rising from below #5 spark plug.
I hadn't fully burped the coolant system yet, so I popped the radiator cap off and watched a few bubbles come from the steam inlet, and added some 50/50. Motor is still running at this point, going on 20 minutes. While I was waiting on more air bubbles, decided to take another look at the smoke coming from drivers side. I could be wrong on this, but It seemed to me that it was smoking less with the radiator cap off.
Once this dawned on me I figured why not put the cap on and see if it increases. Well, coolant had started to bubble over so i decided to kill the motor. When I did, a mini volcanoe of antifreeze came blasting out of the radiator. If I had to wager a guess, I'd say a solid gallon came out.
I'm not 100% sure what to think about it. When I got this car it did have some evidence of a stop leak type substance around the radiator cap area. And im pretty confident the smoke is not old oil burning off still.
Thoughts?
After completing this work I started the motor and allowed it to reach operating temp. After about 15 minutes i noticed a very faint white smoke coming from the driver side. I gave the motor some rpm which seemed to increase the volume of the smoke. It seems to be rising from below #5 spark plug.
I hadn't fully burped the coolant system yet, so I popped the radiator cap off and watched a few bubbles come from the steam inlet, and added some 50/50. Motor is still running at this point, going on 20 minutes. While I was waiting on more air bubbles, decided to take another look at the smoke coming from drivers side. I could be wrong on this, but It seemed to me that it was smoking less with the radiator cap off.
Once this dawned on me I figured why not put the cap on and see if it increases. Well, coolant had started to bubble over so i decided to kill the motor. When I did, a mini volcanoe of antifreeze came blasting out of the radiator. If I had to wager a guess, I'd say a solid gallon came out.
I'm not 100% sure what to think about it. When I got this car it did have some evidence of a stop leak type substance around the radiator cap area. And im pretty confident the smoke is not old oil burning off still.
Thoughts?
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Ok cool. So at least the volcanoes doesn't indicate anything wrong. So if I do have a head gasket leaking to the exterior of the motor, would it make sense that the steam/smoke I'm seeing would be more pronounced with the cap on vs cap off?
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Verdad Gallardo Ya that's what I'm thinking. Aside from the filter and oil cooler bypass,There isn't much below the #5 area that I could see causing this besides the head gasket. Being that I suspect it's leaking externally, would a pressure test be the only way to test it?
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Joined: Jun 2016
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I would THINK cap-on, which would tend to pressurize any leak more than cap-off, pushing more steam out of the leak. Just guessing here....
I would definitely recommend a pressure test.
I would definitely recommend a pressure test.
Well I think I my problem was not a head gasket. I jacked the front of the car up and set it down with 6x6's under the front tires.
Filled up the radiator and started the car. Let it idle a solid 30 minutes. To my delight, there was No steam/smoke to be seen, although I was detecting the coolant smell but that could have been from yesterday's boil over.
Crawled under the car with a flashlight to see if I could spot a leaky head gasket, but instead I saw a fist sized puddle of oil. It seemed to be directly under the rear of oil pan/front of bell housing. However it wasn't actively leaking when I was under there. Perhaps it was pooled up and got dumped when I jacked the car up? I can't think of anyplace where oil could gather in that volume, but who knows.
Filled up the radiator and started the car. Let it idle a solid 30 minutes. To my delight, there was No steam/smoke to be seen, although I was detecting the coolant smell but that could have been from yesterday's boil over.
Crawled under the car with a flashlight to see if I could spot a leaky head gasket, but instead I saw a fist sized puddle of oil. It seemed to be directly under the rear of oil pan/front of bell housing. However it wasn't actively leaking when I was under there. Perhaps it was pooled up and got dumped when I jacked the car up? I can't think of anyplace where oil could gather in that volume, but who knows.
You can borrow a coolant test kit from Autozone for free. Give them $80. When you bring the kit back, you get your $80 back. Takes about an hour or so to do a complete system test, and then you'll know for sure.
Don't worry about the volcano. That will happen. I'm a tech and seen it several times, the water boils when not under pressure and when you turn it off it stops circulating and boils over.
It could have been oil burn off from the valve covers. I would run it until the coolant circulates then drive it to burn off the excess oil. I actually power de-grease and power wash engines during re-seals to help alleviate this nuisance (oil burn off after repair). After driving it for a while check it and see how it's doing.
I would definitely recommend trying the cooling system pressure tester though. You can get them cheap at harbor freight. I have a snap on one and the quick service guys have the cheap harbor freight, mine was 10x as expensive and has less adapters..
I had a car I put together for a dude leak in basically the same spot (it was under number 3 or 5 on one side and 2 or 4 on the other) Does this car for some odd reason have perimeter bolt valve covers? The early style LS heads had a weird little divet/indention in the head surface and if you use MLS gaskets they will leak at that spot. The spot is offset from the center of the head and I can't remember the orientation whether it sits on cyl 3 or 5 on one side and 2 or 4 on the other. The car is too new to have come with those heads but weird **** happens, just like in my case. The dude gave me MLS gaskets and those heads and said the tuner told him that's what he needed. And they didn't work out, that's when I found out about the early heads and later gaskets. Probably not an issue in your situation but your description reminded me so much of when that happened.
It could have been oil burn off from the valve covers. I would run it until the coolant circulates then drive it to burn off the excess oil. I actually power de-grease and power wash engines during re-seals to help alleviate this nuisance (oil burn off after repair). After driving it for a while check it and see how it's doing.
I would definitely recommend trying the cooling system pressure tester though. You can get them cheap at harbor freight. I have a snap on one and the quick service guys have the cheap harbor freight, mine was 10x as expensive and has less adapters..
I had a car I put together for a dude leak in basically the same spot (it was under number 3 or 5 on one side and 2 or 4 on the other) Does this car for some odd reason have perimeter bolt valve covers? The early style LS heads had a weird little divet/indention in the head surface and if you use MLS gaskets they will leak at that spot. The spot is offset from the center of the head and I can't remember the orientation whether it sits on cyl 3 or 5 on one side and 2 or 4 on the other. The car is too new to have come with those heads but weird **** happens, just like in my case. The dude gave me MLS gaskets and those heads and said the tuner told him that's what he needed. And they didn't work out, that's when I found out about the early heads and later gaskets. Probably not an issue in your situation but your description reminded me so much of when that happened.
I had swapped out the plugs prior to being suspicious about a head gasket. None of them had the super clean look, but I wasn't putting each one under a microscope either. I'd like to think I would have noticed it. But who knows, I'm getting older and my mind is sometimes doing one thing while my body is on autopilot doing something else. 
Also I've been leary about putting pressure on the system as I'd hate to force coolant into a cylinder and have it pool up. And im to lazy to go back and pop the plugs back out. Those back two on the passenger side are a bitch! I should get a tester and do it right as you guys have suggested.
I'm finishing up a little bit of body work at the moment. Then I think I'll get any left over air out of the system and see what happens. I may just get lucky!
Also I've been leary about putting pressure on the system as I'd hate to force coolant into a cylinder and have it pool up. And im to lazy to go back and pop the plugs back out. Those back two on the passenger side are a bitch! I should get a tester and do it right as you guys have suggested.
I'm finishing up a little bit of body work at the moment. Then I think I'll get any left over air out of the system and see what happens. I may just get lucky!
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Typically if it spews coolant out the cap as you described with the cap off, its a bad head gasket. Which means you could also be or already have, superheated the engine. Could of cracked the heads, among other potential problems. Are you loosing coolant? It may not just leak, could be blowing out the exhaust as well. Make sure radiator is running as intended too. Check hoses while running and such. Scan for codes.