My 2014 LX570 has the chain tensioner issue and concomitant rattle. The question I can't find the answer to is, does this necessitate replacement? I.e., will damage occur or is it only a noisy nuisance?
Does Chain Rattle Dictate Replacement? (1 Viewer)
- Thread starter Von Hayek
- Start date
This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.
bloc
SILVER Star
I vaguely remember IDoCars tearing down a 3UR that had skipped timing or broken a guide or something… this was an older video, not the recent one with the broken cam gear bolt. Though TBH that sort of implicates the timing chain tensioner, in my head anyway.
So while the rattle isn’t uncommon, actual damage as a result seems to be rare.. or, it’s doing damage that isn’t bad enough to kill an engine right away, but in 50k miles? Or 80?
What is clear to me is that sound indicates forces in the timing system that it was not designed for. Bad sounds, lots of force/wear.
As Teckis said lots of people have had great results running a thicker oil, myself included. I got a really bad version of the rattle a handful of times running the stock 0w-20, and none that I can remember since switching to 5w-30 something like 60k miles ago. And that’s without seafoam or any other treatments.
So while the rattle isn’t uncommon, actual damage as a result seems to be rare.. or, it’s doing damage that isn’t bad enough to kill an engine right away, but in 50k miles? Or 80?
What is clear to me is that sound indicates forces in the timing system that it was not designed for. Bad sounds, lots of force/wear.
As Teckis said lots of people have had great results running a thicker oil, myself included. I got a really bad version of the rattle a handful of times running the stock 0w-20, and none that I can remember since switching to 5w-30 something like 60k miles ago. And that’s without seafoam or any other treatments.
- Thread starter
- #4
Wow. That's impressive. Thicker oil coming. Thanks gents.
What oil are you using now?
Are these usually high mileage motors?
- Thread starter
- #7
Factory 0W-20.
So ya move to 5w-20 full syn. Another thing… I just cleaned out part of my air cleaner and throttle body with a carb cleaner in hopes of reducing start up high idle time and idle rpms. If you’re hanging out with the hood open sometime pull off the rubber hose and spray both sides of that valve. It develops a dirt ring around it and doesn’t seal properly.
bloc
SILVER Star
Meaning the throttle body?
If so, people should be very careful with this cleaning job. Don’t want chunks of that going into the intake. And personally I don’t want my engine ingesting much carb cleaner.. stuff can end up in the oil, hard on seals, etc.
I removed my throttle body to clean it properly when I replaced my under-intake foam blocks. In doing so I realized the mesh strainer behind the TB needs to be cleaned at the same time.
Also did you mean 5w-20 or 5w-30?
Ok, If you see chunks inside the throttle body please have your engine looked at by a certified mechanic, and if you choose to do this DO NOT start the engine for at least 10 minutes so the carb cleaner can dissipate.
I can't speak to the 3UR, but can say that in other engines (ahem: eCoBoOSt) if you hear the timing chain "rattle," it's a sign of inadequate lubrication/timing chain stretch the phasers have to adjust quickly to take up that chain slack causing the rattle.
The lube bit is taken care of as mentioned by @bloc and @PDoyle suggesting running thicker oil. Again, I can't say anything specific about how this may or may not affect your engine in the future but you're doing the right thing by trying to address it immediately.
Unsolicited experience with TB cleaning: I cleaned my TB without removal, but sprayed TB cleaner on a microfiber towel and gently opened the butterfly to clean along the area where the butterfly would rest at full close. I disconnected my battery first and was very slow with opening/closing the butterfly. This worked well for me around the 50-60k mark and I didn't have to remove the TB assembly with my ham hands. I would suggest this method if you're like me and can find creative ways to destroy good parts without meaning to.
The lube bit is taken care of as mentioned by @bloc and @PDoyle suggesting running thicker oil. Again, I can't say anything specific about how this may or may not affect your engine in the future but you're doing the right thing by trying to address it immediately.
Unsolicited experience with TB cleaning: I cleaned my TB without removal, but sprayed TB cleaner on a microfiber towel and gently opened the butterfly to clean along the area where the butterfly would rest at full close. I disconnected my battery first and was very slow with opening/closing the butterfly. This worked well for me around the 50-60k mark and I didn't have to remove the TB assembly with my ham hands. I would suggest this method if you're like me and can find creative ways to destroy good parts without meaning to.
- Thread starter
- #13
Only on cold starts.
I have this issue where I get a slight rattle off and on again upon cold starts. Happens a few mins after starting up and then goes away when fully warmed up. I've noticed that it doesn't do this until it's around halfway through or more on my oil change intervals (5K miles).
Bought vehicle at 155K, now has over 190K on it. In its service history from the original owner it was actually mentioned a few times and when under warranty, had the driver side cylinder head taken apart and timing assembly replaced for this issue. Apparently, it didn't solve it permanently but it gave me some piece of mind knowing it was already looked at/addressed. They probably preemptively even fixed any Valley plate issues while they were in there!
In my ownership time I've switched to 5w-30 in hopes of making it go away. It did for a bit but then comes back around when I need an oil change again. I've since switched back to 0w-20. Maybe I'll try the Seafoam thing but overall, I don't think it's an issue.
Hopefully others can chime in with additional experience.
Bought vehicle at 155K, now has over 190K on it. In its service history from the original owner it was actually mentioned a few times and when under warranty, had the driver side cylinder head taken apart and timing assembly replaced for this issue. Apparently, it didn't solve it permanently but it gave me some piece of mind knowing it was already looked at/addressed. They probably preemptively even fixed any Valley plate issues while they were in there!
In my ownership time I've switched to 5w-30 in hopes of making it go away. It did for a bit but then comes back around when I need an oil change again. I've since switched back to 0w-20. Maybe I'll try the Seafoam thing but overall, I don't think it's an issue.
Hopefully others can chime in with additional experience.
bloc
SILVER Star
My understanding is the 3UR “bad” rattle isn’t a phaser issue, it’s the small ratchet built into the chain tensioner not catching at shutdown. Depending on how the cam lobes and valves are oriented, the cam might want to turn backwards at shutdown. If the tensioner ratchet engaged the chain would prevent that, but since it doesn’t, the tensioner is allowed to compress, which makes slack on the other side of the chain. Keep in mind the other side is the "drive" side.. it's the crank pulling on the cams. Now when you start the engine, that slack lets the cams and chain slap around until there is enough oil pressure to extend the tensioner and take up slack on the non-driven side of the chain, making things quiet.
Supporting this theory is the fact that the updated tensioners have an improved ratchet design.
That is a different and less serious issue. It may be related, but plenty of 3URs that haven’t had the timing chain “slap” (that sounds like a rod bearing) do get the minor tick. It being cyclical is the hallmark here. And so far it seems to be harmless.
Supporting this theory is the fact that the updated tensioners have an improved ratchet design.
That is a different and less serious issue. It may be related, but plenty of 3URs that haven’t had the timing chain “slap” (that sounds like a rod bearing) do get the minor tick. It being cyclical is the hallmark here. And so far it seems to be harmless.
Last edited:
