[Mk2] [Turbo] some progress pics, GT3071R MR2

[djpkins]

can you feel owt through turning the wheel with your fingers...is yours a ball bearing turbo?

[raptor95GTS]

there was a thread on the oc.com and apparently restrictors on oil feeds to turbos isn't neceesary on the 3S and can in fact cause failures..

[djpkins]

As you've gained more power, how much has the oil pressure gone up...idle and full load?

[T.F.S.]

the bearing has a little play in it...not a massive amount

its a ball bearing type..

so it would seem that the restrictor may have been the issue, well either that or a faulty bearing maybe
do you have a link to that thread?

i am afraid i do not have a oil pressure guage at present

[raptor95GTS]

http://mr2oc.com/showthread.php?t=429805&page=1 bit of a read but most things are.

the actual post http://mr2oc.com/showpost.php?p=4792970&postcount=76

If you haven't changed the oil pump the extra power wouldn't change the oil pressure would it? It that not a product of the engine turning, ie more revs = more oil pressure. Whether it's making 200 or 300bhp at 4000rpm oil pressure is the same?

[T.F.S.]

hmmm, having a look through the Garrett website i found this...


Does my turbo require an oil restrictor?
Oil requirements depend on the turbo's bearing system type. Garrett has two types of bearing systems; traditional journal bearing; and ball bearing.

The journal bearing system in a turbo functions very similarly to the rod or crank bearings in an engine. These bearings require enough oil pressure to keep the components separated by a hydrodynamic film. If the oil pressure is too low, the metal components will come in contact causing premature wear and ultimately failure. If the oil pressure is too high, leakage may occur from the turbocharger seals. With that as background, an oil restrictor is generally not needed for a journal-bearing turbocharger except for those applications with oil-pressure-induced seal leakage. Remember to address all other potential causes of leakage first (e.g., inadequate/improper oil drain out of the turbocharger, excessive crankcase pressure, turbocharger past its useful service life, etc.) and use a restrictor as a last resort. Garrett distributors can tell you the recommended range of acceptable oil pressures for your particular turbo. Restrictor size will always depend on how much oil pressure your engine is generating-there is no single restrictor size suited for all engines.

Ball-bearing turbochargers can benefit from the addition of an oil restrictor, as most engines deliver more pressure than a ball bearing turbo requires. The benefit is seen in improved boost response due to less windage of oil in the bearing. In addition, lower oil flow further reduces the risk of oil leakage compared to journal-bearing turbochargers. Oil pressure entering a ball-bearing turbocharger needs to be between 40 psi and 45 psi at the maximum engine operating speed. For many common passenger vehicle engines, this generally translates into a restrictor with a minimum of 0.040" diameter orifice upstream of the oil inlet on the turbocharger center section. Again, it is imperative that the restrictor be sized according to the oil pressure characteristics of the engine to which the turbo is attached. Always verify that the appropriate oil pressure is reaching the turbo.

The use of an oil restrictor can (but not always) help ensure that you have the proper oil flow/pressure entering the turbocharger, as well as extract the maximum performance.





so going by that it would seem that a restrictor would be required...ill be stripping the turbo down tonight to inspect it, i wonder if ill find a blocked restrictor?

i would think not seeing as there is a filter placed just before the turbo so that either leaves the cause being a bad bearing from factory or it is indeed an oil supply issue brought about by the use of a restrictor

[djpkins]

Did you take a look at the oil line mate?

[T.F.S.]

yep, nice and clear...no blockages

[djpkins]

Is the turbo shot though?

[sjm1984]

i would advise you to drop the sump and check for metal filings in the pan and also the oil. pop the rocker cover off to inspect for filings.

A friend of mine had his GT35 from turbo dynamics fail on him and the compressor wheel rubbing putting the metal shavings into the engine and causing engine failure.

Where did you buy the turbo from?

[T.F.S.]

i bought it from GT3 after owens left me waiting for around 3 months with me ringing them every other week to check progress on my order..

every time they told me it was coming in soon and then after 3 months they told me they had never heard of me and had no record of my order lol, true story yo..

the damage to the blade is very minimal (as you can see from the pics), i caught this just as it was beginning to go so i doubt i have contaminated anything to any extent, dropping the oil and doing a compression test is on the cards though bud

the turbo itself died from oil starvation, restrictors are not needed on our engines although you would be led to believe otherwise by reading the advice from garrett which nobody seems to agree with (my bearings are proof that you do not require a restrictor lol)

[djpkins]

Bummer...are you going to throw it back to them, is it under warranty...good man for posting the details though mate.

[T.F.S.]

its been on the car two years..i did try to get in contact with the place that sold it to me but they dont answer or return calls lol

i followed garrets advice on the oil restrictor over 45psi and i would still like to speak with them directly over this but there is no email address on their website..so phone number, no physical address, xxxx me it does not even say what country they are in lol

all technical questions or returns you have to go through your dealer..their advice totally contradicts what is said on the garret site so what do you do?

tell you what, i wont be buying another garret ever again mate..good product, crap aftersales

the turbo is being repaired by a friend...it will be another interesting update to the thread lol.

[jimGTS]

thats not good.

hope it can get sorted soon fella.

[greeny]

I wouldnt be putting too much fault in using the restrictor, as lots of people do and don't have problems. I'd expect not restricting the oil pressure/flow to be more detrimental.

Possible you've just been unlucky chap.

[T.F.S.]

well thats what i thought but i have spoke with the UK dealers and they tell a different story...

[Nails]

What's the uk dealers said? After reading this thread makes me think that I seem to have read more failed turbo threads with garrets than I have with any other turbo. Didn't JJ's have a garrett that did similar?

[T.F.S.]

well they (owens) said not to use them on cars with under 100psi max oil pressure...the only car they fit a restrictor to is some random volvo

i have also read the same info from other dealers...it ranges from 80-100psi but all of them seem to agree that 45psi is way too low

i guess it all comes down to this, in a week or so the turbo will hopefully be back in my hands and ill be removing the restrictor, after that ill know more

[Shmed]

I have a restrictor on mine as I thought they were a must. Can't see why the 3S would be an exception to needing a restrictor, but what do I know.

I'm interested to find out the outcome though. I don't plan on removing my restrictor.

[T.F.S.]

well the turbo core has been stripped down and ill be adding photos soon but first off i have been told that the turbo has an internal 1mm restrictor inside it

if thats not evidence that you dont need to fit an additional external restrictor i dont know what is...

bearings fell apart on disassembly, oil seal showed signs of leaking, burnt oil over turbine heatshield....looks like an 80k turbo