Author Topic: Smoke on startup  (Read 4241 times)

Offline RC 415

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Smoke on startup
« on: January 14, 2007, 03:46:00 pm »
Every morning when I start my 1983 chevy the truck produces a lot of grayish/blackish smoke out the tailpipes for about 3 minutes, the truck has a newer 350 crate motor with about 5k miles on it, and it also has new plugs, plug wires, and dist cap, a recent radiator and flowmaster dual exaust. What could be causing this?


Offline 75 C20

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Re: Smoke on startup
« Reply #1 on: January 14, 2007, 06:00:00 pm »
sounds like valve seals to me

1975 Custom Deluxe 20 350 SM465 2WD Longbed
1979 Custom Deluxe 20 400 SM465 2WD Longbed
1968 Custom Sport Truck 20 327 TH400 2WD Longbed
1985 Silverado 10 305 700R4 2WD Longbed
1969 Pontiac GTO 400 Turbo350
2008 GMC 2500HD 6.0 6spd 4X4 Longbed

Offline RC 415

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Re: Smoke on startup
« Reply #2 on: January 14, 2007, 07:55:00 pm »
so you think it oil?


Offline RC 415

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Re: Smoke on startup
« Reply #3 on: January 14, 2007, 10:51:00 pm »
Well I was just told that the choke needs adjustment, as the truck is running too rich in this cold weather, anyone know how I go about doing this?


Offline 75 C20

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Re: Smoke on startup
« Reply #4 on: January 15, 2007, 03:19:00 pm »
wut kinda carb u got?

1975 Custom Deluxe 20 350 SM465 2WD Longbed
1979 Custom Deluxe 20 400 SM465 2WD Longbed
1968 Custom Sport Truck 20 327 TH400 2WD Longbed
1985 Silverado 10 305 700R4 2WD Longbed
1969 Pontiac GTO 400 Turbo350
2008 GMC 2500HD 6.0 6spd 4X4 Longbed

Offline RC 415

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  • Posts: 7
Re: Smoke on startup
« Reply #5 on: January 15, 2007, 09:07:00 pm »
Rochester 4Bbl, The choke is electric


Offline VileZambonie

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Re: Smoke on startup
« Reply #6 on: January 15, 2007, 10:39:00 pm »
Black smoke = unburned fuel

blue/grey smoke = oil

white smoke = ATF or Coolant

So 1st determine what color smoke you have. Just take the air cleaner off and see if the choke flap is opne when it's warm

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