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-   -   Lotsa smoke at startup. (Stock Chevy 350 with Q-Jet carb) (

Terje 07-16-2004 06:51 PM

Lotsa smoke at startup. (Stock Chevy 350 with Q-Jet carb)
Ok, it's me again. Just passed smog, and now I'm willing to invest a little more time and money on this thing. Not quite sure how much though.

Every time I start this thing, it puts out alot of smoke.

When it's cold I can floor it once before starting it, then start it very easily just by turning the key. This is to be expected because it being cold and not running when I floor it activates the fast idle cam.

When it's hot, and I go to start it, I have to turn the key and quickly give it a little gas to get it to start.

Is this normal behavior for a 1977 Chevy PU with a 350 and a Rochester Q-Jet?

I was told by the guy I bought the thing from that it has bad valve seals, and that's why it's blowing smoke whenever I start it up.

Is this correct? Is the only way to fix it to have the heads rebuilt? If I were to have the heads rebuilt is there anything I can also have done without increasing the cost at all or by increasing the cost a little that might improve HP performance or gas milage performance significantly?

What other things might cause alot of smoke on startup?

87442lover 07-16-2004 07:00 PM

valve seals, oil slipping past rings on startup, nothing show stopping. There are tools so you can replace the seals while the heads are still on the engine. Seals are also real cheap to buy.

M&M CUSTOM 07-16-2004 07:11 PM

Valve seals and rings, the 23 year old 267 in my Malibu has the exact same thing, blue smoke at start-up.

For comparison purposes.

If you have black smoke it is from too much fuel.

White steamy exhaust at start-up is normal, BUT after the engine is warmed to operating temperature you would be experiencing a coolant leak into a cylinder from most likely a head gasket failure.

Terje 07-16-2004 08:08 PM

I will have to look into getting those tools. Are they expensive? Hard to use? Will they work on any vehicle, just V8's or just some V8's?

I'll try searching google and see what pops up.

Terje 07-17-2004 02:54 AM

I found this:

I just happen to already have exactly this tool, but didn't know what it was for.
(My uncle moved out of the country and gave me all his tools instead of selling them)

Air Hold Fittings.

What else do I need?

roys63 07-17-2004 05:46 AM

If this has a auto trans it may be the Modulator valve in the trans pulling trans fluid into the intake, check the hose and see if it is wet in side, This will smoke real BLUE and have a kind of sweet smell ?

troy-curt 07-17-2004 06:16 AM

If it was a modulator, it would smoke all the time.

Sounds like valve guide seals to me. And you have the right tools.


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Terje 07-17-2004 03:09 PM

Yes, it is an automatic.

So far:
1. Modulator valve in the trans pulling trans fluid into the intake.
- Smokes real blue all the time.

2. Oil slipping past rings on startup.
- Wouldn't this happen all the time? Not just at startup?

3. Valve seals leaking oil.
- Bluish smoke at startup.

4. Too much fuel.
- I guess this could occur all the time or just at startup. Is there an explanation for why this would only occur at startup? I can't tell if the smoke is blue, black or brown. There's not enough. It doesn't appear to smell sweet. But it does smell a bit like gas.

I'll have to keep looking at it a bit every time I startup and try deciding what it smells like.

I'm guessing that it probably is the valve seals, and it appears to be cheap enough and easy enough to fix. So even if that's not the problem, as long as I don't mess up the valve seals putting in new ones, it won't matter too much if the valve seals were not the problem.

roys63 07-17-2004 06:57 PM

I guess we need a Cristal Ball.

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