Oddball mitsubishi turbo failure? (Lots of pics)

[forcefed86]

So throughout this engine build (1993 eagle talon) I've noticed a slight amount of non-magnetic goldish dust in my oil filter. Possibly getting a tad worst this last oil change. I figured this could have been alum that picked up the color of the oil since I didn't think I had any brass in the engine. So I scraped up as much of it as possible and dripped some muratic acid on it. I got no reaction. So I figure that pretty much leaves the turbo bearings as the only gold metal in the motor.

Pulled the mitsubishi IHI evo 3 16g turbo today and tore it down. The back face of the thrust washer was pretty tore up and the lower centering bushing for the thrush washer was cracked all down the side. Lucky I caught it in time. The comp. blades had just started to kiss the comp. housing. This seems odd to me. There are no signs of heat build up etc. And the split bushing seems to be what was eating up the thrust washer. Anyone see one of these crack before or know what would cause it?

Strange part is it looked great and had minimal play. I noticed 1 small drop of oil in the intakeof the comp housing when I did this last oil change.

You can tell it just started to touch the comp housing. Blades don't look damaged... Much anyway.

 

[forcefed86]

Back side damage on thrust washer

Cracked bushing

Brass Shaft bushings/bearings looked ok

All cleaned up and ready to go...

 

[dr_frankenstein]

I have seen this type of failure many times with stock turbos.

usually caused by just running high boost. The stock Thrust washer cannot handle the increased loads. particularly if your guilty of not warming your oil in the morning or pushing a stock turbo to its max.

a 360 degree upgrade helps alot, as well as porting and relieving the oiling feeds.

A.j.

 

[forcefed86]

I have seen this type of failure many times with stock turbos.

usually caused by just running high boost. The stock Thrust washer cannot handle the increased loads. particularly if your guilty of not warming your oil in the morning or pushing a stock turbo to its max.

a 360 degree upgrade helps alot, as well as porting and relieving the oiling feeds.

A.j.

Not sure a 360 thrust washer exists for this turbo? That would make sense though. I burried my 30lb gauge quite a bit on the initial spike with this turbo. Boost usually settled at 25psi or so by redline. Wish I would have read your post before reinstalling! Looked like a 50 thou or so hole for the oil supply. I though it looked a tad small. Also this turbo is pressure fed off the intake manifold. The manifold has a pressure regulator that takes oil pressure down to 10-14 at idle and around 25psi at max rpm. I think I'll plumb a line from the filter housing to the turbo feed so at least I get max pressure.

Thank you! :biggrin:

 

[dr_frankenstein]

Not sure a 360 thrust washer exists for this turbo? That would make sense though. I burried my 30lb gauge quite a bit on the initial spike with this turbo. Boost usually settled at 25psi or so by redline. Wish I would have read your post before reinstalling! Looked like a 50 thou or so hole for the oil supply. I though it looked a tad small. Also this turbo is pressure fed off the intake manifold. The manifold has a pressure regulator that takes oil pressure down to 10-14 at idle and around 25psi at max rpm. I think I'll plumb a line from the filter housing to the turbo feed so at least I get max pressure.

Thank you! :biggrin:

agh! your delimma arrives! exactly, there are no 360* for most stockers.

As for the oiling, I usually start real small and work my way up when it comes to messing around with the oil restrictors, but you need to force a bit more oil pressure to that thrust when the boost pressures start hammering them like that.
the problem, is usually the stock non-gapless style of seal ring usually starts seeping real bad when you increase the oiling to the thrust face... its a terrible compromise for the max effort stock turbo.

if your really serious on trying to get all you can from it, I know guys that have rotary knurling done to the thrust to aid in oil retention. but they usually convert to a gapless style seal ring.

Thats why all those "cover Kits" they sell on ebay with the pre-machined covers and wheels for cheap upgrades never last.... they upgrade the wheel to this giant one, start pushing decent boost and watch the thrust fry and crash the wheel into the housing.

A.j.

 

[forcefed86]

agh! your delimma arrives! exactly, there are no 360* for most stockers.

As for the oiling, I usually start real small and work my way up when it comes to messing around with the oil restrictors, but you need to force a bit more oil pressure to that thrust when the boost pressures start hammering them like that.
the problem, is usually the stock non-gapless style of seal ring usually starts seeping real bad when you increase the oiling to the thrust face... its a terrible compromise for the max effort stock turbo.

if your really serious on trying to get all you can from it, I know guys that have rotary knurling done to the thrust to aid in oil retention. but they usually convert to a gapless style seal ring.

Thats why all those "cover Kits" they sell on ebay with the pre-machined covers and wheels for cheap upgrades never last.... they upgrade the wheel to this giant one, start pushing decent boost and watch the thrust fry and crash the wheel into the housing.

A.j.

A wealth of information you are sir!

I try using a bit better oil (VR1 20/50). I was using rotella 10/40. Then getting higher pressure to it to start with. I was thinking about beveling the opening under the thrust washer. That way it would have more of a contact patch without all the added volume?

Probably a crap shoot either way. This 3500lb car trapped 119 at the track with that little 16g screaming(14* wot timing I might add). Hp/weight calc. puts me at over 400hp. Way off the map for this little 16g. With everyone running e85 and tons of boost these days I’m sure we’ll see failures like this a lot more often!

 

[dr_frankenstein]

A wealth of information you are sir!

I try using a bit better oil (VR1 20/50). I was using rotella 10/40. Then getting higher pressure to it to start with. I was thinking about beveling the opening under the thrust washer. That way it would have more of a contact patch without all the added volume?

I dont think changing weight will make that much of a difference in the stocker. the orifice is only gonna pass what its designed to pass - i would fear reduced oil flow with the heavier weight. The beveling will help, but I dont see it being a cure all, there probably will be thrust issues at higher than stock boost. And remember when you grind or sand the cartridge it has to be clean clean clean after.

Probably a crap shoot either way. This 3500lb car trapped 119 at the track with that little 16g screaming(14* wot timing I might add). Hp/weight calc. puts me at over 400hp. Way off the map for this little 16g. With everyone running e85 and tons of boost these days I’m sure we’ll see failures like this a lot more often!

exactly, your just really running the snot out of that little bugger. but those are some fantastic numbers for a stock system.

I mean, these mods have helped me with stockers,I wouldnt say that they replace a much better aftermarket unit - because a nice new precision unit would rock socks..... but they can help you get by - or in a 100% stock class - the slight edge.

A.j.

 

[forcefed86]

I dont think changing weight will make that much of a difference in the stocker. the orifice is only gonna pass what its designed to pass - i would fear reduced oil flow with the heavier weight. The beveling will help, but I dont see it being a cure all, there probably will be thrust issues at higher than stock boost. And remember when you grind or sand the cartridge it has to be clean clean clean after.



exactly, your just really running the snot out of that little bugger. but those are some fantastic numbers for a stock system.

I mean, these mods have helped me with stockers,I wouldnt say that they replace a much better aftermarket unit - because a nice new precision unit would rock socks..... but they can help you get by - or in a 100% stock class - the slight edge.

A.j.

That post was a bit misleading. If they had a 40w vr1 I could buy local I would run that. I was just switching to a better oil with more zinc/phos etc. Thanks for all the info I'll post back if I grenade this one. :biggrin:

I've got the PT-68. on the GN/rx-7 hybrid toy. Thats a different animal!