I’ve heard of engines with compression rings (the high or low tension rings) and oil control rings. Haven’t heard of a motor with both high and low tension rings. It’s typically either or with the design of the motor. Modern motors are trending towards the use of low tension rings to improve efficiency when new, although some low tension ring motor designs end up with piston slap or oil consumption as a consequence with age and mileage. I don’t know what kind of rings the 1UR-FSE was designed with. May very well be the low tension variety.
since you’re intent on rebuilding the motor, ask the mechanic to pay close attention to the crankshaft bearing surface on the failed rod bearing, and the condition of the rod with the failed bearing. Use a plastigage to verify tolerances when selecting a bearing. Use plenty of assembly lube when reassembling and flush the motor oil out several times to try to get any circulating shavings out of the engine. Inspect the oil pump and pickup screen, clean as well as possible. Good luck to you.

 

“all LS460s sound like that, it’s the direct injection fuel injectors”
had to say it.

 

Damn man , you have had horrible luck with this car it's one thing after another.

Unless you were redlining the engine fir a period of time this shouldn't happen on a Lexus V8

valve springs , head work maybe, but the bottom ends are bulletproof I think you are the first person this has ever happened too.

I agree with trying to fix the minimum as possible, but I'd also start searching for local engines as well to see whats around.

in all honesty you should sell this car as soon as it's fixed it's been really bad to you over and over.

 

Yes, low tension rings are what we unfortunately deal with now due to fuel consumption reduction attempts (trying to reduce friction).

When this ^^ happens, when the oil control rings and compression rings fill up with soot and carbon, they would usually be able to expand out of their piston lands due to the higher tension - lower tension rings aren’t able to do that - so, picture a oil control ring (the lower ring) being covered in soot, not allowing the oil to be scraped off the wall and allowing it to flow past the control holes between the oil ring, and flow/fall back down to the crankcase...this causes the oil to flow right past the rings and burn (because the rings are “stuck”, they can’t come out, they can’t expand out of their lands, they are so stuck in there that you can’t even take them out by hand when you remove the pistons) It takes a while for this to happen...usually starts happening after 120,000 miles or so. Extended drains don’t help, or poor quality oil, lack of top tier fuel, poor maintenance, etc. Piston soaks might help (occasionally). Direct injection doesn’t help matters either as rings become even more sooted because of the pressure of the fuel pressing down onto the rings. Some people may never see these problems because they take such great care of their cars from the very beginning, but some, even if they do, will still experience this. The oil consumption due to the low tension rings.

I didn’t read what your mileage was, but if it’s in that 100,000-120,000 mile range...and if you’re going to have your crankshaft removed and machined...might as well see if they can replace the pistons while they’re in there. Just my opinion.

But if you can get those bearings replaced for $1,200 bucks?? Yeah, I’d do that too. I just know that around where I am, that would never happen. That would be a $3,000-$4,000 dollar job around here. That’s why I’d definitely go with a used engine (around here they’re not much money).

 

I have built many engines since the 60’s and the shop manual for an ls 460 is 6000 pages.

i am good BUT the learning curve would be scary.

I would roll the dice on a used engine first.

Motor must come completely apart and be gas cleaned. And I doubt you will get everything out of it.

its a stern chase now. Not for the faint of wallet or patience.

Sorry. Its fatal imo.

 

There's no way I'd tear into that engine. No way. Swap and be done with it.

 

it’s been torn into before so who cares.... also it’s not expensive to do so why not will see today if it’s even repairable and will let you guys know.

you guys are have no spirit of adventure lol however don’t blame you the art of repair has mostly disappeared in the US and Canada and at the prices why bother. But for the money why not I may decide otherwise if I find some great low miles cheap engine but the cheapest I’ve seen is 1600 or 1800...

 

Hey I'm all about the spirit of adventure...with the caveat though that doing unpleasant stuff over and over again isn't adventure to me. It's hell. I suspect that the Lexus techs who did engine work on your car before screwed something up ...hence where you are today. Ostensibly, a Lexus-certified mechanic *should* know what they're doing but clearly, that is suspect. I just have zero confidence that anyone is likely to be able to get this right over the long haul. Yes, you may pay more up-front for a engine swap but you're done after that. No more worrying about the next time it goes bad on you from something they missed. To me, that level of peace of mind is more than worth the extra expense.

 

ok guys I’m considering an engine swap but I need some help. It’s not easy to find a good example.

so I need specific answers if possible.

if I am only looking for 2007 engines it’s going to be hard to find a low mile example, since I am able to reuse a lot of the parts from my car I essentially knit need the block part of the engine ....

when it comes to fitment eBay listings only list 07 will fit up to 08, 09 to 12 etc. So my question is ..considering what we know above, up to what year can I go ? Also can AWD engines be in the running or are they substantially different? Cant just pop sone bits off? Here you need to put aside the US bias and stick to what’s technically sound and possible, do not consider labour etc

thanks guys !

 

I’m thinking pretty much any 07-17 LS460 engine will bolt up, just be prepared to remove the oil pan (AWD) and strip it down to a long block if necessary.

 

so what happened to your spirit of adventure? I thought you’d have your mechanic clean up the crank and rod journal of the affected rod with emery cloth, install one rod bearing, flush the engine oil a few times and call it good

 

read considering ill decide once I’ve done the math it depend on price and what I manage find in terms of engine. I’ll post more photos of the torn down engine later

 

I’m cheering for you, man! Either way keep us posted.

 

In the meantime here are some photos the mechanic sent me, excuse the blurry shots.

Comment away:

 

Is that a crack in the crankshaft?