OP, do you have any pics of the damage? Coincidentally, mine is also a 2002 LC with 159k on the clock. But my timing belt has been done already. Good luck with everything.
Air cleaner blew up, won't start now. Oh god...
- Thread starter LCtygrys
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This is what I'm wondering. I get that a belt can break at any time, but I wonder if it's ever been done.
Not sure exactly what you/he mean by the sprocket is "off", but that doesn't sound typical of the belt breaking first.
So far, I'm guessing the problem started with a mechanical failure in one of the heads and that lead to the broken belt, not the other way around. There's just too much non-timing belt type of damage? intake valve failure? Cam bearing failure? Cam pulley failure? Pics would be interesting.
Some things you need to know if you need to go reman on a 4.7. The LC/LX engines are cast iron block and forged connecting rods. If you use a Lexus car engine it will have a less durable aluminum block. The Tundra uses a cast iron block but has less durable cast connecting rods. It might be of little difference to you, but it should be known.
I don't know right now, but I'm sure someone here knows how to identify what sort of 2UZ one might see in front of them.
I don't know right now, but I'm sure someone here knows how to identify what sort of 2UZ one might see in front of them.
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- #26
Any updates?
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- #28
Ok here's some pictures. Oh boy...
Wow, with the cam sheared off like that I'd start motor shopping. I do wonder what went on in that bank though, if the shaft simply was bad and sheared or if something stopped the cam or cam gears inside the head.
Thanks for the updates, sorry for your troubles.
Thanks for the updates, sorry for your troubles.
all i can add is wow...
Yikes! I wonder if just replacing the top end and keeping the short block might work. There are a lot of 4.7's out there (if they'll interchange).
Cruiserdrew
On the way there
I think those pictures answer the interference engine question!
Very impressive carnage.
New motor time.
Very impressive carnage.
New motor time.
I'm dense, but don't get how that means interference engine. If the belt broke first, I don't get how a valve interference would shear the cam shaft, since the belt wouldn't be holding it fixed. If something else let loose first and froze the shaft, you'd think the belt would give before the shaft? I don't see how the shaft would shear with the force of an unbroken belt against interfering valves? Again, I'm an engine internals newbie, so maybe I'm missing something. But it seems more likely that something caused that cam to sieze first, then broke the belt, causing misfire, etc.?
Still inconclusive. Anyone in guessing until the heads are removed, and then opening up the oil pan if the heads don't tell a story.
Bummer this happened to you, sorry.
Bummer this happened to you, sorry.
Is that a designed shear plane that I see? Looks like it fractured there because it was designed to fracture there. Or are those bite marks from a press trying to get it out?
I wonder if the gear kept spinning but the cams stopped? The cam sensor pickup is on that side, right? If so, the ECU may have thought everything was fine and it could have been pumping air/fuel mix through an open valve into the intake which could explain the explosion on the intake side.
I wonder if the gear kept spinning but the cams stopped? The cam sensor pickup is on that side, right? If so, the ECU may have thought everything was fine and it could have been pumping air/fuel mix through an open valve into the intake which could explain the explosion on the intake side.
I'm with you on this. I think you're going to find a problem deeper in. That's an enormous amount of back pressure to splode the airbox like that.
I'm going to chime in here and say stay away from enginehaus in WA. I Have a few customers who have installed their engines and they do not last long. My opinion for what it's worth is to buy a good used engine from a reputable dealer.
I had a timing belt failure last year and went through the same thing you are going through with finding out if it is an interference motor or not.
I don't know about vvti cars, but for non vvti it is NOT an interference motor. I slapped a new timing belt on my 98 with all the pulleys and bearings and she fired right up. I was able to spin the cam gears with a ratchet to confirm that there was no damage. If there is, you will feel it. Even Slee in golden, the land cruiser experts who I had diagnose the car initially told me I needed a new motor.
I don't know about vvti cars, but for non vvti it is NOT an interference motor. I slapped a new timing belt on my 98 with all the pulleys and bearings and she fired right up. I was able to spin the cam gears with a ratchet to confirm that there was no damage. If there is, you will feel it. Even Slee in golden, the land cruiser experts who I had diagnose the car initially told me I needed a new motor.
I agree with re_guderian that this damage does not lead to the conclusion of an interference engine. Thanks GDenver for posting - I would like to see one post where someone had a broken belt lead to bent valves.
It is an interference engine, the valves can contact the top of the pistons. Just because the timing belt fails, does not necessarily mean it will interfere, because the cams might land on the all closed position before the pistons hit the top of the stroke.