Help settle a question about a turbo/water cooling/compressor surge.

[MongolPup]

So I'm having a bit of a disagreement with someone and would like to solicit some outside opinions. Background:

Motor: 1996 Nissan SR20DET (out of an automatic 1996 Silvia)
Turbo: Garrett BB T-28 (came on the motor, EBC turned OFF, boost 7-10 pounds)

The car left the shop without a blow off valve or coolant lines to the turbo (as well as huge problems with the motor like a dented oil pan/30+ base timing etc). The turbo went bad in a week and a half (roughly). The person I'm talking with says that it is impossible to kill a turbo that quick, and that it was NOT because of the lack of coolant/a blow off valve. This is in 100 degrees + days in Georgia.

The first turbo came off, and another T-28 went on. It has a blow off valve, but still no coolant lines.

Here are my questions to you:

1) How likely do you believe it is because of brutal temps and compressor surge that the first turbo went?
2) How long do you give the second turbo before it goes?

[EmminoDaGreat]

Lack of a BOV will kill a turbo... The coolant lines are not as bad.. but coolant lines do help longevity...

But, if you knew it left like this why would you get on it?
Also, SR turbos are notorious for being weak anyway, it is probably possible it was already wounded and you just finished it off.

[MongolPup]

Motor wasn't wailed on until everything was fixed post first turbo. Except for the coolant lines, because that "hadn't been noticed" yet.

It is my understanding the water cooling is to placate the center cartridge when you turn the car off.

I agree the turbo could have been weak. But the idea that compressor stall and a lack of coolant (and the other stuff) couldn't kill a turbo is absurd.

[green91]

Realistically if its the stock turbo, its 13 years old. Ive personally had one of those t28 go out in a very short period of time that came from an alleged "30-40k" engine. I agree with Emmino that the BOV would make a much bigger difference in the wear than no cooling lines.

[EmminoDaGreat]

Oh I agree that it will kill a turbo, I just cant say how fast.

[MongolPup]

I appreciate your posts gentlemen.

[Z0_o6]

The BOV will certainly keep it alive longer, If it has no coolant I would recommend a turbo timer, or just fix the coolant lines. It shouldn't damage it, however it may impact the life of the turbo SOME. Many turbos are just oil cooled so you should be fine as long as you don't shut it off smoking hot and coke the oil up.

[nx2000det]

http://www.turbobygarrett.com/turbobygarrett/tech_center/turbo_optimization.html

Water cooling is a key design feature for improved durability and we recommend that if your turbo has an allowance for watercooling, hook up the water lines. Water cooling eliminates the destructive occurrence of oil coking by utilizing the Thermal Siphon Effect to reduce the Peak Heat Soak Back Temperature on the turbine side piston after shut-down. In order to get the greatest benefit from your watercooling system, avoid undulations in the water lines to maximize the Thermal Siphon Effect.

[nx2000det]

Without coolant lines, I give it 3 weeks.

[MongolPup]

Thanks again everyone.

Chris - I do have a TT. I just can't help but think that despite Garrett's website (which is a great resource, FYI to anyone reading this who hasn't been there) there has to be SOMETHING good about coolant going through the turbo while it is spinning under load.

My Zilvia replies:


why would you run a 2nd turbo without lines?


a bb turbo without oil/coolant lines will not last very long.


kaboom grrrrrr boom


Coolant lines are for longevity...you need to add them, but it's not going to kill a turbop (BB or not) in a few weeks.

And seeing as it IS a BB turbo, it's less prone to damage form compressor surge...again, not the cause of that first one dying. No BOV isn't that hard on a turbo...but it will cut the life in half, probably...versus running a BOV. Again, it's a longevity issue, not a 'dead in 2 weeks' kinda problem.

My guess: Poor oiling (you said dented pan, right?)

???

- Brian


its not the blow off valve.
your barely boostin shit.
blow offs at that low are for ricers who like the sound of them chirping.

ITS THE COOLANT LINES!!!
how would it not go bad quikly with no cooling system in place??


is he runing an oil restrictor?

[Z0_o6]

Without coolant lines, I give it 3 weeks.

Then why do they still make so many turbos that are only oil cooled? Don't be an idiot, the water cooling helps, absolutely, but it doesn't help to that extent.

[Z0_o6]

Without coolant lines, I give it 3 weeks.

Dammit, double post.

[turbomirage]

This should be very obvious but you need to hook up those coolant lines to your turbo. They do extend the life of your turbo and they are there for a reason. They are there to use, so you would be stupid not to use them, and why not use them is the question? And as far as some turbos only being oil-cooled, it is because they are designed to be only oil-cooled and they do not need to be water-cooled as well. If a turbo is oil-cooled only, it is because the CHRA is designed differently from a turbo that is water-cooled as well, it mainly has to due with what the CHRA cartridge is made of. Most BB Turbonetics turbos are oil-cooled only, because they have a CERAMIC BB center cartridge. Your stock T28 turbo is not this, and was made to run oil-cooled, and water-cooled and I would recommend running both. Unless you want your turbo to have a much shorter life span...

And I do agree with those that say running no BOV will kill a turbo. You would be stupid to not run a BOV when running a turbo, because a BOV serves a very important purpose for a turbocharged engine. It is there to release excess pressure in the intercooler track, so you will not have backpressure. Too much backpressure will kill a turbo, and by not running a BOV you will greatly increase the chances of having too much of it. Too much backpressure will be reversed right back into your turbo, and destroy turbo bearings. Run a BOV as well, in the end it will save you alot of headache and your turbo will love you alot more too.

[Z0_o6]

Unless you have a compressor housing with anti-surge ports, and ball bearings. I have seen some guys run those setups with no BOV to help keep boost up between shifts, but that's neither here nor there.

Jim- LO Fucking L at the Zilvia replies... you nissan guys are some funny fuckers :lmao:

[green91]

Without coolant lines, I give it 3 weeks.


UHH i was going on several years on my EF without coolant lines. So try again.

[nx2000det]

Then why do they still make so many turbos that are only oil cooled? Don't be an idiot, the water cooling helps, absolutely, but it doesn't help to that extent.

how many of those that are just oil, are also BB?

[B18c1Turboed]

I ran the Gt42r turbo and i removed the coolant line. Never had a problem and the turbo still running perfect on another car now.

[Z0_o6]

I ran the Gt42r turbo and i removed the coolant line. Never had a problem and the turbo still running perfect on another car now.

Don't bother trying to tell some people. I hate the guys that want to constantly argue engineering theories instead of real world know-how. They say your shit should blow up in 3 weeks, that shit's gonna blow up in 3 weeks. They got math to prove it.

[nx2000det]

Don't bother trying to tell some people. I hate the guys that want to constantly argue engineering theories instead of real world know-how. They say your shit should blow up in 3 weeks, that shit's gonna blow up in 3 weeks. They got math to prove it.

word....i hate those guys