Timing Chain Cover (1 Viewer)

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i have a buddy with at 2011 LC that he just inherited from his in laws. It has a leak from the timing chain cover. I told him this would be an expensive fix. He did some research and found that the leak is in a low pressure area and will never amount to much. He is opting on leaving it as is. It’s not leaving a puddle, just has collected dust on the light oil coating. None of the leak area is wet, just dusty. Was I correct in telling him it needs to be done? I also told him about cam tower lease, but I don’t see anything under the valves covers, or near the exhaust headers. Do they normally do the timing cover and cam towers together?
 
you dont have to do the cam carriers when you do the timing cover, but you do have to do the timing cover when you do the carriers. if its not leaking badly why reseal now, reseal when it gets worse or the cam carriers start to leak
 
Is he right about it being in a low oil pressure section of the motor? Is this a precursor to the cam towers leaking? This free car is going to set him back a few grand in maintenance.
 
If I'm reading it right, it basically is the cam tower leak. This leak isn't high pressure or very intrusive. The "cam tower" leak is pretty much an extension of the valve cover. It's not enormously important to take care of but will cause issues if not tended to.
 
Got it. So, important to get done, but not critical until it start to leak for real? How do you tell the difference between the cam tower and the timing cover leaks?
 
Great idea. I'll let him know. At least it will pinpoint the problem area. Is it safe to say if the timing chain cover gasket needs changing the cam tower seals will be next to fail?
 
It does sound like the veritable cam tower leak. It is an expensive fix due the the necessary labor to get at it.

The labor would pay for a ton of oil. For any oil leak, there's always a choice to repair or not. People have lived with far worse leaks, by just adding more oil. In older vintage cars, leaks were common place, and accepted. Cars really don't care, so long as the crankcase has sufficient oil to lube the motor.

This particular leak is more cosmetic than a functional problem. And probably wouldn't require much topping off if any.
 
NO. The cam tower leak is the result of what in the auto industry is known as a spill. An assembly line error, which was not confined to a single vehicle, but wasn't discovered until the dealerships complained (which amounted to several hundred units) is the source of this problem.

The problem was someone with dirty hands applied the sealant and it didn't sure properly. This is confined to only a couple of months. Toyota should have placed a recall, but they didn't. A dealership might (might) fix it, but it's unlikely, unless the truck was purchased there.

This failure has nothing to do with normal (or abnormal) wear. It is definitely not related to a failure on any other component or seal. And it's not necessarily expensive either. If you have some basic tools, and time, you can do it yourself.

If there is another leak, and there is no noticeable oil consumption between regularly scheduled changes, I'd let it go. There's more than enough oil in the engine to keep it good, if there's a low pressure leak (or weep) from the top end. If the leak was at the bottom end, I'd be more concerned.
 
That's what he was thinking. He had a dodge omni in college that burned a quart of oil every 500 miles. He's philosophy was oil is cheap rebuilding a motor is expensive. I had a main seal leak from day one on my Cuda 340.
 
The problem was someone with dirty hands applied the sealant and it didn't sure properly. This is confined to only a couple of months. Toyota should have placed a recall, but they didn't. A dealership might (might) fix it, but it's unlikely, unless the truck was purchased there.

What model year(s) was affected?

TIA
 
From what I understand from the post here the LC and LX effected were 08-10. The domestically made tundras stil have problems currently.
 
From what I understand from the post here the LC and LX effected were 08-10. The domestically made tundras stil have problems currently.

Three model years - 2008, 2009 and 2010 - does not square with "a couple months" of production as stated by @Malleus . I was hoping he could clarify/confirm his post.

HTH
 
The timing chain cover is nowhere near the cam tower leak area. Pictures would help this situation a ton.
 
Getting the camp Tower leak fixed is important because the oil runs onto the exhaust manifold and I was concerned my engine was possibly going to catch fire because oil and heat and smoke eventually could equal fire.

Both cam towers, and the front cover reseal bill on my 2011 was over $4,000!
 
I'll get him to click some photos and post it for him. I didn't see any oil near the exhaust maninfolds from the sides of the wheel wells. The staining was limited to the lower right portion of the front of the motor. There is some dirt on the right lower portion of the right head but not near the valve cover.
 
I apologize for my misleading comments. The length of time observed (this is the only point of reference I have, because Toyota hasn't seen fit to claim responsibility for the error) over the model lifetime of a decade (or more, in the case of the 200) is a couple of months, from the point of view of the manufacturer. I didn't mean to trivialize the problem. It's real and a PITA as well. Unfortunately, I don't have any clear insight as to when the problem started or ended, other than the comments posted on this forum. I know it started after the '08 model year started (mine's a Dec '07) and it's apparently been resolved.

From what I've been able to glean from the comments here, the problem was that someone was simultaneously employed in assembling the valvetrain and installing the covers. Assembly oil used in the valvetrain area was apparently on the hands of the same guy who handled the cover. The oil kept the RTV from curing, leading to the eventual leak. The solution was to completely remove the gasket material, clean everything, and reassemble. Once the root cause analysis was completed, the problem disappeared. I have no explanation for why this would have occurred in two different locations. This kind of problem is usually location specific, usually due to staffing choices. (new people in unfamiliar areas, for a short period of time, to cover for personnel shortages, etc.) Once the root cause analysis is completed and a "fix" is designed and implemented, the word goes out to everyone in similar areas, to keep this kind of thing from happening again.

Another item of interest (at least to me), I haven't heard of any LX570s having this problem, only 200s. I also irregularly watch the Lexus owner's forum, since it's a good measure of the frequency and severity of fleet problems (lots of whining over there, not much solid, useful advice). I have yet to hear the problem there.

This leads me to wonder if the LX engines are built differently, or at least segregated from, the 200/Tundra engines. This would explain the lack of problem on the same engine in one of three different models, which supposedly get the same drivetrain. Something to keep in mind if you're in the market for a replacement engine.
 
I don't really buy the booboo during assembly deal. There must be a reason for two assembly plants on opposite sides of the globe having the same mistake. Could be a training deficiency or a lack in tech data for the assembly guys or poor quality of sealant. I don't think it's as simple as one dude screwed up.

As for LXs being less susceptible; I think most LXs that are owned during the period where this leak can occur (60k-90k) are mostly driven by housewives or dudes who don't really know or care about a leak. They just bring it in for maint, and have the dealer fix whatever is wrong under warranty and move on. As opposed to hopping on a forum to ask questions about it.
 
My 2013 cam tower began to leak a significant amount of oil at 68,000mi. I immediately took it to the dealer, I'm no wrench and since it was under an extended warranty I felt it was their obligation to fix this factory defect. My bill came up to around $2700.
 

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