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Is a blown head gasket the end of the line??

56K views 394 replies 41 participants last post by  tonyisok 
#1 ·
I'm trying not to panic here, I'll take a deep breath...

I bought this car used with 70,000 miles last June. Today I checked my coolant for the first time since the end of last summer. When I had the car serviced last year in August by my indy, they showed me that the coolant was at a good level. They also pointed out to me that the thermostat looked new, and that there was some evidence of past leaks. I foolishly didn't think anything of it from that point.

I began noticing that the car seemed to be burning oil, but figured at 70,000 miles that was normal. I saw some tiny amounts of odd, milky residue in the early winter on the oil cap, but concluded that this was probably just condensation.

Today this all changed when I saw that I had almost no coolant, the bobber's top was just inside the filler neck. When I checked the oil dipstick, I saw the same milky, chocolately residue that I remembered seeing on the oil filter cap a while ago. I still don't have white smoke or sweet smelling exhaust.

How likely is this to be a head gasket issue caused by overheating from the previous owner? Can some head gasket leaks be worse than others? Can they grow and become worse and worse over time?

Finally, tell me straight. I'm still making payments on the car, I don't intend to sell her ever. How long do I have before she dies if I do nothing? Do I have any time to wait before I can get it fixed? Is it even worth it to fix?

I have had no low coolant lights, so for the moment I'm gonna fill her up with 50/50 BMW coolant/distilled water.

I realize rather abundantly now that I should have done a good PPI before buying the car, lesson sadly learned... :banghead:

Thanks for your help!
 
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#3 ·
It could be head gasket, but...

If prior owner had overheated it and blown headgasket, you'd have had symptoms...like a sputtery start until whatever coolant has been burned out...eventually getting worse until you know it's head gasket.

So you notice smell of coolant in exhaust...(just put your nose by tailpipe for like 5 mins or so...sure all your problems will disappear quietly! LOL)? I had when I blew my HG in E36...coz I drove like 15 miles like an idiot.

Lack of driving in winter, condensation as you say, leads to most of what you've described. You say you're burning oil, but you could just be losing it. Have you looked for oil leaks after removing underskirt?

Low coolant could also be other things like another slow leak/seep/weeping somewhere. Many here hunt leaks all the time...many times don't find them coz they're not underneath car while it's running at Op temp. Coolant could've leaked from 50 different places...not necessarily a head gasket.

So, have you overheated it? Have you checked carefully for leaks of either oil or coolant (might as well find the PS fluid leaks too while you're looking)?

If it is headgasket, still doesn't mean it's the end...just could be an expensive lesson...if it is cylinder head, a more expensive lesson. Either could be a really frustrating but otherwise first time DIY, but it'd take a while and you'll want to recruit knowledgeable friends with beer to help...a lot!

So, not the end of anything...unless you want it to be. Get fluids up to proper level. Take for long drive and keep an eye on things...actually, check that. First get to proper level, drive locally for a day or two to see what's up...if no leaks, get her out on highway for a nice 'cleaning.'

HTH,

Doug
 
#5 ·
do evrything Doug says but i'd also drain the oil and take a look at it...if its milky then we have a problem.
Milky I've heard coming from condensation...cars sitting or not getting driven...new gas supply with bad gas. The cappucino color, I've heard is just a film from the oil...

Oil change a good idea...but first get a sense of where your fluids are going. Coolant that hasn't been checked since August could be a million things (meaning many leaking sources)--therm/waterpump gaskets/o-rings...bleed screw, hoses, sensor, ET...list goes on of course. First find this leak...and search while at Op temp without underskirt on...unless you see leak with underskirt on.

Assume the simplest first--coolant leak and oil drips...go from there...don't panic...drink, find woman, relax!

D
 
#7 ·
Thanks for all the tips guys! :thumbup:

I drove to the dealer and they were kind enough to top off my coolant for free. In the process I got a shock when I saw that when the mechanic took off the coolant cap, the bobber was almost at the correct level! :yikes: I then realized that I'd been really dumb and checked the coolant after the car had sat for three hours, since I kept hearing that you shouldn't check the coolant right after engine shutoff. :banghead:

Just in case I'm in denial though, this weekend I'll do a thorough underhood search for leaks.
 
#9 ·
I think you heard right about checking coolant level when engine is cool. You also don't generally add a cool liquid to a hot engine...but a drop or two couldn't hurt...just don't ever dump a significant amount in when hot...is what I've heard and believe.

You also don't generally open it up hot so you don't get sprayed with hot coolant. You still need to check coolant levels when cool and if you keep it between min and max, easier to see a change. Once you get to full, you never know how much overfull you are.

Closely watch oil levels too...and see what you can figure out about looking into that underskirt. I know some cars have the support built into that panel. On mine, just a plastic skirt with 6 screws...simple. I know others have a much more there...must be a PITB anytime you want to do something yourself underneath. Also, wouldn't bolts for things like that be one-time-use only? I'm just thinking if it's a structural part of the car...wouldn't bolts need to be replaced (technically) every time that panel is off. Mine has a triangle of steel rods...and seems sufficient. Don't know if they were trying to stiffen things further, or maybe knock off two birds with one stone building underskirt and support together.

Anyway, OP, keep a close eye on things. You start drinking yet? LOL

D
 
#10 ·
have it inspected immediately ... replacing all this stuff after it breaks is a massive hole in your pocket. This recently happened to me. I bought an 01 330xi w 93k miles and after a month I overheated and the cylinder head melted and needed to be remachined and I needed a new oversized head gasket which the total job including remaching cost be about 2,500 ... don't take any risks ... it was my fault for by the car as is even with a mechanic

however, DO NOT TAKE CHANCES ... you will thank yourself by getting this checked out ahead of time ... DO NOT LET IT OVERHEAT
 
#13 ·
I'll bring this one back from the dead a bit...

My girlfriend's car (2001 325i w/ 150k) had a whole host of issues when i went to go pick it up after getting new tires installed...

- low coolant light
- apparently no oil in the dipstick, so the tire shop added a quart of oil
- they said there was a milky residue on the cap

This sounds to me like a failing or failed headgasket. However, there is no burning oil smell or burning coolant smell. So, I am thinking of letting the dealer look at it to see what they think is wrong. Then, I'll probably be the one to do the work.
 
#17 ·
Like the others said our cars often have condensation in the oil, especially if you are crazy enough to change it every 15k miles as per BMW service indicators.

I notiicec you used an extractor to do an oil change. Oil is lighter then water so if there is any condensation it will be at the bottom of the pan. Go for a good drive get it it nice and hot and drai. It by the plug , ope. It up and let it dran as long as you can.

You may be ok. These motors are tough, you have to overheat pretty good to blow a head gasket.

It is not a Chevy Cavalier that blows head gasket every 2yrs :)
 
#18 ·
So the plot thickens... I just drained the oil and had over 6 qts in the drain pan. The guy at the tire shop said the dip stick was dry so he added a quart. Now, if the dip stick was dry and he added a quart, then shouldn't I have had a lot less than 6 quarts of oil when I drained it?

I changed the filter and threw in 7 qts of synthetic Mobil 1 0w-40.
 
#19 ·
Not necessarily. If it was really dry and he added a qt., it might have brought it up to about the bottom notch...or 1 qt. low...6 qts.

But, you should check stuff like this...nothing personal...but verify/monitor issues when they're known. I know I'm leaking PS fluid...so I check every day...and probably check oil once a week if not more...coolant, at least once a month.

What's curious, though, is why gf's car didn't signal to her that she was low on oil...at only 5 qts., the oil level sensor should have triggered it. Next time you do an oil change for her, you might replace that oil level sensor, and in the meanwhile, knowing she got low on oil, make sure you or her check the oil regularly. Running low on oil is not good at all. She might have a leak, might be burning oil...but you should figure it out. If only leaking, you can live with that as long as you replace it...burning it...might be a different issue and something that will need attention. That's not 'in evidence' yet, but the oil test should help you figure that out.

Did you save some of the oil you drained to send it in for analysis?

Doug
 
#20 · (Edited)
I think dip sticks are very inaccurate when a car has been run. Unless it was checked on a cold engine, I never trust what that dipstick says. Mine looks dry if I pull the dip stick out after a drive, meanwhile the system is full. Thats cause the oil still hasnt drained back down into the pan. Any dumb shade tree mechanic would call that dry and overfill the system.
 
#42 · (Edited)
I think they're very accurate, but agree that it takes a while for the oil to return to drain pan.

If I measure mine at five minutes after shut down, I know it will be low (still within range, but apparently down at least a 1/2 qt.)...an hour later, pretty close to full, but in the a.m., it will be at the same level it was when I drained it, shook off the last drops, and refilled with 6.9 qts....maybe just a tad lower now.

But you fill it cold and if you wait long enough after that, it should be right at the bottom of the top notch...give or take just a tiny bit.

If you fill oil based on the dipstick, you're assuming the dipstick/guidetube are correct...and they're not always...usually I'm sure they are, but mine wasn't!
 
#22 ·
As for the oil analysis, I just ordered the free kit today. It will be a few weeks before I can send it out for analysis. In addition to monitoring the dipstick when hot and cold, I will also monitor the cap for the residue (milky coolant mix) he says he saw. We'll see how it goes.
 
#28 ·
So the car had no real issues and then sat for 3 days while we were snowboarding in PA. The ambient temperatures got down to the negatives. Then, Monday morning after a cold start in 9F ambient temps, the car immediately overheated with the air on at 91F and full blast trying to defog/defrost the glass. We shut the car off and limped the car home. The car smokes now, but its not oil and i couldnt check the coolant at that time since the coolant temp indicator was on H.

What do you guys think? Is the headgasket gone now? Or is it another leak in the system that somehow killed more coolant in 3 days than it used to in 3 months?? Thoughts?
 
#30 ·
So I checked the coolant level today and it seems full. I am thinking either a thermostat that is stuck closed or some other clog in the cooling system. Where should I start? What's the easiest place to check first?

I thought about pulling the plugs to see if there is residue on them, but they're not exactly the easiest things to get to (with those plastic covers and all...)

Any and all suggestions are appreciated. Thanks!
 
#31 ·
You said the car immediately overheated after start up in 9°F = (-12.8°C) outside temp and being NOT driven for 3 days. :hmm:

The car usually takes up to 15-20 minutes for the motor to JUST come to almost normal temps at that low of a outside temp. It would take at least 25 minutes for the thermostat to open.

I suspect you have a sensor gone bad situation. The car will NOT overheat if the system has coolant in it, even if its below the lever. But since you said yours is up to level, I suspect your water temp sensor (coolant temp sensor) has gone bad, OR its not bad but simply picking up the reading from the air bubbles in the system from incorrect bleeding.

Run a compression test so that you can eliminate the "blown head gasket" theory once and for all.

If there are no leaks and coolant stays in the system up to level , given thermostat is good, WP works and headgasket is good, the car would NOT overheat EVER under normal driving circumstances. Even if the gauge goes to red, the car would NOT overheat(it picks up a reading from a very hot air bubble in the system and throws the gauge off the scale).

Its theoretically impossible.
 
#32 ·
So I'm still working on getting a compression tester, but i went ahead and pulled the plugs. 5 of the 6 seemed to be black and covered in gasoline (probably from all the cold starts without letting the engine get to running temperature). The last plug was also black, but was very dry and was very hard to remove from the cylinder head. I'm not sure what that means at the moment, but I figured I'd put it out there.
 
#33 ·
I should also mention that the car smokes quite a bit at idle now. It doesn't really smell like any one substance though. Not burning oil, not gasoline, and not really coolant either. Again, a compression test will hopefully yield some information as to what's broken.
 
#36 ·
While I'm working on getting the compression tester, do you guys think it makes sense to do a complete flush of the coolant system to check for clogs and stuff? Is there an easy DIY way to check for a clogged radiator or expansion tank or something?

If the compression test shows that its good to go, I am thinking of draining everything, pulling the radiator, expansion tank, hoses, pump, and thermostat and giving them a thorough inspection prior to replacement.
 
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