[supercati]

Hello everyone,

I've just done a wastegate rebuild on my 335xi, and after the first startup during the installation I noticed my front turbo is leaking oil just in the middle, where there is the VBand (CHRA if I am not wrong).

I cleaned everything with brake cleaner, checked again, and its for sure leaking from there. If the car is at idle, it doesn't leak at all (or almost nothing), but as soon as you rev it a little bit it leaks from there...

Before turbos dissasemble it was NOT leaking from there (or anywhere on the turbos). All gaskets on the turbo lines where changed.

What could I check?

Here are a couple of pics.






Update: #17

Update: #21



UPDATE: After the turbo rebuild (CHRA replacement)... everything works as expected now, zero oil leaks!

When doing the job I noticed that the turbine and the compressor were not correct aligned... that was probably the problem.

Thanks to everyone involved.

[fredcase]

Don’t look good. Make sure it’s not leaking elsewhere, and running down onto the front turbo. Ofhg or vcg.

Make sure the oil feed from the top is not leaking. It could be not draining well, and getting past the seal.

[supercati]

Originally Posted by fredcase

Don’t look good. Make sure it’s not leaking elsewhere, and running down onto the front turbo. Ofhg or vcg.

Make sure the oil feed from the top is not leaking. It could be not draining well, and getting past the seal.

It's leaking from the CHRA, I am 90% sure; OFHG was replaced while doing turbos WG and doesn't leak now.

About the top oil feed, if it were leaking, it would leak from the other side (I mean not on the V Band)... Isn't that right? According to the design it has:





I can't understand why it started leaking now?? I have seen several posts with the same issue, but no one posted the cause/issue/solution. Same as me: after WG rebuild, turbos leaking from the CHRA.

[fredcase]

Could be a million reasons why. I think most people don't bother rebuilding just the wsastegates for this very reason. While they are out, might as well total rebuild.

I would begin to suspect, the drain wasn't 100% perfect on re-intall.

Old turbos didn't like the re-install start up. Unless you primed them properly.

I had an identical issue, but, luckily mine was a rear turbo.

If you are having excessive oil consumption, pull the downpipes, check axial shaft play.

[supercati]

Originally Posted by fredcase

Could be a million reasons why. I think most people don't bother rebuilding just the wsastegates for this very reason. While they are out, might as well total rebuild.

I would begin to suspect, the drain wasn't 100% perfect on re-intall.

Old turbos didn't like the re-install start up. Unless you primed them properly.

I had an identical issue, but, luckily mine was a rear turbo.

If you are having excessive oil consumption, pull the downpipes, check axial shaft play.

I primed the turbos before first start up (disconnect injectors, crank for 10s (x2)).

The car is still on axle stands and without subframe, I just noticed this after first start up... I don't know what else to check, I read also about PCV issues.

I will remove downpipes and check the shaft again, but as said, I can't understand the turbo wasn't leaking before WG rebuild, that's why I just did WGs.

[fredcase]

Originally Posted by supercati

I primed the turbos before first start up (disconnect injectors, crank for 10s (x2)).

The car is still on axle stands and without subframe, I just noticed this after first start up... I don't know what else to check, I read also about PCV issues.

I will remove downpipes and check the shaft again, but as said, I can't understand the turbo wasn't leaking before WG rebuild, that's why I just did WGs.

Whew, if the car is still up, and subframe is off, pulling the downpipes is easy. You might be worrying about something minor. It may be worth having the turbos inspected by someone local .

[supercati]

Originally Posted by fredcase

Whew, if the car is still up, and subframe is off, pulling the downpipes is easy. You might be worrying about something minor. It may be worth having the turbos inspected by someone local .

Yes, now it's "easy" to perform checks.

I will remove DPs and have a look at the front turbo, and will post here again

[Jeef]

I would have just put new turbos. doing all this work and not putting new parts in?

[fredcase]

Originally Posted by Jeef

I would have just put new turbos. doing all this work and not putting new parts in?

CAPTAIN HINDSIGHT! Great input bud.

[Jeef]

Originally Posted by fredcase

CAPTAIN HINDSIGHT! Great input bud.

just doesn't make sense

[supercati]

Originally Posted by Jeef

I would have just put new turbos. doing all this work and not putting new parts in?

Because turbos were OK before, just wastegate rattle and 30FF, and I thought that there was no need to do more there.

If I want to rebuild the turbo that is leaking... What should I buy? New CHRA? Is this kit also necessary?

[Jeef]

whats the mileage on them

[fredcase]

Originally Posted by supercati

Because turbos were OK before, just wastegate rattle and 30FF, and I thought that there was no need to do more there.

If I want to rebuild the turbo that is leaking... What should I buy? New CHRA? Is this kit also necessary?

I wouldn’t use that kit. Turbolab is just re-selling Chinese junk. Reach out to Rob at RB turbos, I think he sells quality chra’s at a reasonable price.

I gotta ask now, what wastegate rebuild kit did you use?

[Foghorn]

I would think the oil supply line is the culprit if you’re positive the chra are not leaking. The oil supply line flange is immediately adjacent the v band clamp on top of the chra, if you have a leak there it’s easy for oil to drip on the clamp.

[fredcase]

Originally Posted by Foghorn

I would think the oil supply line is the culprit if you’re positive the chra are not leaking. The oil supply line flange is immediately adjacent the v band clamp on top of the chra, if you have a leak there it’s easy for oil to drip on the clamp.

Like I said above, that would be the first thing I check. Maybe the o-ring on the feed got pintched. Easy check, easy fix. Best case scenario.

[supercati]

Originally Posted by Jeef

whats the mileage on them

130.000km / 80.000 miles

Originally Posted by fredcase

I wouldn’t use that kit. Turbolab is just re-selling Chinese junk. Reach out to Rob at RB turbos, I think he sells quality chra’s at a reasonable price.

I gotta ask now, what wastegate rebuild kit did you use?

I used Turbolab wastegate kit...

Originally Posted by Foghorn

I would think the oil supply line is the culprit if you’re positive the chra are not leaking. The oil supply line flange is immediately adjacent the v band clamp on top of the chra, if you have a leak there it’s easy for oil to drip on the clamp.

Originally Posted by fredcase

Like I said above, that would be the first thing I check. Maybe the o-ring on the feed got pintched. Easy check, easy fix. Best case scenario.

You both are right, yes. That's the first thing I will check once I pull the turbo out again (in about 10/15 days). Hopefully it's this but I am not very positive about that scenario...

[supercati]

Update: Front turbo with downpipes removed... Zero oil, and and no play in the shaft. Can't understandt what's going on honestly.
I also removed water pump, thermostat etc to gain accés from top and can't see oil leak on top of the turbo.



I will continue until front turbo is out.

[IllSic_Design]

hmm hard to say over the internet. You're gonna need to clean it off and try to find the source of the leak as soon as it starts leaking again

[blaster3500]

Originally Posted by supercati

Update: Front turbo with downpipes removed... Zero oil, and and no play in the shaft. Can't understandt what's going on honestly.
I also removed water pump, thermostat etc to gain accés from top and can't see oil leak on top of the turbo.



I will continue until front turbo is out.

If you still have the downpipe off get a bright light and try to look at the heat shield behind the turbine wheel. See if it looks wet at all.

[IllSic_Design]

Originally Posted by blaster3500

If you still have the downpipe off get a bright light and try to look at the heat shield behind the turbine wheel. See if it looks wet at all.

If the center cartridge was leaking as bad as it was thought in the first post then he would almost for sure have oil showing on the hot side of the turbo right there, not just behind the turbine

[supercati]

Update: turbo out. There is not play on the shaft as said, no oil as well on the inside. Top and bottom oil lines had their o-rings and where ok (I replaced them).

I will order a new CHRA and replace it. It's the only thing that can be wrong inside, or a seal etc... what do you think about it?

There is some oil on the exterior that fall when I disconnected the top oil line on the photos.

[fredcase]

Check Axial play and radial play.

Any oil leaking from other places onto the turbo?

Ofhg or vcc?