jbrekle

Hey guys, first post here. I've got a '73 Chevy K10 pickup with a 350 motor and a 350 turbo behind it. I got it about 8 months ago and ever since I've had it, a smoke out the exhaust issue has gradually gotten worse. I'm fairly certain that it did not happen when I first got it, and now it starts smoking pretty much as soon as it warms up. I want to say it is oil, and from what I've read, the valve stem seals if so. It seems to have a bit of a bluish tint to it but sometimes I second guess myself about the color (I know blueish is oil, white is water/.antifreeze). And it never smokes on startup, but once the engine is warm, it will start to smoke a bit at idle and then as soon as I hit the gas, boom, a bellowing cloud of smoke. And it happens out both sides of my completely independent dual exhaust. What kind of has me confused is that a) it doesn't do it at startup, which makes me think it may be water once more is circulating after it warms up. b) it seemed to start out both sides of the exhaust at the same time/rate. What are the odds that the valve stem seals on both sides of the motor started going equally bad at the same time?

I noticed that the valve cover gaskets were leaking decently onto the header gaskets, so I replaced both the valve cover gaskets and the header gaskets because they were relatively easy to do and needed to be done anyways. I hoped that would fix it, but did not. This also gave me an opportunity to see what the valve stem seals maybe looked like. With the covers off, I saw that the valve springs had the shroud style (the metal umbrella that mounts to the top of the spring) on all the springs as well as rubber umbrella seals on the intake valves. The rubber seals looked to be the new FelPro premium valve stem seals that have a metal band on them to help keep them in place and looked to be in fairly good condition. There were no remnants of rubber flaking away, and like I said, looked to be the FelPro premium ones that I would assume were done somewhat recently. I did not see a rubber or hard plastic seal on the exhaust valves, just the metal shroud, but the exhaust valves are under positive pressure too, unlike the intake valves, so I would think that they are OK then.

Anyways, this is kind of where I'm at, not sure if I should spend the time/money to replace the valve stem seals I have the new FelPro rubber ones for the intakes and the harder plastic ones for the exhausts along with the o-rings for each. I have never done valve stem seals before and would only like to do them if I need to/know it is actually the problem. So I guess what I'm trying to ask is, if anyone thinks they know what the issue may be before spending time/money doing something useless? Would it be worth trying like a oil seal conditioner or a antifreeze leak additive as they are usually cheap and easy to try? And even if it only helps a little or temporarily, that may help indicate what the actual issue is.

Let me know if pictures or a video of the smoke or anything would help at all with determining what is happening.

Thanks,
James