Fireworks from the Exhaust

[L82Vette]

I just bought a 77 two months ago. 35K on the motor. If I punch it after the engine warms up the right side blows a lot of smoke. If I turn the motor off it still smokes for about 15 minutes. The right tail pipe is hot but the left is cool. My son said he saw reddish/orange sparks coming from the right exhaust. It looks like marble size pieces of carbon. Does anybody have any ideas what this might be? Could this be extreme carbon build up?
Thanks in advance
Lou :confused

 

[Stallion]

Do you hear anything when this happens? Does it sound like it's backfiring? That sounds weird that the smoke still comes out of the exaust even after the car is turned off. Maybe you have some sort of constriction in your exaust?

Possibly your cats are shot and you need new ones?

Good luck!

TR

 

[Bob Chadwick]

What color smoke? My recollection is white is coolant, black is gas and blue/gray is oil. You might be able to limit your options as to potential type of problems with this type of info.

 

[Stallion]

What color smoke? My recollection is white is coolant, black is gas and blue/gray is oil. You might be able to limit your options as to potential type of problems with this type of info.

Isn't exaust naturally white, especially on cold days? How would you know that it is coolant you are burning, and not just normal exaust?

 

[Bob Chadwick]

Exhaust on a car in good mechanical condition should not be noticeable. The reason it is white on a cold day is due to temperature. You are creating steam when the hot exhaust meets the water in the air or the small amount of water in the exhaust pipe creating by condensation. The same reason you can see your breath on a cold day.

 

[cruisin-davey-g]

Isn't exaust naturally white, especially on cold days? How would you know that it is coolant you are burning, and not just normal exaust?

Stallion: If your blowing coolant out of your exhaust, you'll know it just standing at the rear of the car & smelling anti-freeze. Also, the exhaust tip(S) will have a watery oily feeling substance on them when touched. The sort of white smoke your refering to on cold days is normal exhaust condensation & is usually light (weight) & dissapates quickly. Whereas, coolant smoke will be much heavier (thicker) & tends to dissapate at a slower rate. I would guess that your problem may be a bad converter, or a converter starting to become blocked. I'd have a muffler shop check out the exhaust system first for restrictions. Good luck!

Dave

 

[L82Vette]

The smoke is blackand it doesn't smell like oil. It smells like something is burning. The car is fine until I really get into it.

 

[cruisin-davey-g]

Stallion: If your blowing coolant out of your exhaust, you'll know it just standing at the rear of the car & smelling anti-freeze. Also, the exhaust tip(S) will have a watery oily feeling substance on them when touched. The sort of white smoke your refering to on cold days is normal exhaust condensation & is usually light (weight) & dissapates quickly. Whereas, coolant smoke will be much heavier (thicker) & tends to dissapate at a slower rate. I would guess that your problem may be a bad converter, or a converter starting to become blocked. I'd have a muffler shop check out the exhaust system first for restrictions. Good luck!

Dave

Sorry Stallion, I think my post was directed at LOU. My appoligies!

Dave (I'm losing my mind) :eek

 

[cruisin-davey-g]

Hi Lou: Boy, hope I got it right this time. Yes, your problem sounds like exhaust system problem. Get it checked out ASAP, as this could be causing damage to you motor (especially valves)

Good Luck! Dave

 

[L82Vette]

Hey Guys thanks for the info. I'll check into the exhaust system

 

[1969 Stingray]

I've only seen this once before on a truck... it happened at night when I was working at a welding shop. It was his cat that went out. The stuff coming out the pipe was the honeycomb stuff fromthe inside of the cat.

 

[Stallion]

Okay, I guess I would realize if it was coolant that she would be burning.

Yes, I thought it might also be the cats. Maybe you might want to change them. But I would find out for sure first. Good luck!!

 

[78SilvAnniv]

The right tail pipe is hot but the left is cool.

Something is certainly blocked! What have you found out?...or when will you take it in to find out?
It will be interesting to know the cause.
Heidi

 

[L82Vette]

I problaby won't be able to get it checked out until next week. I'll let you know. This week I'm in Wichita on business. What's confusing is the fact that the right exhaust is so much hotter then the left. Thanks to everyone for their input.

Lou

 

[Vette/Berlina-coupe]

-exercise CAUTION...

-Yes, certainly seems a Catylic-converter problem, in that an engine never continues to burn as you describe once it has completely stopped. Normally, once one has ignited a good CC-unit after a brief period of running, -it is indeed capable of running-on even when the engine is shut-cown, --thereby burning any final reminants of exhausted unburned fuel. Generally a single CC-unit is common to both left and right exhaust-pipes (arranged in an X-pattern basically), -however some installations employ two CC-units, and thus one could be defective; --or quite possibly one of your carburetor/idle-mixture screws may be turned excessively rich (which could cause the condition you describe, only if you have two separate exhause-pipe systems from the engine). Since the floor of the car is ignitable fiberglass-resin material like the rest of the body (will thus rapidly-oxidize in flame, -but advantageously not slowly-olidize as rust), it is critical that proper insulation be employed (such as a metal-shield above the CC-unit) as to prevent excess heating of the underbody. Suggest immediately after running the car for awhile, that with motor-off you place a floor-jack under the differential and elevate the rear high as possible, and with safety-stands secured in place beneath the frame, --take a good look-see and carefully (as not to get burned) feel around and check to discover where the hot-spots are especially. Or just take to a compentant Muffler-shop, and check with motor-running up on their lift-hoist rig...
~Bob vH
ad :nono :eek :dance

 

[cruisin-davey-g]

Hi: I believe the Vette in question is a '77 & has metal floor boards & metal firewall, as well. But, the problem should be taken care of ASAP, as tere could be potiential danger, especially to the engine itself.

Dave: