VF40 goes Kaboom

[MilesA]

...So what else do I need to do to fix this issue before I just replace the turbo?

 

A lot of what you'll need to know is covered in this sticky post:

 

http://legacygt.com/forums/showthread.php/turbo-failure-wiki-173358.html

 

If you remove the oil pan, you'll see the rest of the story without having to wait on the lab. Once metal particles have gotten into the oil passages, you may not be able to save your shortblock.

 

If you are changing to a different turbo, you will need a tune to be safe.

[grovlet]

Oil system flush should be high up on your list.

 

Along with new oil system parts - lines / cooler....

 

And by the looks of that turbine wheel - I wouldn't bother..... There is ZERO doubt you've sent debris throughout the oil system - and therefore the bad news #YNNSB#

 

I replaced my turbo 2x over - 1st replacement went 20K - #2 = 10K

 

After #2 - New ShortBlock (and New VF52) = Turbo went in 800 miles - replaced that with hope - 750 miles later = blown and took out new ShortBlock:mad:

 

Finally replaced heads and 2nd new ShortBlock + another VF52:eek:

 

Turned out the heads were the issue all along = must have had a blocked oil passage from one of the blown turbos

 

But read the sticky - you're pretty much guaranteed to at least need a ShortBlock - and maybe heads = total rebuild in order:eek:

 

And as noted - I thought the same as most early on = ahh can't be true - but yup - I'll join the crowd now and agree - blown turbos in this car are bad news for the engine and heads

Edited August 12, 2017 by grovlet

[Max Capacity]

Agree, you need a new short block and have the heads rebuilt by a machine shop. Have them clean the valve covers, oil pan, any part they can. Make sure your intake manifold is clean.

 

get a new oil pump and oil cooler.

 

replace some other hoses as well, heater and oil return from turbo.

 

read my click here link for ideas.

[MoarBoost]

Well nuts. that's not the news I was hoping for... That sticky was definitely the first thing I read through but thanks for the advice. Definitely worth going back through again.

[MoarBoost]

FWIW, here's the turbo teardown.

 

http://i.imgur.com/JPYiq4y.jpg

 

Starting on the compressor side, even before taking off the comp cover it's apparent that the comp wheel blades are not as they should be. There's definitely been some shaft motion:

 

http://i.imgur.com/v7k8lQ9.jpg

 

Taking the comp cover off, it actually looks like it's in pretty good condition. It's not as marred up as I would've expected

 

http://i.imgur.com/ODByNSz.jpg

 

The compressor wheel on the other hand is pretty messed up. The blades are bent, but no big chunks seem to have broken off (that doesn't mean there aren't aluminum filings though)

 

http://i.imgur.com/W90cai5.jpg

 

Taking the compressor nut off was definitely a b!tch, but that's to be expected. The torque specs have to be high in order to get proper shaft stretch to clamp the comp wheel and keep it from rotating with respect to the balance cuts on the shaft and turbine wheel assy.

 

http://i.imgur.com/fJ0EZOG.jpg

 

Finally getting the comp wheel off, the backface of the comp wheel shows where it was rubbing on the outer diameter near the exducer. The comp wheel was obviously hitting the comp cover inlet and the backplate wheel pocket.

 

http://i.imgur.com/29GcrxO.jpg

 

Four torx bolts later and the backplate is off. The little bit to the left is the flinger, which acts as a tightly toleranced spacer to keep the comp wheel in the right position, axially, and as a piston ring "housing" which is what makes a labyrinth seal to keep oil from seeping from the bearing housing to the compressor stage. There's one on the turbine side as well which I'll show later. A lot of modern turbochargers will have two piston rings on both the compressor and turbine side, instead of just one.

 

http://i.imgur.com/pljpXNq.jpg

 

Next up, the turbine side. Then the bearings.

[MoarBoost]

http://i.imgur.com/XLmpnYF.jpg

 

The new technology from IHI is the quick connect turbine wheel. Great job, guys.

 

Removing the V-band, it still looks like it's in good shape. There was some oil residue buildup on the inner bottom side though (can't really see in this photo)

 

http://i.imgur.com/AoXu2K7.jpg

 

The turbine housing was definitely frozen on to the bearing housing. A few hits with a hammer and it was persuaded to come off. Most obvious is how much the turbine wheel has gouged out the turbine housing contour. That housing is absolutely f*cked and is completely irreparable. In this photo you can also see the orientation roll pin that mates with the bearing housing, and if you look closely, you can see a chunk of turbine wheel lodged near the volute tongue (where the smallest part of the volute meets the largest).

 

http://i.imgur.com/WTpfzOR.jpg

 

Back to the turbine wheel

http://i.imgur.com/ullI6y5.jpg

 

There seems to be a lot of material that was removed from what looks to either be the shaft or the turbine wheel, where they are welded together. It looks like the larger diameter that used to have a piston ring groove is part of the turbine wheel since it looks like there is still part of the shaft still inside the turbine wheel shaft pilot.

 

No wonder why the heatshield is so damaged. It is interesting that they have such a complex contour to the stamping, though.

 

http://i.imgur.com/HG2RcLa.jpg

 

On the bearing housing, you can see where the turbine wheel was hitting the edge and damaging it.

 

http://i.imgur.com/12PuXnd.jpg

 

So, I picked up a used VF52 a few days ago and it's interesting what design changes they made between the different versions. It's probably obvious, but below, VF40 on the left, VF52 on the right.

 

http://i.imgur.com/lW52y27.jpg

 

Major design updates seem to be a larger volute (larger A/r) larger turbine wheel (I still need to measure the housings) and improved wastegate position. On the VF40, as the WG opens, you can almost visualize how the exhaust will continue with its downward vector and as the WG opens, hit the part where the valve arm is welded to the shaft. The VF52 is definitely a better design since the WG flow is unimpeded by the WG components themselves. This is definitely the reason for the super long WG bushing (silver looking cylinder in-line with the axis of rotation of the WG).

 

next up: bearings

[MoarBoost]

Now for the fun stuff.

 

With the backplate off, you can see (one of the) thrust bearings screwed in place by three little PITAs. I think I remember those also being torx bits... but it doesn't matter. Those guys aren't coming out with conventional methods.

 

http://i.imgur.com/PQH97gg.jpg

 

A regular old drill bit made quick work of these. The picture below shows what's under the compressor-side thrust bearing, which is the thrust washer in the middle, and at the 4:00 position in the pic is the oil feed hole to the thrust bearing not pictured.

 

http://i.imgur.com/JQrQgFg.jpg

 

This is the compressor-side thrust bearing. The 1:00 position is the part that is pointing upwards. the semicircle groove and the little pockets are oil pockets that also have tiny holes that feed oil straight to the bearing surfaces...which have been completely eroded away. You can still see the axial oil feed holes though. The shiny part on the inside is where there are supposed to be little ramps which are the actual bearing surfaces. We'll see those on the turbine-side thrust bearing.

 

http://i.imgur.com/iOASwYf.jpg

 

Getting the rest of the bearing components out was a little difficult. I had to find a punch and drive them out from the turbine side little by little. And here they are:

 

http://i.imgur.com/yWuLcvI.jpg

 

In the above picture, from left to right are the thrust washer, turbine-side thrust bearing, compressor-side journal bearing, spacer and turbine-side journal bearing. On the bottom are the turbine-side piston ring and a spring-ring.

 

Below, the thrust washer (silver) is the component that spins with the rotating assembly. This component is clamped between the flinger and the step on the shaft and this part transfers all of the thrust load.

 

The brass looking part is the other thrust bearing. (see how those bearing ramps are still visible?)

 

http://i.imgur.com/dN30JV0.jpg

 

The journal bearings (below) actually seemed like they were in great shape. They were difficult to get out because that spacer is also pressed in. The hole in the middle is for the oil drain which has to be oriented downward.

 

http://i.imgur.com/vn3asgs.jpg

 

The piston ring, I actually found in the oil drain cavity of the bearing housing (not good.) The spring ring is probably interacting with a small groove in the bearing housing which keeps the journal bearings from moving axially.

 

http://i.imgur.com/rcVrGjl.jpg

 

Taking a look at the shaft, the bearing surfaces actually look quite good, too. Measuring both bearing surfaces and the shaft in the middle produced decent numbers. Both bearing surfaces measured 0.3155" (8.0137mm). The center section of the shaft, which should still be new part spec is 0.3170" (8.0518mm)

 

http://i.imgur.com/TyLAEcu.jpg

 

http://i.imgur.com/4JoDg7g.jpg

 

The part of the shaft inside the comp wheel measured 0.21" (5.334mm). Reading through the sticky on turbo failure, it's stated that the shaft is 4mm, which I just don't see anywhere.

 

But anyway... That's the turbo. More on why it actually failed, plus why it was making the noises it did.

[Max Capacity]

Here's my VF40 which just began to kiss the housing. Notice any difference ?

 

http://i185.photobucket.com/albums/x40/92Si/DSCN4598.jpg

[MoarBoost]

looks pretty darn similar. The wear marks are even in the same location on both housings.

[Merc6]

Yeah I never tore down my VF40, it was broke like that with turbine separation. I ended up selling it to a local who shipped it to BNR. Got a 46 from another local who totaled his Shrek B in the snow. Thought I cleaned everything and kept the oil cooler and oil pump. 2000/3000 miles later engine gone and 46 contaminated. Currently on block 2 and JmP VF52 while replacing the parts I blew off from changing the 1st time.

[Max Capacity]

looks pretty darn similar. The wear marks are even in the same location on both housings.

 

I see a lot more scuffing on the radius on yours.

[JmP6889928]

I've been reading this thread. Perhaps, it would be better if I don't comment.

[Max Capacity]

I've been reading this thread. Perhaps, it would be better if I don't comment.

 

I've been wondering if your still around.

 

OP this is the resident expert on rebuilding turbo's. if you have any questions, this is the guy to ask.

 

We recommend to all members to have him rebuild there turbo's.

[MoarBoost]

I've been reading this thread. Perhaps, it would be better if I don't comment.

 

Please, by all means comment! I'm looking for any and all feedback!

 

OP this is the resident expert on rebuilding turbo's. if you have any questions, this is the guy to ask.

 

We recommend to all members to have him rebuild there turbo's.

 

Thanks for the introduction!

Edited August 14, 2017 by MoarBoost

[JmP6889928]

OK....Sorry if I sound like a downer.

 

1. Do NOT put another turbo on that engine and run it until Blackstone sends you back results. You're most likely far into needing a new shortblock. You drove it so far that I'm surprised it even made it to the end location.

2. The disassembly of the turbo shows that it definitely starved for oil, meaning that you have other issues even before the turbo grenaded. You are most likely needing heads at this point too because of all the junk circulated inside.

3. The turbo internals rely on the pressure of the oil to be correct as well as the flow and starving means that both the banjo filter was most likely plugged and probably you have an oil pump issue too-meaning you need to basically scrap the engine.

 

I've not seen one where someone drove it almost 100 miles with a broken shaft and have it flush out. If you install your almost new VF52, it will not go very far and you'll be in the same boat you are now. The larger IHI turbos can break the shaft just as easily as the VF40/46 can and you'll be even further down the road with money invested and nothing to show for it.

 

Your best bet is to find a decent used engine that has the turbo on it already. Install it and drive it for 10-12K miles and once you know it's healthy, THEN worry about the VF52, but if it were me, I wouldn't take a chance on assembling it as is and driving it across the street. There is junk buried inside your engine that you'll never find.

[Merc6]

OK....Sorry if I sound like a downer.

 

1. Do NOT put another turbo on that engine and run it until Blackstone sends you back results. You're most likely far into needing a new shortblock. You drove it so far that I'm surprised it even made it to the end location.

2. The disassembly of the turbo shows that it definitely starved for oil, meaning that you have other issues even before the turbo grenaded. You are most likely needing heads at this point too because of all the junk circulated inside.

3. The turbo internals rely on the pressure of the oil to be correct as well as the flow and starving means that both the banjo filter was most likely plugged and probably you have an oil pump issue too-meaning you need to basically scrap the engine.

 

I've not seen one where someone drove it almost 100 miles with a broken shaft and have it flush out. If you install your almost new VF52, it will not go very far and you'll be in the same boat you are now. The larger IHI turbos can break the shaft just as easily as the VF40/46 can and you'll be even further down the road with money invested and nothing to show for it.

 

Your best bet is to find a decent used engine that has the turbo on it already. Install it and drive it for 10-12K miles and once you know it's healthy, THEN worry about the VF52, but if it were me, I wouldn't take a chance on assembling it as is and driving it across the street. There is junk buried inside your engine that you'll never find.

 

 

Yep, took shortcuts and paid for it. Trying to rush the car back on the road doesn't work out well in the end unless you are the PNW folks here who seem pull at least 1 engine a weekend. I semi wish lived that way but I like my gun rights. Most folks this way are buyers and not builders.

[MoarBoost]

Yeah, that definitely correlates with what everybody else is recommending. Everyone, thanks a lot for the advice. I've been partially expecting this outcome and as soon as I parked the thing last, I was on the hunt for a replacement motor.

 

Back to the analysis though...

 

My stupidity plays a big role in this as well. For reasons outside of the scope of this thread, I neglected this car and ran it over 12k miles on the same oil, without so much as even checking the level. *beat-head-against-wall-emoji* Please don't berate me too much. I know how idiotic that is (obviously... I'm already paying for it) but I'm trying to learn from my mistakes, learn something about this car, and get it back on the road... because I absolutely love my LGT (even when it's on jackstands).

 

Down to what I think happened...

 

There were three distinct phases of failure, in my mind, marked by the following symptoms:

1. CEL comes on with flashing cruise control

2. hear "vhoop" noise and little to no throttle response at-speed

3. tin-can-of-bolts sound coming from under the hood after starting from a stop

 

 

1. CEL codes were:

P0102 - MAF circuit low input

this one makes sense. Compressor isn't pulling the amount of air expected.

P0011 - Camshaft Position - Timing Over-Advanced (Bank 1)

OK. So if boost is low, that means air/fuel ratio is low, meaning the engine is expecting more oxygen and is running abnormally rich.... Nope, I think there's an easier answer to this: As best I can see from ClimberD@HexMods informative post, the AVCS (variable valve timing) shares the same oil feed circuit as the turbo. The AVCS is actuated with oil pressure. If the turbo is getting starved of oil, chances are the AVCS is too, which could result in a forced timing change.

P0113 - Intake Air Temp Circuit High Input

not sure about this one. This means that either the intake air temp sensor is going, or it is somehow linked to the MAF circuit input (P0102). It sounds like these two codes often show up together.

P0021 - Intake Camshaft Position Timing - Over-Advanced (Bank 2)

I believe this just means that Bank 2 is receiving the same faulty timing advancement from the AVCS, although I've been trying to find more information about how the AVCS actuates both banks. I've come up a little short here. But perhaps that's because I haven't torn apart an EJ before, I don't know.

 

My thinking is that the combination of low engine oil quantity and probably partially clogged banjo bolt filters started starving the turbo of oil causing the thrust bearing to start to wear. The rotating assembly would still rotate and produce boost, but it was a lot higher friction since there wasn't any layer of oil between the thrust bearing and thrust washer. (keep in mind, the CELs were pulled after the car was in the garage, partially disassembled)

 

 

2. the "vhoop" noise I believe, was the wastegate actuator rapidly losing pressure, because the compressor was rapidly being ground to a halt because of the thrust bearings wearing down. If the turbo is being starved of oil, the bearings that take the thrust in the compressor direction are probably going to fail first, since that is the direction of the thrust load under normal operation.

 

Minutes after I started hearing the "vhoop", I lost boost. I think the ramps on the thrust bearing ground all the way down to almost completely keep the rotating assembly from rotating.

 

 

3. I'd been traveling at highway speeds, more or less keeping a consistent stream of exhaust trying to move the rotating assembly. When I came to a stop though, I'm tempted to say that's when the turbine wheel relieved itself from the shaft. I believe the extreme exhaust gas mass flows provided the torque to twist the turbine wheel right off the shaft. (I'm not 100% sure about this hypothesis though. I only drove about two more miles after I came to that first stop. According to my hypothesis though, that's about the only timespan where the turbine wheel would have to destroy itself and the turbine housing. Could so much damage be done to the housing and shaft in just 2 miles?)

 

 

New plan: take JmP's and everybody else's advice and just swap in a different, normally functioning motor, pull the old one and rebuild it. I found

and I am understanding quickly that this motor needs some TLC.

 

Thank you, thank you to all for your experience and expert advice. I know turbos. In fact, really well. But concerning practical motor rebuilding and specifically the inner workings of an EJ, I am very much a noob. I will be relying on the mountain of knowledge from this and other forums as well as my engineering schooling and experience. I appreciate all assistance and recommendations here.

[Darth SpecB]

Could so much damage happen in 2 miles?

 

My experience says yes because this exact same thing happened to me. And 600 miles after slapping a new turbo on, boom! There went my connecting rod bearings, cam journals, orifices, everything! But hey there are some people who get extremely lucky...

 

Sent from my SM-G950U using Tapatalk

[Max Capacity]

Could so much damage happen in 2 miles?

 

My experience says yes because this exact same thing happened to me. And 600 miles after slapping a new turbo on, boom! There went my connecting rod bearings, cam journals, orifices, everything! But hey there are some people who get extremely lucky...

 

Sent from my SM-G950U using Tapatalk

 

 

True, but the number of those that got lucky is in the single digits. The OP is not one of them.

[MoarBoost]

The OP is not one of them.

 

This is true. I've generally not been a very lucky person

[MilesA]

This is true. I've generally not been a very lucky person

You are like the poster child of the "Please don't try to limp your Legacy GT home" campaign.

 

We should have a sticky post warning people or something.

 

[gkinslow]

They usually only come here after they limp home, unfortunately.

[MoarBoost]

I mean, why do you think I'm here now? haha Idk... people will learn somehow. Either by being proactive and taking preventive measures, or by being ignorant and pushing the envelope and learning how to clean up the mess. Or they don't learn.

 

I just know that if I was this ignorant, then there are a thousand others like me, so I should admit my mistakes, try to document everything I've learned, describe my thought processes and ask for help.

 

For the future, I will be:

-checking oil levels frequently

-changing oil every 3k miles

-sending out oil analyses regularly

-getting AAA

-reading up more on this and other forums

-...

[gkinslow]

Very wise ideas.

 

I learned the hard way too. (many of us did)

 

I should never have bought my car, as it blew the motor less than 2 months after I bought it. I showed up here after instead of before.

 

There is a wealth of knowledge and some good people on this forum. You couldn't be in a better place for your situation.

[MoarBoost]

I've got a few leads on some EJ255's. I'm a little out of touch for what's expected, what is a decent price for a motor?