white/blue smoke at beginning of a trip

[Bradsp8]

Any ideas as to why I have some white/bluish smoke at the beginning of a trip? Background: it's a 75 (smog gear included) with stock 302 with 76k miles and slowly burns a quart (maybe a bit more) of oil (10-40) over the course of 1,000 miles. It usually sits for days between drives and when I do drive it I usually let it sit and idle a few minutes before heading out. As I drive slowly out of the neighborhood I come to a stop light. When taking off from the light I can see cloud of smoke behind me that is white/blueish in color. Not thick smoke but certainly noticeable. After this initial smoke cloud it doesn't do it the rest of the day, only when I first get into the gas. I have headers and dual exhaust and the smoke does shoot out from both tail pipes equally. Do I have major problems needing to be addressed or is it due to normal age and wear?

 

[Steve]

Sounds like worn valve guides, which is normal wear and tear and not terribly expensive or difficult to fix if you're so inclined.

 

[vintage bronco]

well if it sets for days at a time i would say its the valve seals. with age of them they become hard and brittle,they also can be changed out with the heads in place.

 

[markperry]

Yes you could go with the SHADETREE method of valve guide replacement, by shoving an old sparkplug wire in the cylinder, then turn the engine over until the valve doesn't move ,then replace the guide.

But I would take the opportunity to take the heads off and do a valve job and whatever else it needs! Just my two cents!

 

[Stroppe-Envy-77]

Sounds like worn valve guides, which is normal wear and tear and not terribly expensive or difficult to fix if you're so inclined.

The way he describes it, does it sound like slightly worn cylinders where some oil gets past the rings before everything warms up fully?

I've had cars with worn valve guide seals before, and that usually means one puff of smoke at startup. Whatever dribbles down past them overnight or over a few days is burned off almost instantly. If he's driving a few blocks with oil smoke coming out of the exhuast, that doesn't sound like the seals.

A compression and leakdown test will help find the answer.

 

[Steve]

The way he describes it, does it sound like slightly worn cylinders where some oil gets past the rings before everything warms up fully?

In my experience bad rings smoke all the time, not just at startup. Worn valve guides smoke at startup for a little while.

 

[Viperwolf1]

A vac leak at the intake gasket will cause it to suck oil much like that of worn valve seals.