Why Did My Turbo Blow!?

[salad]

Hi, I'm just wondering how much oil flow the standard RB20 supplies to its turbo? I have been told that the turbos need 1.5L/min, but the guy has said a couple of other things to make me think twice about it.

Any help would be appreciated

EDIT

OK, I've gotten onto GCG another way and found out that the GCG highflows need around 900cc/min to survive, which is exactly what was measured out of the oil feed line. So now I have to figure out why it's been starved of oil...

MTQ suggested that somehow something may have been stuck in the line, but then somehow, relieved itself, this seems a bit odd though.

The only other thing I can think of is the car stalled a couple of times on track, but I started it again straight after. Someone mentioned coking before as the bearings/shafts/races were all black instead of blue. I was always under the impression though that only plain bearing turbo suffered such huge problems from the car stallin unexpectedly or something.

Any help would be great

Cheers

Edited July 9, 2007 by salad

[R31Nismoid]

Think twice in relation to what?

[salad]

Whether or not it should be 1.5L/min or infact less.

On my car to achieve this figure we had to drill out both restrictors in the oil feed banjo bolts. With the restrictors before it was only getting around 0.9L/min.

I'm just after confirmation of what he has said. Or if it's not right, I have to have a couple of words with him.

[R31Nismoid]

So your running a stock setup? Stock turbo etc? Or an aftermarket one?

[salad]

Back to a stock RB25 turbo now, was running an RB25 GCG highflow, which seized up after 2 days of running (1 day on a dyno and then 4 laps of Mallala). The same guy was the last to have it apart to do the rear seal on it, just want to make sure he's not trying to get out of it or anything like that...

[R31Nismoid]

You would soon tell by looking at the turbo bearings if the failure was oil related or not.

If they have blue scores on them and so on, thats lack of oil.

Has he shown you pics or have you seen the bearings? So you can confirm the story?

Whats the oil pump like? Or maybe you have some blockage.

Turbos generally die for a good reason. Maybe your unlucky and it was a bodge cartridge but its unlikely.

Was there enough oil in the sump? (silly i know, but 1ltr overfill makes a big difference).

Im not sure on what flow is required, but everything around it should match up

[salad]

Well I've got the whole turbo at home with me now, all in pieces. There is no blue on the bearings, they're all black and there is some brown on the shaft too. All the balls of the bearing have turned black too, along with the races that look like they have melted a bit...

No idea about the oil pump, but he did suggest that that may be a problem as the restrictors needed to be drilled out to get what he said was the required oil flow.

There was plenty of oil in the sump, not overfull, but full.

[BHDave]

Was it a fresh rebuild when it went on your car? What oil was the previous owner running through it and was he shutting it down hot? Sounds a lot like coking to me.

[salad]

Was a 2nd hand turbo, but then took it to the guy to get the rear seal done and he said there seemed like there would be a good 2-3years left in it.

2 days later...

No idea of turbo's previous history though...

Also thought I'd mention, the bearings actually fell apart, the shaft bent and the wheels hit the housings.

[1400r]

doubt it was even looked at when you first took it in

get a second opinion on why it failed

was it checked to make sure it was really rebuilt?

[salad]

Yeah, I'm gonna give MTQ a ring tomorrow. He didn't rebuild it, just put a rear seal in, we'll see what they say tomorrow anyway.

[Cubes]

Good luck Salad.

Also interesting to note the std rb25 turbo hasn't had any issues previously or after.

[salad]

Yeah, 2 years of track work with RB25 turbos and not a single oil problem

MTQ didn't know how much oil they should be getting, but showed them the turbo and they said oil starvation too. Actually started wearing through the shaft, taken about 1mm out of the radius...

Then I thought, hey GCG make the highflow, they should know how much oil they require to run, but no one there knew the required flow rate either, just said designed to run off standard oil pressure.

So now I know that it's oil starvation that has caused the turbo to die, but I have no idea what has caused the oil starvation.

Anyone else have any thoughts? Would like to get all of this sorted before I put another good turbo on and potentially have a repeat...

[Beer Baron]

at what RPM are they measuring this 1.9l/m?

it seems awfully coincidental that someone touched your turbo (inspected, replaced seals whatever) then 2 days later it failed. I know where I'd be looking.

[Simon-S14]

as do i.... i told ya showza, this guy is taking the easy option out by saying oil starvation and then washing his hands of it... however i HIGHLY doubt that you have an oil related problem as you were running the 25 turbo for ages with no dramas, along weith the current 25 turbo with no drama;.. so i think that the rebuild itself is of questionable quality...

[Simon-S14]

as do i.... i told ya showza, this guy is taking the easy option out by saying oil starvation and then washing his hands of it... however i HIGHLY doubt that you have an oil related problem as you were running the 25 turbo for ages with no dramas, along weith the current 25 turbo with no drama;.. so i think that the rebuild itself is of questionable quality...

[Cubes]

You blokes with the GTST std sump.

Do you do the 1ltr overfill for trackwork also?

[Simon-S14]

ive never ever ever had an oil control issue, fill to stock levels and had several turbos on rb20's over the years an dhave done more laps on a track then most here... showza will vouch for that.

I really believe that oil controll issues are limited to the RB26 only... the 20 takes a real beating on the track thats for sure!

[Cubes]

I'm assuming you've ran on semi's?

I think it has a lot to do with the oil pump; mine with basically a rb20 head on steroids (r32 rb25de) with a good pump dumps shit loads of oil in the head over 6000rpm. Enough if I don't run a catch can for it to plume the rear vision full of smoke.

Fingers crossed thats all sorted. All though a little worried about doing so I've taken Sydneykids suggestion of blocking off the rear oil feed and running a single 1.5mm up front. The reason I'm a tad worried is I haven't heard any one say YES its fine with the RB20 to do this and those with R33 RB25's that have done it with no issues have an extra head oil feed via the VCT. Time will tell. :S

I might see you out there some time soon Simon/Salad.

[Simon-S14]

nah i havent ran semi's ate a grip event but my car has been used for drift, big arse scando flicks are 200 kph on back straight of mallala do generate a fair wack of G forces also... gets the oil flowing and since this is mostly on the limiter you would expect a fair wack of oil flowing... However i have never had a catch can on my rb20, and not had any probs.

got a 25 now, and plan on doing some grip times with slicks so we'll see how the oil probs go...