6.0 engine excessive exhaust moisture?
12-24-2015, 10:27 PM
#1
Teching In
Thread Starter
Join Date: Jun 2008
Location: Champlain, NY
Posts: 14
Likes: 0
Received 0 Likes
on
0 Posts
6.0 engine excessive exhaust moisture? Recently bought a 2002 Chevy 2WD 3500 dually truck with 6.0 and 4l80E trans. Plan on using the engine for a streetrod and part the rest, the truck has 85K miles.
It appears that the moisture out of the tail pipe is excessive (to me anyway). The moisture only appears after the engine warms up, zero moisture at start up after setting overnight or longer. No DTC codes, no pending codes, no history codes and PCM I/M readiness is complete, engine runs great, oil is clean, anti-freeze is full and clean and the moisture does not smell like anti-freeze.
From what I understand the 6.0 has a dry intake so coolant leaks via the intake can't happen. The truck sat for a period and is not on the road so I considered the possibility that the muffler or exhaust may have condensation built up inside? Haven't checked the spark plugs yet...but since it runs great and smoothly haven't bothered.
Has me puzzled, engine will be gone over once I have it out...but wondering if anyone has experienced excessive smoke with a 6.0 engine. It's winter up here but been in the 50's.
It appears that the moisture out of the tail pipe is excessive (to me anyway). The moisture only appears after the engine warms up, zero moisture at start up after setting overnight or longer. No DTC codes, no pending codes, no history codes and PCM I/M readiness is complete, engine runs great, oil is clean, anti-freeze is full and clean and the moisture does not smell like anti-freeze.
From what I understand the 6.0 has a dry intake so coolant leaks via the intake can't happen. The truck sat for a period and is not on the road so I considered the possibility that the muffler or exhaust may have condensation built up inside? Haven't checked the spark plugs yet...but since it runs great and smoothly haven't bothered.
Has me puzzled, engine will be gone over once I have it out...but wondering if anyone has experienced excessive smoke with a 6.0 engine. It's winter up here but been in the 50's.
12-25-2015, 02:42 AM
#2
The engine pull in lots of air, Lots of water (humidity) in the air and it has to go somewhere. You will see more when the motor/exhaust system is cold, When the exhaust is cold it will allow the moisture to condensate before it comes out of the tail pipe. After the exhaust system is warmed up you will see less water but there will still be some, The rest just stays in vapor form. (some people think it's smoke lol)
12-25-2015, 07:57 AM
#3
Teching In
Thread Starter
Join Date: Jun 2008
Location: Champlain, NY
Posts: 14
Likes: 0
Received 0 Likes
on
0 Posts
LLLosingit
Thanks for the response...my situation is just the opposite. Minimal smoke when first started and warming up, when warm the smoke appears.
Have a lot of experience with for example the 4.3 Chevy engine with bad head gaskets on the rear passenger side. The engine would start, immediately smoke from the water in the cylinder and run rough until the water cleared out. With a leaking head gasket the water would seep into the cylinder when the motor was shut down as pressure pushed coolant past the gasket.
In this case, the 6.0 starts fine, runs fine, no codes and the vapor only increases when engine basically goes to closed loop. Again, no smell of anti-freeze...smells like your typical newer vehicle exhaust. Could pull the plugs to look for a steam bleached one (and probably will later)...but it runs normal through all ranges and suspect that inspection won't show anything anyway. Maybe I'm just being too critical....
Think I need to sneak it down the road a couple of times to flush out the exhaust system. Since the engine is coming out anyway...is there any specific gasket problem with the 6.0 engine?
Thanks
Thanks for the response...my situation is just the opposite. Minimal smoke when first started and warming up, when warm the smoke appears.
Have a lot of experience with for example the 4.3 Chevy engine with bad head gaskets on the rear passenger side. The engine would start, immediately smoke from the water in the cylinder and run rough until the water cleared out. With a leaking head gasket the water would seep into the cylinder when the motor was shut down as pressure pushed coolant past the gasket.
In this case, the 6.0 starts fine, runs fine, no codes and the vapor only increases when engine basically goes to closed loop. Again, no smell of anti-freeze...smells like your typical newer vehicle exhaust. Could pull the plugs to look for a steam bleached one (and probably will later)...but it runs normal through all ranges and suspect that inspection won't show anything anyway. Maybe I'm just being too critical....
Think I need to sneak it down the road a couple of times to flush out the exhaust system. Since the engine is coming out anyway...is there any specific gasket problem with the 6.0 engine?
Thanks
12-25-2015, 08:31 AM
#4
Water is a normal part of the combustion process and you'll get slightly more of it in closed loop as the engine starts running efficiently. (But not a noticeable amount.) The amount of water in the exhaust is dependent on how much gas you are burning. As pointed out above, water usually comes out as invisible vapor.
I expect the reason you see a lot of water deals with temperature. More water will condense out at cooler temperatures. In closed loop, the temperature off the exhaust will drop considerably, causing more water to condense. The ambient temperatures of the season also will cause more condensation. Lastly, those super-long pipes on your extra-large dualy beast give more opportunity for water to cool and condense before it comes out the pipe. (Acting almost like a stil.)
I expect the reason you see a lot of water deals with temperature. More water will condense out at cooler temperatures. In closed loop, the temperature off the exhaust will drop considerably, causing more water to condense. The ambient temperatures of the season also will cause more condensation. Lastly, those super-long pipes on your extra-large dualy beast give more opportunity for water to cool and condense before it comes out the pipe. (Acting almost like a stil.)
12-25-2015, 10:19 AM
#5
Very possible the exhaust has a bunch of water hiding in it from short drives and sitting. It tends to come out once the exhaust is heated up and starts to evaporate. If it doesn't smell like coolant I'm sure that is all it is. Also some muffler designs tend to trap water and if the drain holes are blocked you will notice this.
12-26-2015, 06:47 PM
#6
water (vapor) is produced by the catalytic converter from the exhaust gas from the combustion process.
it is said that if correct combustion is happening and the catalytic converters are working 100% you get around 1 gallon of water produced per gallon of gasoline burned.
you are seeing liquid water because as the exhaust pipe cools (trucks have longer exhaust pipe and usually larger muffler) the water vapor condenses to liquid. the 6.0L being on the larger side.... in a 3500hd dually will always be under a decent load thus pulling in lots of air -> more combustion -> more water vapor.
the 8.1L in my 2006 2500hd produces a huge vapor cloud on cold mornings while driving.
http://jg2090.newsvine.com/_news/200...-pounds-of-co2
2C8H18 + 25O2 → 16CO2 + 18H2O + heat
it is said that if correct combustion is happening and the catalytic converters are working 100% you get around 1 gallon of water produced per gallon of gasoline burned.
you are seeing liquid water because as the exhaust pipe cools (trucks have longer exhaust pipe and usually larger muffler) the water vapor condenses to liquid. the 6.0L being on the larger side.... in a 3500hd dually will always be under a decent load thus pulling in lots of air -> more combustion -> more water vapor.
the 8.1L in my 2006 2500hd produces a huge vapor cloud on cold mornings while driving.
http://jg2090.newsvine.com/_news/200...-pounds-of-co2
2C8H18 + 25O2 → 16CO2 + 18H2O + heat
12-26-2015, 07:01 PM
#7
Lots of water (humidity) in the air and it has to go somewhere. You will see more when the motor/exhaust system is cold, When the exhaust is cold it will allow the moisture to condensate before it comes out of the tail pipe. After the exhaust system is warmed up you will see less water but there will still be some, The rest just stays in vapor form.