Exhaust: So what is the problem.....?

[Lou Van Anne]

This is what I find below the exhaust pipes every time I start the R2 GT Hawk....it seems to spit out water/carbon....the carburetor has been rebuilt, a leak down test and a compression test showed no issues....

[Studebakercenteroforegon]

Water is a normal by-product of gasoline engine combustion.

[studegary]

If you are referring to cold starts after not being run for awhile, that is condensation and some built up/residual exhaust material. Do not worry about it. The car may be running a little too rich or you may make a lot of short trips where the choke is at least partially on.

[Mike Van Veghten]

What Gary said.

A little rich, unburnt residue remaining, and "normal" moisture from hot/cold cycles.
You have seen rusted mufflers and exhaust systems...

Mike

[altair]

Two of the main by-products of combustion are hydrogen and oxygen that turns in to H2O, the higher the humidity the more you get. The dew point temperature in being reached inside the tail pipe, that is the temperature at which water vapour will condense. As the temperature of the exhaust gases increase the dew point temperature will also increase and will not condense until the gases are well out of the tail pipe. That is all a normal function.

[TWChamp]

That's exactly why I never start an engine unless it's going to be run for 30 minutes or more. That condensation will be resting in the cylinders and exhaust system causing rust until it's heated and evaporated. I learned this the hard way back in 1976 when I ran my 1963 Lark and 1929 Chevy for only about 5 to 10 minutes, then shut them off for 6 months. Both engines were locked tight. Also the first 1950 Champion 2 door I bought had a locked engine. After trying oil and bumping the starter several times with 12 volts I finally pulled the head. The engine looked like new inside except for one cylinder with the open exhaust valve, and that cylinder had only the slightest hint of rust.

[christophe]

It is always good practice to drill a little hole at the lowest point of the mufflers. Thus, the condensation exits directly and does not pool into the exhaust. You'll be amazed at the quantity of water you'll get there on cold startups!
Also, you'll garantee a long life to your mufflers by doing this.
Nice day to all.

[Ross]

I once had a Packard owner threaten to sue me because his exhaust threw some water/carbon on the garage wall after I had tuned up his car...

Somehow later when he needed service I could never find time in my schedule.....

[5brown1]

The carbon may be telling you your carburetor float needs adjustment. Setting the float correctly in my WW carb stopped the black stuff

[Bud]

What you see is normal for a cold start as the choke is closed and causes a rich fuel mixture until the engine warms up enough to open the choke. The wall in my garage behind my 1962 GT Hawk has soot marks on it from cold starts. Bud

[sals54]

Also... how often do you drive the car in the manner in which it was intended? High performance cars do not like to be driven like grandma cars. All the appurtenances on the car, i.e. carb, supercharger, valves, distributor, etc are intended for performance. If you're not driving the car spiritedly on occasion, you will suffer these kinds of problems.
Next time you take your car out, get it out on the freeway and DRIVE it like you mean it. Get on the onramp of the freeway and give it at least 3/4 throttle, or floor it, but run it through its paces and get it warmed up sufficiently to burn off some of the grandma sludge in the cylinders and exhaust.
I had a friend who worked at the Porsche dealer back in the 70s. Sometimes the 911s would come into the shop with complaints of running poorly. The techs would take the cars out on the "road test" and really stretch its legs for about an hour. Then give it back to the customer running like a top.
Now, I don't mean to run it over 100 mph, but let it go through the gears pulling hard to get the cylinder pressures up and hot. You'd be surprised what it will do for driveability.

[RadioRoy]

I once had a Packard owner threaten to sue me because his exhaust threw some water/carbon on the garage wall after I had tuned up his car...

Somehow later when he needed service I could never find time in my schedule.....

Some of the worst customers are the ones who do not understand the technology and are unaware of their lack of understanding. Throw a little of their self-righteousness on top of that and you have the makings of a truly bad experience.

[thunderations]

One of the funniest stories I ever heard from an old mechanic was when he told the customer that the brake pads on his car were worn more on the left side then on the right side. The customer agreed that it made sense because he braked with his left foot.

Some of the worst customers are the ones who do not understand the technology and are unaware of their lack of understanding. Throw a little of their self-righteousness on top of that and you have the makings of a truly bad experience.

[Dan Timberlake]

If the heat riser valve is working I'd expect only one pipe to spit water and residual soot for a little while, so maybe one pipe NEVER would.