Liquid Exhaust

[blitzkraig]

Ever since I got my Z back on the road I've noticed liquid coming out of the exhaust. I don't mean the occasional drip, I mean if I leave the car running in the same spot for 5 minutes a small black puddle will start forming from the spray. It doesn't smell like fuel, it's not clear like water (I'm not loosing coolant), and it's too thin to be oil. Any ideas on how to stop this??? It's made my Supertrapp muffler turn black with crap all over it and it's just driving me nuts!

[Inf]

I've been getting it too, but i've attributed that to the massive amount of oil being burned (about 1 quart every 400 miles).

[beandip]

It sounds like condensation in the exhaust plumbing being pushed out and collecting soot and driping down. Does this still happen after the car has been driven for a half an hour ? It really takes quite a while for the engine to completly warm up . Just because the temp gague shows normal temp, the oil and the block and head are not all up to temp. During this warm up time moisture is turned to steam and condences back to a liquid when it is cooled again , if the pipeing is cool it acts like a condenser and turns the moisture back to a liquid. The cooler air does the same thing . If the humidity is high the more it is noticed. you may just be aware of now since you just got it back up and running. You said that you were not leaking or missing any coolent .:classic:

[280zx Fever]

your getting watter into the combustion chamber id say.

[Zs-ondabrain]

what is the moisture or humidity like in your area, especially at night?

POP CAN THEORY, When the temperature outside is hotter than that inside ( a sweatting soda can )

in-other-words, when you shut the car off after heating the exhaust system sufficiantly, the moisture from the outside air collects all through out the exhaust system.

Mean while, it collects soot that is all through out the pipping, and deposits it in the form of spray and or a constant dripping.

It wont smell like fuel or oil, its thicker than water and thinner than oil, and the dark color comes from the pipe itself.

roughly meaning, its not some thing to freak out about.

the motor will collect condensation through out the coolling proccess (be it minutes or hours) and naturally spit them out every time you start and run the car.

I have a black spot on my garage door ( about 2 feet in diameter)

that is from my 1970, 120,000 hard miles, 240Z.

RELAX, but have it check out just for your own peace of mind.

If i'm correct, me and Beandip both live in the N.W. of the united states and we're used to it.

Dave.

[blitzkraig]

Yeah I figured it was just condensation in the system. I'll check to see if it still does that after the car has been run around the block a few times and at operating temp. Word to the wise then, don't get a Supertrapp muffler! All that black sooty water is making it look my car took a crap out the exhaust pipe! Oh well, I guess I'll just cut the thing off and put a regular flow through muffler on....

[TomoHawk]

I get that too. my tailpipe has a nice thick coat in it. I think it's a fuel/soot mix from the engine running waaay rich. I've been trying to lean it out, but still get a drop or two sometimes. I haven't noticed the oil level changing.

[beandip]

Blitz just to be sure on this , keep an eye on the coolent level to see if it drops or not . On the out side chance you have a leaking head gasket. By the way you mentioned that you just got her back on the road. If you pulled t he head , its a good idea to retorque the head after you have driven ,say 500 miles .:classic:

[TKR514]

Yea, the burning of gasoline produces water vapor. The water vapor drops out of the exhaust gasses IF the tailpipe is cold. It will drip a lot till the tailpipe and muffler get warmed up....

The black stuff is probably soot from the tailpipe mixing with the water.

No worries, it's normal.