engine question???

[chaz]

Hey guys I need some help on a problem I think. I have a 21' Commander with a stock 454 and a 12-JE pump. After going for a ride and then letting it sit for a while, when I start it up I get some black stuff comming out of my exhaust. I don't know if something is loose or a seal is broken, need some help.
Thanks http://free.***boat.net/ubb/confused.gif

[rstover1]

Black smoke typicly means your boat is flooding out or running to rich check you plugs the floats in your carb are probably sticking.

[chaz]

it is not black smoke comming out, it is like powder and it floats on the water

[rivercrazy]

Still sounds like very rich condition.

[058]

Are you running a Holley? If you are it probablly is a blown power valve. It also could be a leaking needle/seat or a jet well plug leaking [Q-jet]. Raw fuel is leaking into the engine while its shut off. This needs to be corrected ASAP, engine damage can result such as gas washing cylinders, oil dilution and worst case, hydralic a rod. [trying to compress a liquid]

[Havasu Hangin']

Are you pumping the throttle to start it? Does it smell like raw fuel?
Rich condition ususally looks like black smoke, and oil burning has a blue-ish tint. They smell different, but both can produce a sheen on the water. Powder, hmmm- might be carbon? Are your wife's cosmetics accounted for? http://www.goldenplasma.f2s.com/forum/smilies/confused46.gif

[chaz]

I am running a Holly but I don't know what kind, what is the best way to go, new carb, get it rebuilt and what is the cost on getting rebuilt. And yes I thinks it is carbon on what is comming out of the exhaust.

[Boater Bill]

Also check your flappers and exhaust hoses (exhaust manifold to exhaust tips) if so equipped. If you are not running enough water through the exhaust you will burn these up pretty quickly. When the exhaust hose(s) start to deteriorate they throw out black residue.

[oldphart]

If your guide seals have gone hard you will burn a little oil, thus carbon on start up. it's no big deal unless it gets excessive. on our race motors we dont even run seals on the exhaust side and you get a little black floating scum on start up.

[77Spectra]

Since the boat was running fine before parked, try this. At the beginning of the season you should remove the bowls. I bet water may have gumed up the works. Get a new power valve and install, they are cheap. Most boats I work on at the beginning of the season, this is ussally the cure all...