Water from one tailpipe

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Yes, it's normal and it's also why you want to drive your car at highway speed for half an hour at least once a week - to burn the condensate out of the engine and exhaust system.

This sounds like something my step-father would tell me but also like is has no basis in reality.

Because your stepfather clearly understands more about cars than you'd ever know, even if you lived another hundred years.

PP is right, there is no condensation in the engine and exhaust system when the car is not running. When the engine is turned off, it pumps at least one full cycle to take in fresh air and expel exhaust. The residual heat in the exhaust prevents any water vapor from condensing. By the time the exhaust cools, the air in the exhaust system has reached the same humidity as ambient air.

Huh?

Do you even chemistry, bro? WTH are you talking about?



When gasoline is burned, the largest by-product produced is water vapor. Gasoline is a hydrocarbon. When it burns, the chemical reaction from that oxidation strips the hydrogen and carbon atoms apart, releasing heat energy. Most of these bond with oxygen atoms, producing carbon dioxide and ..... wait for it .... the stuff made from two hydrogen atoms and one oxygen atom.... called....... WATER !!!!

Water is THE biggest component of car exhaust.

When the exhaust system is cold, it condenses before it exits the system, turning back into water. After the exhaust system is fully warm, it remains a vapor all the way out the tailpipe. But water is constantly being produced whenever fuel is burned.


Do you not understand even basic junior high school chemistry, or what?

[Anonymous]

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:Yes, it's normal and it's also why you want to drive your car at highway speed for half an hour at least once a week - to burn the condensate out of the engine and exhaust system.

This sounds like something my step-father would tell me but also like is has no basis in reality.

Because your stepfather clearly understands more about cars than you'd ever know, even if you lived another hundred years.

PP is right, there is no condensation in the engine and exhaust system when the car is not running. When the engine is turned off, it pumps at least one full cycle to take in fresh air and expel exhaust. The residual heat in the exhaust prevents any water vapor from condensing. By the time the exhaust cools, the air in the exhaust system has reached the same humidity as ambient air.

Huh?

Do you even chemistry, bro? WTH are you talking about?



When gasoline is burned, the largest by-product produced is water vapor. Gasoline is a hydrocarbon. When it burns, the chemical reaction from that oxidation strips the hydrogen and carbon atoms apart, releasing heat energy. Most of these bond with oxygen atoms, producing carbon dioxide and ..... wait for it .... the stuff made from two hydrogen atoms and one oxygen atom.... called....... WATER !!!!

Water is THE biggest component of car exhaust.

When the exhaust system is cold, it condenses before it exits the system, turning back into water. After the exhaust system is fully warm, it remains a vapor all the way out the tailpipe. But water is constantly being produced whenever fuel is burned.


Do you not understand even basic junior high school chemistry, or what?

You are late to the discussion, I already described what you wrote here earlier in the thread. If the engine is not running, how does water vapor get in to the engine and exhaust that would necessitate running the engine for 30 minutes every week like the Pp recommends.

If the engine was turned off after normal driving there is no water vapor or moisture in the engine and exhaust beyond nominal levels, because as I described earlier and what you also described here, the water comes from the combustion.

I know you are jumping at the chance to sound smart, but you should read the thread first.

[Anonymous]

Water doesn't "get into the engine" Do you even understand how engines work?


The exhaust is largely water, because water is produced when liquid hydrocarbon fuels are burned. . When that water produced by that combustion condenses inside the exhaust system (because parts of it are still cold enough because it hasn't reached a "hot" temperature all the way to the tailpipe) it accumulates inside the exhaust, usually inside the muffler housing.

If you did nothing but short trips of a few miles, followed by a complete cool down, you're probably accumulating around a quart to half gallon of water in each of the mufflers, all the time, because it never gets hot enough to "cook" all the water out. So that water sits in the muffler, and rusts it out over time.


Getting up to highway speed and driving for 30-60 minutes every week or two gets the exhaust system hot enough to cook off all the accumulated water that gets created on short trips.



I've been working on cars for 26 years. I love it when people who don't even understand "how water gets in the engine" tell me I'm wrong.


Do you also tell your doctor how our organs work, too?

[Anonymous]

Exactly, water does not get into the engine except as water vapor from the combustion. You seem to think we disagree on this point. I am not the dumbass PP who claimed there is water in the engine. My point is there would not be any water in the engine.

Also, you are wrong that there would be a quart of water left in the muffler. All mufflers have a weep hole. Maybe the ones you worked on was clogged but it's there.

I have been working on cars for much longer than 26 years and have band built engines.

[Anonymous]

Water is the primary product of combustion? What about carbon monoxide?

[Anonymous]

Anonymous wrote:Water is the primary product of combustion? What about carbon monoxide?

There's usually more than 3 hydrogen atoms per carbon atom in most petroleum molecule chains. The exact number, bonding order, and chain shape depend on the compound itself, but the common theme is that there are far more hydrogen atoms than carbon, and when oxidized, there is far more H2O produced than any other compound, simply because of the abundance of H to begin with. Also, O has such a strong binding force that it will usually grab C in pairs, making CO2. CO is also produced, but only because all the available O has already been paired with H and C(paired) already. Only the O's without another O bind to C as a result of low thermal efficiency/incomplete combustion. They are a relatively small product of the process.

[Anonymous]

Anonymous wrote:Exactly, water does not get into the engine except as water vapor from the combustion. You seem to think we disagree on this point. I am not the dumbass PP who claimed there is water in the engine. My point is there would not be any water in the engine.

Also, you are wrong that there would be a quart of water left in the muffler. All mufflers have a weep hole. Maybe the ones you worked on was clogged but it's there.

I have been working on cars for much longer than 26 years and have band built engines.

I rebuild several engines a month. I probably do about two dozen a year. I've been an ASE Master since 1997. And if you've ever pulled the mufflers out of short-trip Subaru Outback or Forrester (notoriously) in the winter, you'd know to have a large catch basin ready when you separate the pipe.

[Anonymous]

Anonymous wrote:

Anonymous wrote:Exactly, water does not get into the engine except as water vapor from the combustion. You seem to think we disagree on this point. I am not the dumbass PP who claimed there is water in the engine. My point is there would not be any water in the engine.

Also, you are wrong that there would be a quart of water left in the muffler. All mufflers have a weep hole. Maybe the ones you worked on was clogged but it's there.

I have been working on cars for much longer than 26 years and have band built engines.

I rebuild several engines a month. I probably do about two dozen a year. I've been an ASE Master since 1997. And if you've ever pulled the mufflers out of short-trip Subaru Outback or Forrester (notoriously) in the winter, you'd know to have a large catch basin ready when you separate the pipe.

I don't know why the two of us are arguing about this, we are in agreement that 1) water vapor comes from combustion, and that 2) it condenses as it passes through a cold exhaust system that has not warmed up yet, and 3) it eventually cooks off once the exhaust system heats up.

My disagreement is with one of the previous PPs who claimed that cars needed to be driven for 30 minutes every week to get rid of moisture/water in the engine and exhaust. This is simply not true.

Maybe Subaru doesn't see fit to have weep holes in their exhaust, I've never owned one and never felt the desire for one. But it is a well known fact that mufflers typically have weep holes. You should know this as a tech.