Sheared valves after timing belt replacement?
#1
Driver School Candidate
Thread Starter
Sheared valves after timing belt replacement?
Hey all,
I purchased my 2005 a couple months ago with 125K miles. I saw no evidence of the timing belt and water pump ever being replaced, so I decided to get it done, just to be safe. Took it to my local shop (which is very highly rated and trusted). Anyway, I get a call that afternoon from the owner of the shop (uh oh!).
He said they got the belt on, manually turned the engine two full revolutions, everything looked, felt, and sounded perfect. The timing was right. Upon cranking it up; however, something didn't sound right. After opening up the engine, they discover there are two valves on the driver side head stuck in the down position and that they would need to inspect things in more detail. The next day, they call and let me know they're sending both the driver and passenger side heads to a machinist for inspection and replacement. All of the values on the driver side will be replaced and the passenger side will be heavily cleaned and inspected. If any valves on that side need to be replaced, they'll go ahead and replace them. They are covering the cost of this additional work and are warranting the parts for 2yrs/24,000.
It's been a few days, so I called the shop owner again today. I asked about the possibility of the valves hitting the piston(s) and being bent. He then said they were sheered, not bent.He said they did some research and found where this had happened to other Lexus owners after a timing belt replacement. He also mentioned the valves had a great deal of carbon build-up. My questions to everyone are: Has anyone heard of such a thing happening (I don't see anything about it on the net anywhere)? Is there anything I need to bring to the shop's attention (i.e. Are there special considerations to replacing the timing belt on the 4.3)? Could there be damage to other areas of the engine? I'm very grateful they're covering these costs, I'm just concerned about the longevity of the engine at this point. Perhaps my concern is invalid.
The owner mentioned in both of our phone calls that the work they did didn't play a role in what happened. While everyone at the shop has been extremely professional, kind, and empathetic, I just have a hard time believing that their work is unrelated. I mean, the vehicle was operating perfectly fine when I dropped it off. Perhaps we'll never know if it was human error, or a true coincidence.
I purchased my 2005 a couple months ago with 125K miles. I saw no evidence of the timing belt and water pump ever being replaced, so I decided to get it done, just to be safe. Took it to my local shop (which is very highly rated and trusted). Anyway, I get a call that afternoon from the owner of the shop (uh oh!).
He said they got the belt on, manually turned the engine two full revolutions, everything looked, felt, and sounded perfect. The timing was right. Upon cranking it up; however, something didn't sound right. After opening up the engine, they discover there are two valves on the driver side head stuck in the down position and that they would need to inspect things in more detail. The next day, they call and let me know they're sending both the driver and passenger side heads to a machinist for inspection and replacement. All of the values on the driver side will be replaced and the passenger side will be heavily cleaned and inspected. If any valves on that side need to be replaced, they'll go ahead and replace them. They are covering the cost of this additional work and are warranting the parts for 2yrs/24,000.
It's been a few days, so I called the shop owner again today. I asked about the possibility of the valves hitting the piston(s) and being bent. He then said they were sheered, not bent.He said they did some research and found where this had happened to other Lexus owners after a timing belt replacement. He also mentioned the valves had a great deal of carbon build-up. My questions to everyone are: Has anyone heard of such a thing happening (I don't see anything about it on the net anywhere)? Is there anything I need to bring to the shop's attention (i.e. Are there special considerations to replacing the timing belt on the 4.3)? Could there be damage to other areas of the engine? I'm very grateful they're covering these costs, I'm just concerned about the longevity of the engine at this point. Perhaps my concern is invalid.
The owner mentioned in both of our phone calls that the work they did didn't play a role in what happened. While everyone at the shop has been extremely professional, kind, and empathetic, I just have a hard time believing that their work is unrelated. I mean, the vehicle was operating perfectly fine when I dropped it off. Perhaps we'll never know if it was human error, or a true coincidence.
#2
Nope. Some one over there screwed up, plain and simple. At least they are owning up to it.
Never heard of a valve suffering shear force before. I would ask for the parts back when they are finished with the job. If you get them back could you post some pictures...
Never heard of a valve suffering shear force before. I would ask for the parts back when they are finished with the job. If you get them back could you post some pictures...
Last edited by Gronemus; 12-06-16 at 10:27 PM. Reason: Clarify request
#3
How did the valves shear off? Physically - I find that improbable but I could be wrong. If the engine heads are at a machine shop, ask for it's name and go over - take a few pics. There's not a whole lot of detail in saying they sheared off - where did they shear off? Did the other valves hit the pistons? Are they checking for damage to pistons? Did the valves shear off below the stem or where?
Carbon build up and valve shear do not make sense as well. I still like the shop for standing behind their work but now it's time you took the matter in your own hands and ensured it is being put back together like original. The machinist will be able to tell quite a bit from looking at the heads.
Carbon build up and valve shear do not make sense as well. I still like the shop for standing behind their work but now it's time you took the matter in your own hands and ensured it is being put back together like original. The machinist will be able to tell quite a bit from looking at the heads.
#4
They messed up somewhere and are trying to cover their *** thats why they are eating the costs. Car doesnt go from running perfect to sheering valves out of nowhere unless the timing belt was installed incorrectly. If they cant do a timing belt job id question them putting it back together properly after having both heads off.
#5
Lexus Champion
The LS430 has an interference engine, and the timing belt is the only thing that keep the "Interference" from happening. Well, in your case, "Interference" occurred. Before you sign off on the repair, please be sure to witness the compression test. Proper compression pressure range is 142-178 PSI. Pressure for the 8 cylinders should not vary significantly (Max and Min pressures are less than 10% apart). The "Interference" can damage the pistons, piston rings, valve guides, and a number of other parts that will impact compression pressure.
#6
Pole Position
This result could only occur from negligence. The 3UZ-FE engine is an interference engine. It's a quad valve overhead. If a camshaft is out of correct timing, a piston will hit two or more of the valves on the stroke. (It will hit at least 2 valves, not one because each cylinder has 2 intake and 2 exhaust valves). The piston will bend (not sheer) the valve stem. In your case, two valves were stuck in the "down position" - based on that description, the valve stems bent close to the point of contact with the piston, then got crushed (perhaps their description "sheered") by the constant hitting of the top of the piston. The hydraulic internals of the valve lifters could also be damaged, as well as the piston in the one cylinder where contact with the valves occurred. Hopefully, the camshaft itself wasn't damaged. The 3UZ-FE is an aluminum engine.
You say they are "warranting the parts"... the real cost of any repair is not the costs, but the labor, and if it were to fail, you'd have a tough time pinpointing that the cause is the replacement parts they installed.
Ask to see the valves that were replaced. Ask for the "research" the shop did where this happened to other Lexus owners. (To my knowledge, this has only happened to a few Lexus owners who have the timing belt break with the 3UZ-FE engine running, or who have improperly installed a timing belt.)
Edit: Wrote well-before refreshing and seeing rkw's post.
You say they are "warranting the parts"... the real cost of any repair is not the costs, but the labor, and if it were to fail, you'd have a tough time pinpointing that the cause is the replacement parts they installed.
Ask to see the valves that were replaced. Ask for the "research" the shop did where this happened to other Lexus owners. (To my knowledge, this has only happened to a few Lexus owners who have the timing belt break with the 3UZ-FE engine running, or who have improperly installed a timing belt.)
Edit: Wrote well-before refreshing and seeing rkw's post.
#7
Instructor
I don't think the shop is telling you the whole truth. Carbon buildup will not cause that. There is no way they hand rotated the engine and then there was a problem at startup. The fact that all the damage is on one side tells you that that cam was not timed correctly. If there was enough force to actually break the valves there was definitely enough force to crack a piston as well. The fact that they screwed up just the timing belt swap would leave me zero confidence in them reassembling the top on the engine. Each pair of cams must be timed perfectly to each other mechanically and then the pairs timed with the new timing belt. Not to mention the heads must be assembled twice to correctly measure and adjust the valve clearances which will be off with new valves and a valve job. There are about 50 different shim thicknesses available (each a special order part) to ensure the correct tolerances.
If this was my vehicle I would source a used engine with a known lower mileage and have them buy and install that. I would trust a factory sealed used engine much more than one that they attempted to rebuild. Are they going to use factory Lexus head gaskets, new head bolts, correct torque specs and sequences, etc? Reinstalling heads on these engines correctly is much much harder than a simple timing belt service.
If this was my vehicle I would source a used engine with a known lower mileage and have them buy and install that. I would trust a factory sealed used engine much more than one that they attempted to rebuild. Are they going to use factory Lexus head gaskets, new head bolts, correct torque specs and sequences, etc? Reinstalling heads on these engines correctly is much much harder than a simple timing belt service.
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rseifer (12-26-16)
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#8
Pole Position
Agree with 911LE ... though I wouldn't have the same shop install the used engine. It's a personal choice, but if it were me, I'd have it towed to a Lexus or Toyota dealer and have them do a complete diagnosis and the necessary repairs. Then I'd hold your local shop responsible for the costs to repair the damage they caused. Sorry you had this regretful experience ...
#9
The owner mentioned in both of our phone calls that the work they did didn't play a role in what happened. While everyone at the shop has been extremely professional, kind, and empathetic, I just have a hard time believing that their work is unrelated. I mean, the vehicle was operating perfectly fine when I dropped it off. Perhaps we'll never know if it was human error, or a true coincidence.
Like everyone else has said, this is BS.
They are probably setting the stage for you to "meet them in the middle" on the repair costs by pretending you were partially at fault. Obviously, you don't pay a cent for this repair. One of their techs screwed up badly.
I would also agree that it would be much better for them to simply give you the money they would spend trying to fix it and instead find a used, replacement engine and have another shop perform the work, but my guess is they aren't going to go for that.
But the last thing I would want from a shop that screwed up something as straightforward as replacing a timing belt is then attempting to rebuild my engine.
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rseifer (12-26-16)
#10
Instructor
I would go to the shop and see if you can take some pics of the damage. It sounds like the shop is going to try to avoid paying for their mistake. Document everything you can in case they put up a fight. If the valves did indeed "shear off" then the engine is destroyed. The head of the valve has no place to go and it gets repeatedly hammered into the head, piston, and cylinder wall. Google some pics of a broken valve to see for yourself.
Last edited by 911LE; 12-07-16 at 11:40 AM.
#11
I would go to the shop and see if you can take some pics of the damage. It sounds like the shop is going to try to avoid paying for their mistake. Document everything you can in case they put up a fight. If the valves did indeed "shear off" then the engine is destroyed. The head of the valve has no place to go and it gets repeatedly hammered into the head, piston, and cylinder wall. Google some pics of a broken valve to see for yourself.
#12
Moderator
We'll have to see what the OP responds with on this one. I would hope he went over to the shop today to see his engine and take a look at the pistons. I can't believe what some shops would do to cover themselves. I read so many posts like "I would never have the stealership work on my car, they charge too much!" or what about "Why go to the dealer when you can go to an indy shop and save some money?<br /><br />This is exactly why I go to the Lexus service center to have my car worked on. Not to say they don't make mistakes, but I don't believe they would try to pull a story like this one...<br /><br />I hope this get's rectified correctly...
#13
Lexus Champion
We'll have to see what the OP responds with on this one. I would hope he went over to the shop today to see his engine and take a look at the pistons. I can't believe what some shops would do to cover themselves. I read so many posts like "I would never have the stealership work on my car, they charge too much!" or what about "Why go to the dealer when you can go to an indy shop and save some money?<br /><br />This is exactly why I go to the Lexus service center to have my car worked on. Not to say they don't make mistakes, but I don't believe they would try to pull a story like this one...<br /><br />I hope this get's rectified correctly...
OP, hoping for the best in this bad situation.
#14
Lexus Fanatic
Sorry to hear about this....I'm starting to feel skeptical myself. Was not able to find a "specialist" for my Nissan, having the same trouble for Lexus. Found a true "specialist" for BMW. To illustrate, had Pilot Super Sports mounted/balanced for $90, went to pickup my car and it was being washed by hand inside. Big turbo kits on display, talk all day long with techs about mods etc.
Today, I called a so-called Japanese specialist, 5 star on Yelp, pics of all Japanese cars being fixed. "Hi, do you install customer parts?" "No." "Ok, well, I have a Lexus LS430 and want to get the lower control arm bushings replaced, how would you do it?" "We don't see too many cars like yours, we'd have to see it in person first." CLICK. Not really, because of caller ID, but what kind of Japanese specialist is that? My hunch is that folks who work on Japanese cars are not enthusiasts, they are a means to an end, a paycheck. And so it's not easy I guess to find an indie at least from my experience...and the above has a perfect Yelp rating. Others have tales where they ripped off the customer or charge the same as the dealer...my point is my car is not for you to learn on, you're supposed to be expert and ASE certified blah blah blah
Today, I called a so-called Japanese specialist, 5 star on Yelp, pics of all Japanese cars being fixed. "Hi, do you install customer parts?" "No." "Ok, well, I have a Lexus LS430 and want to get the lower control arm bushings replaced, how would you do it?" "We don't see too many cars like yours, we'd have to see it in person first." CLICK. Not really, because of caller ID, but what kind of Japanese specialist is that? My hunch is that folks who work on Japanese cars are not enthusiasts, they are a means to an end, a paycheck. And so it's not easy I guess to find an indie at least from my experience...and the above has a perfect Yelp rating. Others have tales where they ripped off the customer or charge the same as the dealer...my point is my car is not for you to learn on, you're supposed to be expert and ASE certified blah blah blah
#15
Lexus Champion
OP, do you know if you were getting a new tensioner?
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rseifer (12-26-16)