Turbo Oil Drain Problem, Not Enough Flow?

[Cooper]

I have just got my car back from having some GT2860r-7 turbos installed into my GTR. I received a phone call from my mechanic today saying that there an oil drain problem from the turbos that requires further investigation. They said they measured the amount of oil coming out at 150ml per 15 seconds and they recommend 375ml per 15 seconds. They managed to get the flow up to 200ml per 15 second by drilling out the oil feed from 1.5mm to 1.7mm then to 2.2mm the flow didnt increase from drilling out 1.7mm to 2.2mm.

They say further invesigation is required to find the problem and it could lead to turbo and/or engine faliure and needs to be looked at soon.

I have just spent all my money doing the swap and i cant afford to have the check the problem at the moment. Does anyone have an idea what it might be or if it is a big problem to have.

[R31Nismoid]

Are you using all the stock/factory lines?

If so, there should be absolteuly no issue at all. They are replacement of stock turbos and use the factory lines without issue.

If oil pressure/flow isnt there then i'd look at the lines first, they could have bent them when removing/installing.

And then the oil pump etc after that

[GeeTR]

LoL @ drilling out stock lines for GT2860r-7's.

Crushed or contaminated feed lines is a awesome start... but also a khunt to check at this stage

[The Dan]

LoL @ drilling out stock lines for GT2860r-7's.

Crushed or contaminated feed lines is a awesome start... but also a khunt to check at this stage

+1

you should ask your mechanic if this is his first turbo install or second

[Cooper]

They didnt drill out the oil lines themselves but the oil feed from the block. Thats what i understand from what they have said in my report.

This is exactly what it says they have done on my report:

"Plumb oil drain hoses to containers to check turbo oil drain quantity. A sufficient amount is 375ml/15 sec per turbo. The new turbos are 150ml/15 sec. to raise the amount we loosened the oil feed lines to turbos and removed 'T' piece at engine block. Checked oil feed-hole size was 1.5mm drilled to 1.7mm. Retest flow was 200ml/15 sec. Removed again and drilled to 2.2mm flow. Did not increase from 200ml. This indicates that there is an issue with the oil feed and or pressure which may cause engine and or turbo failure"

[R31Nismoid]

I dont think they've worked on GTR's before if they are drilling lines... thats retarded.

Everyone uses factory lines, untouched.

If you have good oil pressure etc with the motor, nothing is blocking the lines, kinks etc.

It will run as 1000's of cars before yours have

[Cooper]

From what i know they have worked on a fair few GTR's doing turbo swaps etc including getting a modified GTR through regency and 100% legal.

Is it really going to be a big problem? Is it likely my oil pump is giving up? Whats it worth to get an oil pump changed?

Edited May 2, 2008 by Cooper

[rb26s13]

another thing.. from memory the 2860-5's and -7's have built in oil restrictors

[Antimatter]

I have "heard" of people drilling out restrictors for journal bearing turbos.... (no need for -5's etc)

Can be problematic though if too much oil finds its way past the turbine seal....

I say "good on them" for measuring the amount of oil coming out of the oil drains.... who does that? is it in the manual or something?

I dont think they've worked on GTR's before if they are drilling lines... thats retarded.

Everyone uses factory lines, untouched.

If you have good oil pressure etc with the motor, nothing is blocking the lines, kinks etc.

It will run as 1000's of cars before yours have

[Adriano]

I say "good on them" for measuring the amount of oil coming out of the oil drains.... who does that? is it in the manual or something?

I agree, cant have a go at the workshop for being overly cautious, however i wonder if these flow rates are for the stock turbos? Could be the internal restrictors are now doing their thing. PS replacing the oil pump in a gtr isnt a cheap job, kida makes you wonder why nissan didnt design the oil pressure relief valve differently, would make the job hundreds of $$$ cheaper.

[Cooper]

Does anyone know what amount of oil the gt2860r-7 is meant to flow? How much do the restricters slow the oil flow?

Edited May 3, 2008 by Cooper

[The Dan]

Does anyone know what amount of oil the gt2860r-7 is meant to flow? How much do the restricters slow the oil flow?

A Garrett ball bearing turbo (like the one above) requires 1.0-1.5L/min of oil flow at 3bar (44.1psi) engine oil pressure.

At idle you would likely only have approx 25psi oil pressure and at 3krpm around the 40-50psi mark. They need to be testing it at this level.

[The Dan]

AND.....your factory turbos require MORE oil flow than this.