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condensation in the exhaust system

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nevets

nevets

Jedi Knight
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Kind of a silly question, but I'll ask anyway. When I first start my car from cold, a bit of liquid sprays from the exhaust. It seems to be dirty water, sooty actually, and can stain that which is behind the car. My theory is that as the exhaust system cools, condensation forms and accumulates in the low spot - that point just after the twin pipes exit the rear muffler, before the upward/rearward bend. Then the next time I start the car, the force of the exhaust casuses this dirty water to spray out the pipes. After a minute or less, it stops. Has anyone encountered this? I was considering drilling a tiny "weep hole" in each pipe right at the low point to allow the water to drain. Any comments would be appreciated, thanks.
 
This is a really handy feature of the cars so I wouldn't mess with it. Say you are showing your pride and joy at a car show and some knucklehead is making some disparaging remarks about your car or the motherland (infamous Lucas comments for example). Slip behind the wheel and wait for the opportune time when he/she is directly behind that exhaust pipe and then fire it up. Hopefully they are wearing light pants (concours judges should know this trick by now) .

Hip hip,
John
 
nevets,yes guys have been doing this [drilling weep holes]since forever,some even drill into the bottom of the muffler itself,does it work?well the water does run out,does it hurt?i think it would promote premature failure due to rust in that local area,are you stainless or mild steel? /ubbthreads/images/graemlins/smirk.gif
 
mild steel…but I am pleased to know that it's common, and John, I do like your suggestion of using this as a knucklehead deterrent!!! right up there with squirting people by twisting the windshield washer jets sidways. Ha!
 
Hey Nevets,

I got tired of spraying the "black water" on my garage floor (and anything else within 6 feet of the rear of the car) so I fashioned a very sophisticated device from a couple of wire coat hangers and a piece of an old bed sheet that I attach to the rear bumper before starting. It looks kind of like a mini-parachute and it catches all of the spray. After a minute or so I remove it, hang it out of the way in the garage, and I'm off!

Feel free to use my idea, just don't sell them to anyone else for money... /ubbthreads/images/graemlins/thumbsup.gif
 
In another post about water in the exhaust I said:
"It IS mostly water, as is the white "smoke" from the tail pipe. For every gallon of gasoline burned there is nearly a gallon of water produced as a by product. If the exhaust system is hot enough to completely turn the water to steam, you won't see much at the tail pipe. When the exhaust system is cold, nearly all of this water condenses on the cold metal & blows out the back as water. Since it carries carbon from inside the exhaust with it, a black mess blows out. If you live in a cold climate you will see a lot of steam as it condenses when it hits the cold air, even with the system hot."

A lot of water has to go "somewhere"
D
 
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