So I did some driving around today with no signs of problems, no smoke noticed, no overheating, engine running normal.
After I got home I decided to check the oil level. What I found was that the oil on the dipstick looks a little "thin". Now the oil is only about 1 month old so it should look normal.
This got me suspicious so I ran the engine and from the tailpipe I could see the white smoke. Not a huge amount but definitely noticeable.
So of course my assumption is that the head gasket is blown.
Any other opinions?
I'm new to old cars so I don't have much experience with this type of problem.
What is the best method to diagnosing this for sure, other than removing the head?
In the meantime it's just going to sit so I don't cause any (more) damage.
Any help is appreciated!
Thanks.
Blown head gasket?
Not sure what thin oil looks like. If it's a month old, average driving, it should look clear and gold, up to the full line on the stick.
A major crack in the head usually pumps white smoke out the exhaust like a fighter plane going down and the oil turns milky. That and the temp goes up from the coolant going where it shouldn't.
Depending upon outside air temperature, sometimes water vapor in the exhaust system takes awhile to steam out, or keeps steaming. I had a head or head gasket with a tiny crack that used to steam until engine heat expanded things to stop it. Dumb as it sounds, coolant level drop was almost zero, oil stayed clear, so I drove it that way for years.
You can monitor the above items: oil clarity, level, coolant level, temperature. Smell under the hood after a drive for steamy, look for any, as well as how much white smoke, when, for how long is coming out the tail pipe. Pull the plugs to see what they look like.
Experts here may say otherwise, but I think if there's clear oil in it, coolant full, temp within limits, no loud noises, you can drive it to see what's happening without fear of doing major damage to anything.
A major crack in the head usually pumps white smoke out the exhaust like a fighter plane going down and the oil turns milky. That and the temp goes up from the coolant going where it shouldn't.
Depending upon outside air temperature, sometimes water vapor in the exhaust system takes awhile to steam out, or keeps steaming. I had a head or head gasket with a tiny crack that used to steam until engine heat expanded things to stop it. Dumb as it sounds, coolant level drop was almost zero, oil stayed clear, so I drove it that way for years.
You can monitor the above items: oil clarity, level, coolant level, temperature. Smell under the hood after a drive for steamy, look for any, as well as how much white smoke, when, for how long is coming out the tail pipe. Pull the plugs to see what they look like.
Experts here may say otherwise, but I think if there's clear oil in it, coolant full, temp within limits, no loud noises, you can drive it to see what's happening without fear of doing major damage to anything.
Ok, so maybe I was a bit paranoid. After letting the engine warm up for about 2-3min. the smoke goes away. I drove few a few miles and nothing more out the exhaust. javascript:emoticon(':D') And as far as the "thin" oil, that could just be my imagination.
What I meant by thin is that it looks watery. What I was thinking is that the coolant is getting into the oil and thinning it.
I didn't think the head was cracked, that would definitely show worse signs like you said, but I was afraid of a blown gasket.
So, my question now is: does this white/gray smoke at the first few minutes of cold engine really happen just from condensation or is it a sign of something more?
Dave
What I meant by thin is that it looks watery. What I was thinking is that the coolant is getting into the oil and thinning it.
I didn't think the head was cracked, that would definitely show worse signs like you said, but I was afraid of a blown gasket.
So, my question now is: does this white/gray smoke at the first few minutes of cold engine really happen just from condensation or is it a sign of something more?
Dave
-
tacomagabe
- Posts: 89
- Joined: Tue Jan 06, 2009 7:36 pm
- Location: Tacoma wa
I always thought more visable smoke out the tail pipe when it's cold was just a little richer fuel mixture til the engine warms up. Could be wrong. In my exp when you have tons of white smoke and bad gas milage it can be that an o2 sensor has failed and you are running rich.
Gabe B.
1981 528i
1995 525it
1981 528i
1995 525it
All exhausts swirl white stuff in winter. If you take a good whiff of whatever's coming out the tail pipe, coolant vs. petrol is different and usually obvious. If oil and coolant are mixing, you get cloudy, milky, foamy. Try it in a glass on the bench.
I like the O2 sensor suggestion. I'm going to replace it; once I rent the wrench, chains and elephant it apparently takes to remove.
Besides watching STP drip slowly, SAE 30 drip faster off the end of the dip stick ( different thickness, viscosity ), nice new oil is usually so clear, clean, it's hard to see on the stick.
Valve guides in the M30 are plastic and known to get leaky after 30,000 miles. That translates to a plume on start up, no big deal. Finally, there's idling smoke and then there's the more serious ( pistons / rings ) kind that fogs under hard acceleration.
I know from paranoid, getting used to a new old car. Again, if the oil is new, full, coolant level in reservoir stays up and the temp needle sits around the middle mark, no big noises,...drive it.
I like the O2 sensor suggestion. I'm going to replace it; once I rent the wrench, chains and elephant it apparently takes to remove.
Besides watching STP drip slowly, SAE 30 drip faster off the end of the dip stick ( different thickness, viscosity ), nice new oil is usually so clear, clean, it's hard to see on the stick.
Valve guides in the M30 are plastic and known to get leaky after 30,000 miles. That translates to a plume on start up, no big deal. Finally, there's idling smoke and then there's the more serious ( pistons / rings ) kind that fogs under hard acceleration.
I know from paranoid, getting used to a new old car. Again, if the oil is new, full, coolant level in reservoir stays up and the temp needle sits around the middle mark, no big noises,...drive it.
Thanks guys for rationalizing through this and calming my fears.
What is said makes sense to me, I plan to drive it and keep a good eye on what's happening.
Did I ever mention how much I value a forum like this that is free of immature irresponsible speculative self indulging verbal masturbation?
A huge improvement over many others I have seen.....
But then my previous cars were "ricer" sports cars so I guess it goes with the territory. Anyway, thanks.
Dave
What is said makes sense to me, I plan to drive it and keep a good eye on what's happening.
Did I ever mention how much I value a forum like this that is free of immature irresponsible speculative self indulging verbal masturbation?
A huge improvement over many others I have seen.....
But then my previous cars were "ricer" sports cars so I guess it goes with the territory. Anyway, thanks.
Dave