Valve seals

So yesterday, after sitting for about 2 weeks, I got the telltale blue cloud when I started my truck ('03 4.7, 165k miles). So yeah, it needs valve seals. I am very familiar with Toyota valve seals and how to do them, but trying to decide the easiest way to tackle these. I'm actually thinking pull the entire engine and pop it on a stand, leaving the heads attached. The other option is yanking the heads off the block without a total engine R&R. I mean, I suppose I could do them in the body, but it seems a bit of a pain, especially on the left with the brake booster in the way. Anyone have any experience here to offer insight?

 

Why are you thinking it's the valve seals?

Failing power steering pump air control valve can put ATF in the intake plenum and cause this exact condition. Unless you're beating the living shit out of your truck, I can't imagine why the valve seals would be going out so soon. The 4.7 is easily a 400k-500k+ engine without needing a rebuild.

More info and video of where it is here. https://www.tundras.com/threads/finally-some-good-news.95760/

Hold, on and I'll reply again with the test procedure, it only takes a minute to test.

 

Here's the 2-3 minute test procedure for power steering control valve, you're just checking for slight idle RPM increase/decrease while pinching that valve's hoses: https://www.tundras.com/threads/05-...ie-looking-for-help.61422/page-7#post-2833199

Here are some pics and location of the PS air control valve so you know what to look for: https://www.tundras.com/threads/what-is-this.107415/

Leaking injectors will also cause darker smoke at startup, here's the test for that, not quite as simple, but leaking injectors has happened here several times while valve seals, not so much: https://www.tundras.com/threads/4-7-no-start-exhaust-smoke-engine-question.74356/#post-1901687

Some other threads here covering smoke at startup, or general unexpected smoke, with some unlikely causes - I love the one that came up after a brake job - https://www.tundras.com/threads/smo...e-without-removing-heads.106363/#post-2738876

Anyway, hope it ends up being something less expensive/time consuming. Let us know what it ends up being, if nothing else.

 

Sorry to be so slow to reply. Given the fact that the valve seals have been in the truck since it was built, rubber soaking in oil, I would think that they would benefit from a swap. The smoke was definitely oil blue, so I'm not worried at all about excess fuel or water. I suppose it could be the PS valve, but my reservoir volume has not budged at all in the 3 years I've owned the truck. Just based on my knowledge of engines, a quick one-time puff of blue smoke on a cold start after sitting for some amount of time generally points to valve seals. So, I'm not at all arguing with you over other potential points of failure, just offering my perspective on why valve seals and not some other option. I'll check the PS valve when I have some time just to make sure, but I can't get past the thought that new valve seals would be a good idea. Back to my original question, should everything check out and I do end up needing to do the valve seals, would you think it easier to pull the heads, or the entire long block?