Turbo Bearings

[paulr33]

Hi,

As most of us know (well at I least I think we do) most OEM turbochargers are ball bearing.

There are some aftermarket brands that are also ball bearing (hks, garrett) and some that are plain or journal bearing (trust, kkk) and so on. I am curious as to how people using Trust and KKK are avoiding the plain or journal bearing failures that are outlined in one of our recent discussions ->

http://www.skylinesaustralia.com/forums/in...5981&st=260

The reason I ask this as we were discussing this and it obvious the stock evo turbo is a mitsubishi unit, which I would expect would be the same as a trust unit. That is plain bearing oil cooled only.

Is this correct? or a wrong assumption?

Do Mitsubishi make ball bearing units?

Are the trust t517z's t518z's for twins in GTRs ball bearing or plain/journal?

Are the bigger variants larger td05's td06's ball, plain or journal?

If they are plain/journal how do they avoid bearing failure when instant power off.

Surely the evo stocker turbo doesn't fail when you turn the car off instantly if its mega hot?

Are there any OEM units that are plain/journal bearing? How do they avoid failure with "instant-off" scenario's ?

[silver gts-t]

mitsu turbo's are supplied to trust but i dont think trust releases and specs on their turbo's so i pressume the only changes they make are to the housings, evo turbos are different varients of the TD05 and the only larger varients to the td06 is the td07 and then after that trust makes the t67 and etc

http://www.zerotohundred.com/newforums/showthread.php?t=655

[Warpspeed]

You say the turbo is oil cooled, then it most certainly is an older sleeve bearing unit.

I have never seen a ball bearing turbo that was not water cooled. The reason being that ball bearing turbos require far less oil flow, and the reduced oil flow just cannot pull out enough heat all by itself.

[mad082]

i'm pretty sure that the ca18 and sr20 turbos are plain bearing.

EDIT: just checked it, and yes, s13 sr20det have journel bearing turbos. s14 went to ball bearing.

Edited August 9, 2006 by mad082

[BHDave]

s14 and 15 adm are also plain bearing, the s14 and 15 jdm got bb. Don't ask me to start quoting different cart numbers, it's been done to death on silvia forums and people still don't accept it.

[paulr33]

right so why is it that a particular hiflow with plain bearing is more prone to bearing failure vs an oem plain bearing unit ? i dont get it? is there something im missing

[mad082]

i just got my info off the sr20 forums, but i wasn't reading that closely. just saw s13 and s14 at the front. didn't read fine print into what model. but i know that the s13 were journel, cause my sr20 powered 180sx was.

i know plenty of them that have had straight turn offs after thrashing them and they never seized. it would have to be a serious thrashing, and pretty crap oil flow for them to seize. generally the oil will flow around for a short amount of time after turn off till it cools slightly.

[BHDave]

right so why is it that a particular hiflow with plain bearing is more prone to bearing failure vs an oem plain bearing unit ? i dont get it? is there something im missing

I'd say it's an assumption....

Do you know if said highflow has water cooling? Because i'm fairly certain even the plain bearing EVO TD's have watercooling, unlike the aftermarket trust units, and all the oem garretts i've seen on cars have water cooling, though my aftermarket one doesn't.

it hasn't seized on me yet btw

[Tangles]

Its the buildup of crud in the oil lines that leads to turbo failure (ie lack of oil flow)IMO

[mad082]

Its the buildup of crud in the oil lines that leads to turbo failure (ie lack of oil flow)IMO

cause by people not servicing often enough, or using the wrong oil. if you used 5w50 you would run more chance of seizing it than if you ran 5w30, as 5w30 is a thinner oil. and 5w50 has more chance of breaking down due to the higher content of polymers.

Edited August 9, 2006 by mad082

[Cubes]

Its the buildup of crud in the oil lines that leads to turbo failure (ie lack of oil flow)IMO

Hot shutdowns cause the oil to coke.

Do this enough the lines/turbo will eventually coke up and oil flow will be restricted; its quite possible the BB turbo's get away with this a tad longer as they don't require as much oil.

[Slide]

Hi,

As most of us know (well at I least I think we do) most OEM turbochargers are ball bearing.

There are some aftermarket brands that are also ball bearing (hks, garrett) and some that are plain or journal bearing (trust, kkk) and so on. I am curious as to how people using Trust and KKK are avoiding the plain or journal bearing failures that are outlined in one of our recent discussions ->

http://www.skylinesaustralia.com/forums/in...5981&st=260

The reason I ask this as we were discussing this and it obvious the stock evo turbo is a mitsubishi unit, which I would expect would be the same as a trust unit. That is plain bearing oil cooled only.

Is this correct? or a wrong assumption?

Do Mitsubishi make ball bearing units?

Are the trust t517z's t518z's for twins in GTRs ball bearing or plain/journal?

Are the bigger variants larger td05's td06's ball, plain or journal?

If they are plain/journal how do they avoid bearing failure when instant power off.

Surely the evo stocker turbo doesn't fail when you turn the car off instantly if its mega hot?

Are there any OEM units that are plain/journal bearing? How do they avoid failure with "instant-off" scenario's ?

t517z's t518z's are journal bearing and they also sell them in ball.

Nearly the entire TDO range has been released journal bearing.

Turbonetics - Journal bearing

Turbonetics also use single journal and single ball in unison to cope with the weight of heavy shafts/turbines for cars making 800hp + using big singles.

Garrett also still sell nearly thier entire range in journal bearing also.

There is no difference in bearing design between trust and Garrett,

We recondition Truck turbo's

The entire Nissan UD truck series run journal bearing Garrett turbo's with no difference in journal bearing design to any other.

Not to mention nearly every other Line Haul/Detroit tuck using only journal bearing turbo's

CATERPILLAR tractors, farm machinery mainly use Schwitzer turbo's which are all journal bearing.

Holset, kkk, CUMMINGS, KOMATSU, Ragay, biagio Toyota released the ct9 ct20 ct26, hitathi ht80, kawasaki, IHI, caterpillar themselves, MTU turbosystems all use journal bearing.

Its not a fact that hot shut offs kill journal bearing as you can see there would be hundreds of thousands to even millions of cars/trucks/boats/machinery not to mention Quary machinery which all use journal bearing turbo's on trucks as large as a house would be in repair after every shift.

There are always other cotributing factors to turbo failure and for as many journal bearing failures there ARE as many ball bearing failures if the ratio of journal to ball bearing turbo's as taken into account.

As there are far more journal bearing turbo's released and sold still today than ball bearing.

We have never had a failure because of hot shut down.

We still also have not had a turbo returned to us yet due to anything journal bearing related.

right so why is it that a particular hiflow with plain bearing is more prone to bearing failure vs an oem plain bearing unit ? i dont get it? is there something im missing

hearsay?

[Cubes]

Agree'd really it is speculation.

[paulr33]

ok thanks. im not disagreeing or agreeing. i was just curious on the matter of the subject. i recall it was a heavily debated topic, and i remember there was no real final "this is why" answer.

[Cubes]

I believe the std GTR turbo's are also journal.

[Kinks]

right so why is it that a particular hiflow with plain bearing is more prone to bearing failure vs an oem plain bearing unit ? i dont get it? is there something im missing

Plain bearing turbos have a thrust washer/plate (been a while since I researched it, can't remember). In short, OEM turbos have a partial disc (ie the thrust bearing goes 2/3 of the way around the turbo shaft). Aftermarket bearings go all the way around, this provides more resilience when power levels are raised.

This is why when you simply 'highflow' a turbo for more power but don't replace the bearing, you run a higher risk of failure.

[RB30-POWER]

When the vehicle is turned off the water thermosyphons around the engine and through the turbo and it removes the heat anyway, one of the primary reasons they are watercooled.

If the vehicle has a oil cooled only turbo you have to let it idle down for a short period if your been thrashing otherwise the oil can coke easily, especially minerals, not such a problem with good synthetics these days.

As for plain bearing turbo's being unreliable, i don't really agree with that at all, if thats whats being said, plain bearing turbo's have been used for decades without trouble.

Yes ballbearing turbo's now offer advantages over the older style though.

Sorry, but what was the topic again?, is it that you are saying the new evo's have a oil cooled only turbo? sounds hard to believe?

[Slide]

Plain bearing turbos have a thrust washer/plate (been a while since I researched it, can't remember). In short, OEM turbos have a partial disc (ie the thrust bearing goes 2/3 of the way around the turbo shaft). Aftermarket bearings go all the way around, this provides more resilience when power levels are raised.

This is why when you simply 'highflow' a turbo for more power but don't replace the bearing, you run a higher risk of failure.

You would be refering to a 270 degree thrust or less and a 360 degree thrust.

I have never heard of any place that highflows turbo's that didnt replace every single part except for the housings and cartridge core with new.

The Garrett overhaul kits include everything and anybody that highflows turbo's should or does use these kits.

The only thing remaining to get to complete the highflow is the Shaft/Turbine and compresor wheel.

The rest is in machining and balancing.

[Munna1]

Very interesting, by the sounds of it the only real advantage of a ball bearing turbo is responce.

Edited August 10, 2006 by Munna1

[R31Nismoid]

Aaron, nice examples there.

But you forget a key thing, are they high shaft/heat applications?

And do all of the trucks, machinery have thier operators just "turn it off" when thier done?

Go to a servo near a solid hill or similar, watch a truck pull in.

See if he turns it off right away