GOLFMK8
GOLFMK7
GOLFMK6
GOLFMKV

Quebster's Built/Ported 2015 GTI S 6MT - The Good, the Bad, and the End

Gvazquez

Go Kart Newbie
Location
North Carolina
I also think that this is the main contribution to turbo failures on this platform because a pressurized crankcase also means that your turbo drain line isnt actually draining properly because it's a gravity drain line that goes to the block. If theres pressure there, then you wont have sufficient drainage for the turbo. Just speculation of course but tell me what you guys think.
 

JerseyDrew77

Autocross Champion
Location
Virginia & NC
Well, what are some warning signs that the crankcase is not pressurizing correctly? There's got to be a way to prevent it from getting catastrophic.
 

Gvazquez

Go Kart Newbie
Location
North Carolina
I would imagine random seals will start leaking some oil.
 

Gvazquez

Go Kart Newbie
Location
North Carolina
What do you mean by weep?
 

Gvazquez

Go Kart Newbie
Location
North Carolina
Lol. I mean that is common and even after rebuild on mine with all new gaskets, I suspect this is an actual problem versus a normalized thing for these engines.
 

JerseyDrew77

Autocross Champion
Location
Virginia & NC
There's some oil weep all around the cam girdle, back by the VVT actuators, at the 2 cam actuators, oil cap always has sweat on it, etc... She sweat, wet, got it goin like a turbo Vette.
Full send it! Make that bitch cry!!!
 

The Dude

Go Kart Champion
Location
PNW
a properly plumbed PCV system should pull a slight vacuum on the crank case, shouldn't it? I'm gonna have to read more about how the system is supposed to work, because my understanding from school is that you keep a slight vacuum on the crank case so that you don't pressurize it and blow gaskets and seals out.
 

Gvazquez

Go Kart Newbie
Location
North Carolina
a properly plumbed PCV system should pull a slight vacuum on the crank case, shouldn't it? I'm gonna have to read more about how the system is supposed to work, because my understanding from school is that you keep a slight vacuum on the crank case so that you don't pressurize it and blow gaskets and seals out.
It should at idle and then go closer to 0 with vacuum not applied, i.e under load/acceleration.
 

Quebster

Drag Racing Champion
Location
Dallas, Tx
I think that blowby does and at the same time doesn't make sense. lol. I think if it's blowby, I wouldn't call it excessive, but would call the ventilation inadequate. Why some have the issue and some don't, hard to say. We all know how finicky these motors seem to be. Maybe it's something with my early '14 build. But I don't think <10% leakdown @ 100psi warrants "excessive" blowby in any scenario.

Regardless... nail in the coffin here. I was out doing some logs yesterday and had a turbine blade just break right off. No idea why. I'll scope my cylinders and see if I have pieces of my pistons missing or anything, but one blade breaking and the rest being fine doesn't seem like FOD to me.

IMG_0897 (Edited).jpg


I was struggling to convince myself to give up on the GTI but this seals the deal for me. I've been telling myself if I had to pull the turbo back off, the stock IS20 is going on and I'm not taking it off. So here we are! GG gents
 

Diggs24

Autocross Champion
Location
de plains! de plains!
Car(s)
2015 GTI; 2003 Saab
One other item. A compression test is done at TDC, yes? The assumption is that the bore is consistent all the way down in that case, no? What if it isn't? Could that not be the cause of the blowby? Just spitballing here.
 

Diggs24

Autocross Champion
Location
de plains! de plains!
Car(s)
2015 GTI; 2003 Saab
Also, sorry to keep posting but did that wheel need that much grinding to balance? It's out of focus but damn it's missing a healthy chunk at the bottom...
 

Quebster

Drag Racing Champion
Location
Dallas, Tx
One other item. A compression test is done at TDC, yes? The assumption is that the bore is consistent all the way down in that case, no? What if it isn't? Could that not be the cause of the blowby? Just spitballing here.
Not sure.
Also, sorry to keep posting but did that wheel need that much grinding to balance? It's out of focus but damn it's missing a healthy chunk at the bottom...
You're talking about the "nut" in the center? That's just how it is, it isn't ground I don't believe. Or is it? I guess I really don't know. I just assumed that was the shape of the nut. lol

Here was my V2 when it was new:
IMG_1369.JPG
 
Top