Truck Leaves Blue Smokey Haze on Hwy......

[ashx2]

When I bought my truck and drove it home from Oklahoma, I never noticed any blue smokey haze in my rearview or side mirror. Now, several months later, when I take it onto the hwy, I see the blue haze behind me.

I'm not sure what the PO was using for oil, but I've been using Castrol 10w-30. Now I'm beginning to wonder if that's the reason for the smoking or could it be something else? Nothing else is making any noise or vibration of any kind, so I'm a little puzzled. Not to mention, it's embarrising for my classic to be leaving that kind of haze for others to see or drive through.

Anybody have any ideas or similar experiences?

Thanks,
Greg

[RSCamaro]

Originally Posted by ashx2

When I bought my truck and drove it home from Oklahoma, I never noticed any blue smokey haze in my rearview or side mirror. Now, several months later, when I take it onto the hwy, I see the blue haze behind me.

<SNIP>

Thanks,
Greg

Valve guides, rings, PCV valve. Probably the previous owner either put in some kind of additive or just used 20W-50 oil. A compression leakdown test is where you should start though valve guides is the most likely culprit. Of course it could be something simple like a small oil leak falling on the exhaust.

...Ron

[ashx2]

I'll hope for the simple part. I do know that the chrome valve covers are not sealing down real good. I've got an original set given to me by an older gentleman here in town that I plan on putting on w/some new gaskets. Maybe I'll get lucky and that'll fix the problem.

Greg

[cdowns]

if you've got cheapo chrome valve covers with no baffels and a PVC system the carb is sucking the oil into the engine causing the blue haze now dont confuse that with purple haze cause thats a whole different thing

[68gmsee]

Rule of thumb: Bluish smoke when you first crank it up or after it sits for a while, usually are the valve guides. Bluish smoke on the highway at higher speeds, usually rings.

I say rule of thumb because there could be a combination of things causing the haze, as mentioned. Since you're not familiar with the engine or what's been done before you got it, it would definitely be wise to start with a compression check and check all of the easy problem areas.

My guess is with the rings.

[SacramentoJoe]

Rule of thumb: Bluish smoke when you first crank it up or after it sits for a while, usually are the valve guides. Bluish smoke on the highway at higher speeds, usually rings.

That is the thumb that I have always used. You can really notice if it is the rings after a long decelleration like a downgrade.

[ashx2]

It doesn't smoke any at start up or when I am cruising through town (35-45 mph), but when I get on the hwy and do 55 or above......I see the blue haze behind me.

cdowns......No purple haze seen, nor have I been kissing the sky. LOL! And yes, that would be a very different thing!

Greg

[68gmsee]

From the way you describe it, I'd suspect the rings. Oil thins out after it gets hot and seeps past the rings at higher speeds.

It could be the rings are stuck with carbon buildup. If you're not thinking of a rebuild right now, maybe some oil or fuel additives my loosen them up.

[Stocker]

Gotta admit my first thought about your truck leaving a trail of blue smoke was...... Too much torque for the tires to handle!!


But you got some great advice above... check the VC gasket -- rings may be the most likely issue -- leakdown test is your best bet to find out for sure. You might be able to buy some time with 20W50 oil.

[71meangreenc10]

Also check to see if the oil drain holes in the head are clogged up. I had a 350 that had that and they were full off crap which led to the situation you described. Cleaned them out and no more problems. Must have been using Quaker State )

Smitty