Smoke or steam ?
Discussion
Guys on the motorway today 5 miles into the trip doing about 70 I had to slow down and then put my foot down about 75% to speed up again and going from off throttle to on throttle I got what I thought was condensation very briefly and it went high up after exiting the exhaust - I dont think it was oil as it dispersed quickly and went above the car.
It doesnt do it all the time but did it a few times - is this a sign of impending doom or just a result of the cold ?
Its a Subaru 3.0 H6 engine Cheers
It doesnt do it all the time but did it a few times - is this a sign of impending doom or just a result of the cold ?
Its a Subaru 3.0 H6 engine Cheers
And 5miles in, the bulk of the exhaust system will be still cool esp. at the tailpipe end, so the gases make it out of the far end readily condensing/cool enough to condense.
It's why you get plumes of water vapour from cars in cool weather long after you'd notice it in summer.
NB burning a gallon of petrol makes about 2galls of water - or as steam at 100degC- about 3400gals IIRC there's about 1700X expansion from water to vapour at the boiling point, and all teh intke air is alos expanded in proportion to the wasted exhaust heat, too.
Seeing clouds on a cool day really shouldn't surprise, but there are good reasons for it and does not indicate something wrong
It's why you get plumes of water vapour from cars in cool weather long after you'd notice it in summer.
NB burning a gallon of petrol makes about 2galls of water - or as steam at 100degC- about 3400gals IIRC there's about 1700X expansion from water to vapour at the boiling point, and all teh intke air is alos expanded in proportion to the wasted exhaust heat, too.
Seeing clouds on a cool day really shouldn't surprise, but there are good reasons for it and does not indicate something wrong
Huff said:
And 5miles in, the bulk of the exhaust system will be still cool esp. at the tailpipe end, so the gases make it out of the far end readily condensing/cool enough to condense.
It's why you get plumes of water vapour from cars in cool weather long after you'd notice it in summer.
NB burning a gallon of petrol makes about 2galls of water - or as steam at 100degC- about 3400gals IIRC there's about 1700X expansion from water to vapour at the boiling point, and all teh intke air is alos expanded in proportion to the wasted exhaust heat, too.
Seeing clouds on a cool day really shouldn't surprise, but there are good reasons for it and does not indicate something wrong
Also the reason why cars used only for short journeys go through exhausts faster than those used for long runs as the exhaust doesn't get hot enough to boil off the water so they rot from inside.It's why you get plumes of water vapour from cars in cool weather long after you'd notice it in summer.
NB burning a gallon of petrol makes about 2galls of water - or as steam at 100degC- about 3400gals IIRC there's about 1700X expansion from water to vapour at the boiling point, and all teh intke air is alos expanded in proportion to the wasted exhaust heat, too.
Seeing clouds on a cool day really shouldn't surprise, but there are good reasons for it and does not indicate something wrong
Keep an eye on your coolant & oil levels & if nothing's happening to them don't worry about it.
Bear in mind that at this time of year mayo is not unusual in oil filler caps esp on short run cars & again down to water not boiling off. Mayo is often cited as a surefire diagnosis of HGF. It isn't & I wonder how many have had their trousers pulled down by the unscrupulous for unnecessary work.
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