: Head Gasket?



mattyp
10-12-09, 11:39 PM
So I have a few questions, before I ask any question I will let you know that on a scale of 1-10 for being mechanically inclined I am a -5 :confused: So here is my problem, I have a 1999 STS seville with 57000 KM so thats about 36000 miles on it, I got it a little under a month ago and 2 weeks ago my check coolant level message came on, I checked and it was low, I thought hmm maybe it was low when I got it so I put some dex-cool in and never thought about it again until about 4 days and maybe 300 km's later the message came on again and it was down to the same level (2-3 inches from the full line) Now the car never over heats, it always stays in the 12 o'clock position, but I have now gone through 2 jugs of dex-cool in about 2000 km's. So my first question is, if it were the head gaskets, would it over heat or is it possible to not over heat and still have blown gaskets? second question is (it may sound stupid but some 2 bit "mechanic" told me this) would my car pass an e-test if it was burning dex-cool because of a blown head gasket? he said it wouldn't pass because of the chemicals that would come out of the tail pipe(my car passed the e-test fine), and he also said that you would smell preston from the tail pipe (i don't) I do however smell it close to the overflow reservoir like it was leaking there, I have never seen any drip marks on the ground and I check constantly, but this mechanic said that there is a plastic under the engine that could be catching it and stopping it from hitting the ground. I had this mechanic check for a leak and he said oh there was a small leak from a clamp on one of the hoses underneath and he replaced it, but it still loses prestone somewhere and I don't really trust him anymore, so I am asking here. Any help would be greatly appreciated

Submariner409
10-13-09, 11:04 AM
To rule out a failed head gasket either find a NAPA store or go online and locate a block test kit which checks the airspace over the coolant in the surge tank for combustion gasses. A radiator shop may also be able to perform the same test. Some large car parts sales houses will rent out one of these testers for a fee.

Basically the kit bubbles the surge tank air through a liquid chemical which changes color if combustion gas is present.

Your first searches for the coolant loss should be for leaks - and hope. ;)

Ranger
10-13-09, 12:03 PM
1. Yes it is possible to have a bad HG and not overheat (in the early stages).
2. Not sure, but I think you could pass.

mattyp
10-13-09, 12:40 PM
ok I will go to NAPA today and see if they can test it, Also I forgot to mention that when I remove the cap to the reservoir whether the engine is hot or cold air comes out, it does it a lot more when it is hot, but there is still some air that comes out when it is cold, is that a sign of a blown head gasket? Thanks for the responses guys

97EldoCoupe
10-13-09, 12:50 PM
With that low of miles your engine probably has the original coolant. This is very, very bad. I would be checking the coolant crossover gaskets for cracks and moisture/corrosion around them. That is where a lot of coolant loss problems start. But it is possible your head gaskets are on the way out.

Check for leaks and corrosion and moisture around all hoses, seals, and gaskets and do what Sub suggested.

mattyp
10-13-09, 01:16 PM
With that low of miles your engine probably has the original coolant. This is very, very bad. I would be checking the coolant crossover gaskets for cracks and moisture/corrosion around them. That is where a lot of coolant loss problems start. But it is possible your head gaskets are on the way out.

Check for leaks and corrosion and moisture around all hoses, seals, and gaskets and do what Sub suggested.

LOL call me stupid, but where are they?

tateos
10-13-09, 01:35 PM
The coolant crossover bolts to both cylinder heads on the drivers side - there are at least 6 gaskets or leak points

Submariner409
10-13-09, 02:22 PM
Coolant crossover - because the water pump is on the rear of the block, not the front - the most unholy murderous gasket changes you'll ever do.............

mattyp
10-13-09, 04:42 PM
Coolant crossover - because the water pump is on the rear of the block, not the front - the most unholy murderous gasket changes you'll ever do.............

lol that's nice to know, fortunately it won't be me doing it if that is the case, thanks a lot for the pics I will print them out and show them to the mechanic and see if he knows anything about it. I spoke to the mechanic and he said he thinks there is a lot of pressure and that it making the hoses leak and he is going to drain all of the prestone and re do everything. Hopefully that is the problem. He said he doesn't think it is the head gasket, but I don't know if I can trust him, I might just go and get a check done for $60 that will tell me for sure.

Submariner409
10-13-09, 05:06 PM
Your 1999 cooling system runs either 16 or 18 psi, not sure when the change to 18 came in. - check the Stant radiator cap replacement book at a local parts store.

mattyp
10-13-09, 09:04 PM
So I just pulled the rubber covers off of the spark plugs and looked down in and there was oil down around the spark plug in 2 of the 4 that I took off, I thought it was going to be prestone, but i stuck a paper towel down in and soaked some of it up and it smelled like oil and not prestone. I also forgot to mention that my prestone level goes down to about 2-3 inches from the top but never any lower than that.

Ranger
10-13-09, 10:15 PM
That IS oil. It seeps from around the O ring seals in the cam cover.

Wait a minute. What do you mean "goes down to about 2-3 inches from the top"? That's about where it is supposed to be. you are not filling it to the top, are you?

Submariner409
10-13-09, 10:28 PM
I'll bet he's filling it to the top, the engine heats up, the coolant expands and the coolant blows off. (Liquids are not compressible)

The coolant tank should be half full, cold. No more. The coolant needs a LOT of space to expand as it heats up. That's what pressurizes the system and raises the boiling point of the coolant.................

..............and the oil in the plug wells is normal, especially on a 10 year old engine. It's from the cam cover O-ring seals. They weep. Normal

tateos
10-13-09, 10:36 PM
Sounds like maybe a happy ending. Hooray! And thanks to Sub for posting the diagrams of the crossover.

mattyp
10-14-09, 01:03 AM
That IS oil. It seeps from around the O ring seals in the cam cover.

Wait a minute. What do you mean "goes down to about 2-3 inches from the top"? That's about where it is supposed to be. you are not filling it to the top, are you?

ok so what I mean for the 2-3 inches is there is a black top on the reservoir and it has an arrow that points down to the clearer part and says full cold, I thought that that meant it has to be at that level when cold. If not then why would the check coolant level message keep coming on? glad ro hear that the oil around the spark plugs is normal. I really appreciate all of the replies guys, thanks a ton

mattyp
10-14-09, 10:38 AM
So I had a mechanic take out the front 4 spark plugs to look at them and 2 of them had like a little white on them, he said that is normal because they are getting used and are due to be changed, and the other 2 were fine, no white on them. I'll explain how I am putting the fluid in a little better, so if you look at the reservoir, there is a black top and a clear bottom, on the black top there is and arrow that goes down to the clear part, so it points to where the black and the clear parts meet, and beside the arrow it says full cold, now when I fill it to there cold and drive around for a while the check coolant level comes on and when I check it it is 2 inches from where the clear and black meet, not from the cap.the the black has like 2 inches then it gets to the clear and the prestone is 2 inches down in the clear part of the reservoir, does that make any sense lol

kckranz
10-14-09, 10:51 AM
After you park the vehicle and return is the coolant level where the clear meets the black?

Two inches below the "black meets the clear" doesn't seem quite low enough to trigger that message on the DIC, especially since that leaves several inches of coolant over the sensor (the tank slopes downward from the wheel well to the engine).

kckranz
10-14-09, 10:56 AM
So I had a mechanic take out the front 4 spark plugs to look at them and 2 of them had like a little white on them, he said that is normal because they are getting used and are due to be changed

When due, replace spark plugs with ACDELCO Part # 41950 and no other.

Submariner409
10-14-09, 11:02 AM
Basically, the coolant level message should not come on as he is filling the surge tank correctly. These tank level sensors are known to trip false messages and the first check is to pull and clean the connector at the bottom of the tank. If that doesn't work and you are good about checking your engine fluid levels you could simply jump the harness connector with a 3kOhm resistor from Radio Shack to fool the system. Or, go on Amazon and look for a surge tank. I just got one, a GM factory replacement unit, for my 2002 for $65, shipped. That's less than half the dealer price. The tanks come with the level sensor.

mattyp, does your tank have a purge line - a 5/8" hose which runs from the nipple at the top side of the tank down to a nipple/bolt on the water pump cover housing ? This line constantly pisses coolant back to the tank in order to purge air and gasses from the system. With the car cold, remove the tank cap. Remove the hose from the tank nipple and hold it in the tank neck. Have an assistant start the car normally. Does a steady stream of coolant flow from the hose ?? It may spit and bubble for a second, but a steady stream should flow. If not then you need to clean out the hose and both nipples. The metal one may take a careful drill application due to hard deposits. You may have a trapped air bubble somewhere in the system and that could cause the strange coolant level change because the coolant should come UP in the surge tank with temperature, not DOWN.

mattyp
10-14-09, 11:54 AM
After you park the vehicle and return is the coolant level where the clear meets the black?

Two inches below the "black meets the clear" doesn't seem quite low enough to trigger that message on the DIC, especially since that leaves several inches of coolant over the sensor (the tank slopes downward from the wheel well to the engine).

This morning I had the car running for about 20 minutes with the mechanic squeezing the radiator hose and he said when he would unscrew the cap while holding the rad hose he could feel air go through the hose. Also after about 10 minutes the level of the coolant went up to about 1 inch from the bottom of the black, then the needle in the dash went about 1/4 inch over the 12 o'clock position and the mechaninc told me to put the heater on so I did and the needle went back to the center position but all of the coolant in the reservoir dissapeared, it got sucked all back in and all I could see was a tiny bit of coolant down by where the hose pulls the coolant from the reservoir into the engine, and he said oh that's normal, but because it was low it pretty much drained the reservoir, then when I got in the car to drive home it did something it has never done before, the temperature of the heat blowing would go to cool when stopped and then heat up again when I got to about 70 km/h. Would that have anything to do with having low coolant?

mattyp
10-14-09, 12:16 PM
When due, replace spark plugs with ACDELCO Part # 41950 and no other.

ok thanks, if it isn't the head gasket that is finished then I will do that, but if it is then I think the dealer is getting the car back

mattyp
10-14-09, 12:23 PM
Basically, the coolant level message should not come on as he is filling the surge tank correctly. These tank level sensors are known to trip false messages and the first check is to pull and clean the connector at the bottom of the tank. If that doesn't work and you are good about checking your engine fluid levels you could simply jump the harness connector with a 3kOhm resistor from Radio Shack to fool the system. Or, go on Amazon and look for a surge tank. I just got one, a GM factory replacement unit, for my 2002 for $65, shipped. That's less than half the dealer price. The tanks come with the level sensor.

mattyp, does your tank have a purge line - a 5/8" hose which runs from the nipple at the top side of the tank down to a nipple/bolt on the water pump cover housing ? This line constantly pisses coolant back to the tank in order to purge air and gasses from the system. With the car cold, remove the tank cap. Remove the hose from the tank nipple and hold it in the tank neck. Have an assistant start the car normally. Does a steady stream of coolant flow from the hose ?? It may spit and bubble for a second, but a steady stream should flow. If not then you need to clean out the hose and both nipples. The metal one may take a careful drill application due to hard deposits. You may have a trapped air bubble somewhere in the system and that could cause the strange coolant level change because the coolant should come UP in the surge tank with temperature, not DOWN.

I am going to fill the reservoir to the proper place AGAIN :helpless: when the engine is cold then try this and let you know, but if I remember correctly I don't see any hose near the cap.

Ranger
10-14-09, 12:52 PM
So I had a mechanic take out the front 4 spark plugs to look at them and 2 of them had like a little white on them
White plugs are a sign of burning coolant.

Also after about 10 minutes the level of the coolant went up to about 1 inch from the bottom of the black, then the needle in the dash went about 1/4 inch over the 12 o'clock position and the mechaninc told me to put the heater on so I did and the needle went back to the center position
Another bad sign.

then when I got in the car to drive home it did something it has never done before, the temperature of the heat blowing would go to cool when stopped and then heat up again when I got to about 70 km/h. Would that have anything to do with having low coolant?
That is because there is air (or exhaust gases) in the cooling system. They work their way to the heater core and you loose heat. I'd have the coolant tested for the presence of exhaust gases. Hate to say it, but it is starting to sound like head gaskets.

mattyp
10-14-09, 01:03 PM
White plugs are a sign of burning coolant.

Another bad sign.

That is because there is air (or exhaust gases) in the cooling system. They work their way to the heater core and you loose heat. I'd have the coolant tested for the presence of exhaust gases. Hate to say it, but it is starting to sound like head gaskets.

hmm, the white in the spark plugs was just on the bottom on the little hook part and not on any other part of the plug. And would the cool air have anything to do with having low coolant levels?

Ranger
10-14-09, 01:21 PM
hmm, the white in the spark plugs was just on the bottom on the little hook part and not on any other part of the plug. And would the cool air have anything to do with having low coolant levels?
It could, depending on just how low. Not if there was any coolant in the surge tank. If it was empty, then yes it could.

mattyp
10-14-09, 01:41 PM
It could, depending on just how low. Not if there was any coolant in the surge tank. If it was empty, then yes it could.

ok, because when I turn the heater on it empties the reservoir to just a tiny bit in front of the hose at the bottom of the reservoir,this is the first time that it has ever done that too, so hopefully it is just from low coolant.

Ranger
10-14-09, 05:00 PM
No, turning the heater on has absolutely no affect on coolant level. All that does is turn on the blower. Coolant runs through the heater core at all times. Temperature is controlled by mixing cold (outside air).

mattyp
10-14-09, 09:31 PM
No, turning the heater on has absolutely no affect on coolant level. All that does is turn on the blower. Coolant runs through the heater core at all times. Temperature is controlled by mixing cold (outside air).

So I filled the coolant back up and it again doesn't go over the 12 o'clock position and it blows hot constantly now, so that must have been because the coolant was really low.

zonie77
10-15-09, 10:58 PM
Radiator shops do the exhaust gas test regularly and charge less for it. Find a radiator shop that has the kit and get the test done. Do not add antifreeze just before doing the test.

mattyp
10-16-09, 12:25 PM
So I took it to a garage this morning and they just called me and said that it wasn't my head gasket, but it was my heater core, they said it is leaking the prestone into my drivers side carpet, now the reason that I didn't noitice it is because there was a little leak in the door crease too so when it rained it would get wet and that was running down to the floor too. And I was told that the heater core was on the passenger side so when I checked the flooor for wetness it was dry so I said hmm can't be that. Anyway, he said it is going to cost about $925 with the piece and the work and the tax, he said it takes about 8 hours to change that. So I would like to thank everyone here for all of the great posts and all of the help, it is greatly appreciated.

Submariner409
10-16-09, 12:44 PM
RockAuto sells the core for $69, but the labor to change it is murder. I think you have to remove the whole front of the console and HVAC air distribution box. The standard labor time is 6 hours !

mattyp
10-16-09, 01:51 PM
RockAuto sells the core for $69, but the labor to change it is murder. I think you have to remove the whole front of the console and HVAC air distribution box. The standard labor time is 6 hours !

Hmm he said it would take 8 hours work, that is a big difference, and $100 cheaper for the part too, that's like close to $300 cheaper than what he is saying.

Submariner409
10-16-09, 02:31 PM
Standard labor times are based on a trained GM Tech. A local shop fixes everything from Silverados to Mercedes, so they will naturally be somewhat "slower", and part of their money is made from parts retail markup.

You're paying the $300 for your busted knuckles.............(discounting your own labor time).

mattyp
10-16-09, 03:44 PM
Standard labor times are based on a trained GM Tech. A local shop fixes everything from Silverados to Mercedes, so they will naturally be somewhat "slower", and part of their money is made from parts retail markup.

You're paying the $300 for your busted knuckles.............(discounting your own labor time).

the thing is he's also charging me $160 to diagnose the problem :crying:

Submariner409
10-16-09, 04:20 PM
:shocked2: If the diagnosing shop gets the job, IMO they should eat the diagnosis time. That means you're looking at over a grand to replace a heater core.

According to Alldata the core is $120, dealer, and the labor time is 5.9 hours. At $90/hour that's ~$540 + 120 + tax/disposal = $675.

mikelawson
10-17-09, 12:22 PM
Replacing the heater core is definitely more than a 6 hour job. I'm pretty good at beating standard labor times. but the STS I had to do took me almost 9 hours. The heat distribution box stays in the car, but the entire dash and console has to be removed. If your total is 975, then I'd say you won't find it much cheaper and most mechanics won't eat the diagnostic cost since they did have to spend time looking at your car to determine the problem vs you going there and telling them a heater core needed replaced. I think they should have charged less than 100, so 160 is a little high.

Mike

mattyp
10-19-09, 06:43 PM
So I went to a GM dealer and got quoted at 6.5 hours work and the part was $135 for a total of $850 including $50 misc charges and that's if "everything goes well" whatever the heck that means

mattyp
10-19-09, 06:53 PM
:shocked2: If the diagnosing shop gets the job, IMO they should eat the diagnosis time. That means you're looking at over a grand to replace a heater core.

According to Alldata the core is $120, dealer, and the labor time is 5.9 hours. At $90/hour that's ~$540 + 120 + tax/disposal = $675.

I thought the same thing too, but when I got there and it was actually $176 to diagnose and plus $977 to fix I said well I'll take it home and let you know, needless to say they will not ever make another penny off of me.