Engine issues: Possible valve seals - recommendations for repair

[Hig116]

From what you said in this post, I would lean towards valve seals, bad valve seals can make it smoke on startup but also in stop and go traffic, the engine is running slow enough for oil to get passed a bad valve seal/s.

I would be very surprised if the rings have gone bad, they are metal and aren't affected from sitting unless it sat a very long time and then a ring or two could possibly get stuck but if that's your problem it would be smoking constantly, valve seals are rubber and can very easily get hard from sitting and not seal well after running again.

This was my assumption when I purchased it, or at least what I was hoping as worse case scenario. This if my son's car. He had another 2015 SR5, but rear ended someone and totaled it. The new one runs just as good as his old one, so I don't feel like there are any performance issues, which I would suspect would be present if it was an issue with the rings.

So I may be jumping to far ahead, but are there any resources out there that show the method for replacing the seals? I found one that was for a similar engine that showed how to do it without removing the timing chain. I'm hoping for a simpler approach, as I know it is going to be time consuming and my first time tearing into anything other than a SBC350.

 

[AuSeeker]

This was my assumption when I purchased it, or at least what I was hoping as worse case scenario. This if my son's car. He had another 2015 SR5, but rear ended someone and totaled it. The new one runs just as good as his old one, so I don't feel like there are any performance issues, which I would suspect would be present if it was an issue with the rings.

So I may be jumping to far ahead, but are there any resources out there that show the method for replacing the seals? I found one that was for a similar engine that showed how to do it without removing the timing chain. I'm hoping for a simpler approach, as I know it is going to be time consuming and my first time tearing into anything other than a SBC350.

I'm not sure of the procedure for this engine, but on all engines I have worked on you have to remove the valve spring to replace the seal and these having overhead cams you would have to remove the cam to get the spring off, if it were an old school engine with rocker arms it easy to do.

 

[Hig116]

I'm not sure of the procedure for this engine, but on all engines I have worked on you have to remove the valve spring to replace the seal and these having overhead cams you would have to remove the cam to get the spring off, if it were an old school engine with rocker arms it easy to do.

Yes, I saw that you have to remove the cams and I found a cool tool for removing and installing the springs. I'm really just hoping I can find something that helps give me guidance on disassembly so I don't spend time removing things I don't need to or in the wrong order that takes even more time. These engines have so much more sitting on them than an old carbonated motor. :scared:

 

[AuSeeker]

Yes, I saw that you have to remove the cams and I found a cool tool for removing and installing the springs. I'm really just hoping I can find something that helps give me guidance on disassembly so I don't spend time removing things I don't need to or in the wrong order that takes even more time. These engines have so much more sitting on them than an old carbonated motor. :scared:

I just spend 30 minutes on Youtube trying to find a video to help you..but all
I found was a couple that only showed them removing the seal and installing the new one and they had the heads completely removed, so no real help I'm afraid.

Edit: I just had a thought, if you search for a how to guide for "valve adjusting" since you have to remove the cams to add and or replace a shim under the "buckets" to "adjust" them, that would get you to the valves so you can then replace the seals!!

Before you pull the cams you going to need to note all the valve clearances in case any need to be "adjusted" and then make sure to keep the buckets and shims organized/labeled so they go back in the exact same place they were removed from during reassembly.

 

[03_4x4Runner]

Go to around 4:20 on this and see if this hose is connected.

https://www.youtube.com/watch?v=V02O8YGuc4U&t=4s&ab_channel=TheCarCareNut

 

[Soso-clean]

Keep us posted. I'm having the same issue 80k

 

[Hig116]

I just spend 30 minutes on Youtube trying to find a video to help you..but all
I found was a couple that only showed them removing the seal and installing the new one and they had the heads completely removed, so no real help I'm afraid.

Edit: I just had a thought, if you search for a how to guide for "valve adjusting" since you have to remove the cams to add and or replace a shim under the "buckets" to "adjust" them, that would get you to the valves so you can then replace the seals!!

Before you pull the cams you going to need to note all the valve clearances in case any need to be "adjusted" and then make sure to keep the buckets and shims organized/labeled so they go back in the exact same place they were removed from during reassembly.

Over the past week, I have spent hours trying to find videos or websites around this issue or similar. I guess it's a good sign that no one is needing to tear into these engines.

Your valve adjustment search is a fantastic idea. I'll look into that and see what I can find.

Thanks

 

[Hig116]

Keep us posted. I'm having the same issue 80k

Absolutely.

 

[rdruss]

I'd keep driving it for awhile, do an oil change with Valvoline "Restore and Protect" oil and stay with it for a couple of changes unless problem gets progressively worse and you feel a repair is necessary. Check your plugs for any signs of oil contamination.

 

[Rocko9999]

FWIW when I bought my high mileage 2011, it had this to a much lesser degree. I suspect it sat for a while also. I went through the head gasket checks, etc. I changed plugs, pcv valve, oil, added Techron, scoped the cylinders and it had decent amount of carbon build up I am sure some from oil-all the things I listed and after 1-2K miles it stopped. Not saying yours will. But mine had many more miles on it-242K-when I bought it.

 

[Hig116]

Have you tested for blow by - basically open the oil fill plug, put a rubber glove over it, see if it inflates while running. If not - that tends to point away from rings and toward valves. Excessive blow by could result in more oil burning via the EGR system.

I would personally start with a heavy dose of fuel system cleaner and see if it's an issue with valve carbon buildup. That's unlikely with a port injection engine, but if it's valves that's possibly the only thing you can really do before pulling it apart.

If it has piston ring issues - you could look inside with a scope to see if the cylinder walls are scored. If you see issues - you kinda know at that point you're looking at an engine. I would tend to swap a low mile used one vs a rebuild.

Good luck.

Edit: just watched the video,

Hard to tell from the video what the smoke smells like or how it looks in person. It also kinda looks like it could be over-fuel on startup. If it's unburned fuel it could be an over-fuel on startup from a variety of issues like injectors, spark plugs, dirty air filter, air flow sensor, etc. Have you checked the air filter? Pulled spark plugs? (Do any of them look different from the rest?)

I just tried the glove trick and the opposite occurred. There is vacuum pulling the glove in. Is that right? What does that mean?

Edit: I don't see how there would be vacuum here, but it could explain oil being pulled into the cylinder and causing my smoking issue. The question is why? The vacuum would have to be coming from an intake valve, right? Does that mean I have a bad valve or one stuck open? Seeing how well it runs, I wouldn't think so?

 

[Hig116]

I just found a thread about the same problem on a 1ZZ-FE motor someone installed. This was what the found to be the problem:

"Absolute rookie mistake. We had two hoses hooked up wrong. The pcv hose and the hose on the front of the valve cover were hooked up to the wrong ports. One goes on the intake manifold, one on the throttle body, and they were backwards."

I would love if it were these easy, but I'm not sure these hose are close on my engine and if it is even possible to swap them. But, it does make sense. I can't tear into it for a few days, but wanted to post this to see if it sparked any ideas.

Keith

 

[AuSeeker]

I just tried the glove trick and the opposite occurred. There is vacuum pulling the glove in. Is that right? What does that mean?

Edit: I don't see how there would be vacuum here, but it could explain oil being pulled into the cylinder and causing my smoking issue. The question is why? The vacuum would have to be coming from an intake valve, right? Does that mean I have a bad valve or one stuck open? Seeing how well it runs, I wouldn't think so?

If you had a bad intake valve there would be vacuum on the intake stroke but have pressure on the compression stroke, so I don't see how a bad intake valve would cause a constant vacuum in the valve cover, it would be affecting the intake not the valve cover, backfiring out the throttle body, etc., so I don't see how a bad intake valve could make a difference in pressure in the valve cover.

A compression test and a leak down test would rule out a bad valve.

 

[Hig116]

If you had a bad intake valve there would be vacuum on the intake stroke but have pressure on the compression stroke, so I don't see how a bad intake valve would cause a constant vacuum in the valve cover, it would be affecting the intake not the valve cover, backfiring out the throttle body, etc., so I don't see how a bad intake valve could make a difference in pressure in the valve cover.

A compression test and a leak down test would rule out a bad valve.

Me either. As I'm learning more about the engine from extensive Google searches, I see the PCV valve is on the same valve cover. If there is vacuum in this valve cover, I don't see the PCV being able to vent to the intake. So, this vacuum can't be right.

 

[AuSeeker]

Me either. As I'm learning more about the engine from extensive Google searches, I see the PCV valve is on the same valve cover. If there is vacuum in this valve cover, I don't see the PCV being able to vent to the intake. So, this vacuum can't be right.

There should be some vacuum in the valve cover so the crankcase ventilation A.K.A. PCV (Positive Crankcase Ventilation) works, it's the system that sucks the combustion blowby gases that gets by the pistons out of the crankcase VIA the heads and into the intake to be burned.

That's only as long as the PCV and any other vacuum lines going to the valve covers are still connected.

 

[Hig116]

There should be some vacuum in the valve cover so the crankcase ventilation A.K.A. PCV (Positive Crankcase Ventilation) works, it's the system that sucks the combustion blowby gases that gets by the pistons out of the crankcase VIA the heads and into the intake to be burned.

OK. Seemed like a lot, but I truly don't know how much (if any) should be there, so it was an assumption.

I believe I'm going to try an oil change with Mobil 1 and see how it does. My son is taking it back to college next weekend, so I'm just trying to feel comfortable with it being reliable with him being 2 hours away.

Keith

 

[AuSeeker]

OK. Seemed like a lot, but I truly don't know how much (if any) should be there, so it was an assumption.

I believe I'm going to try an oil change with Mobil 1 and see how it does. My son is taking it back to college next weekend, so I'm just trying to feel comfortable with it being reliable with him being 2 hours away.

Keith

I added another sentence to my above post while you were replying.

 

[Hig116]

I added another sentence to my above post while you were replying.

Gotcha. I think I'll pull the cover off to get a better look around and see if anything obvious jumps out at me.

Thank for all of your replies.
Keith

 

[Hig116]

If the car was flooded, could it cause this issues? I’m finding signs it was under water to some extent, but not sure how much. Found sediment on top of the front a arm and dirt in the headlights

 

[Hig116]

My son returned from having the car at college for a couple weeks and the smoking issue is the same. In fact, he parked on a steep driveway yesterday and it really smoked bad when he cranked it. This helps me think it's the seals.

Today, he got the P0024 error code, which is the VVT oil solenoid on bank 2, I hope. I really am starting to wonder if the car was flooded and maybe there is some sludge in places, like the oil solenoid. I've decided to replace the valve seals after the first of the year.

Keith