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Tons of smoke after rebuild


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Building the engine was a lot of fun, but boy is this break in stuff nerve wracking. After priming the oil pump and reinstalling the fuel pump fuse the engine started right up. Then it dumped the oil out of an open bolt hole in the back of the head. This was caught immediately and the engine was shut down. Installed the bolt, topped off the oil, and tried again. It ran okay for about 30 seconds before my extra set of eyes saw the smoke at the exhaust. Lots of it. I assume some smoke might be normal with assembly lube still in some areas, but this was clouding up the driveway. Spoke with a mechanic friend who mentioned it may be a result of the rings not being seated yet, but 10-20 minute drive of light acceleration(base map tune, so no boost), jumping off the gas to allow for vacuum, has not seemed to change anything. Vacuum is reading around 11 lbs when I let off. The boost got slightly over zero near the end of the drive and threw a p0014 code almost immidiately as I crossed into boost, and the af shot up to 19

 

I’m not sure if this needs more attempts at seating or more checking around under the hood. The car smokes at idle, when first getting on the gas, then clears up slightly, then completely goes away at full vacuum. Any thoughts?

 

Engine sounds like all is well

A/f is holding around 14-14.7(as long as it see no boost)

Oil pressure light stays off

No knock detected

 

I’ll be calling the tuner who also builds a lot of performance subaru engines when they reopen Tuesday, but wanted to see if anyone has any thoughts on an easy fix.

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yeah mine definitely didn't really smoke at all after I rebuilt it.

 

Double check that you have the correct oil feed line banjo bolt. You could be dumping oil in through the turbo.

You could also have your PCV lines incorrectly run and are sucking oil into the crankcase.

 

Those are the first places I'd check.

 

Edit:

 

Also check that your turbo oil return line isn't pinched it could be pooling up in there.

Edited by Aphex28
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So the turbo is soaked inside with oil (bad seal) our outside with oil (due to lines)? If it's the inside as you said above, that probably explains the smoke, right? turbo isn't getting hot since you aren't getting into boost, so smoke is minimal?
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Turbo is soaked inside. It doesn’t smoke for a little until the car warms up a bit. My thought is that the oil is getting inside the exhaust after the manifold. There should be constant smoke from startup on if the oil was burning in the cylinders, but being that the turbo gets hot from exhaust gasses alone, I think I’m looking at the turbo as the issue. Whether it’s the seals or the pcv/oil lines is my next investigation. If I end up stumped in that investigation, I have another stock vf54 to test with.
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I think I’m looking at the turbo as the issue. Whether it’s the seals or the pcv/oil lines is my next investigation.

 

I would guess it is the BNR turbo seal. You are on the right track and that is how I would proceed. I would just make the lines don't crossed up and your sucking air from valve cover into the intake tube before the turbo.

 

Also does the BNR turbo need an oil restrictor (or a different one)? I had an issue on my GMC Syclone's aftermarket ball bearing turbo where I had a little too much oil pressure and it would leak past the oil seal. If I let it idle, it would smoke out the exhaust and the wastegate shaft would get wet with oil. I put in a restriction and went away.

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I would guess it is the BNR turbo seal. You are on the right track and that is how I would proceed. I would just make the lines don't crossed up and your sucking air from valve cover into the intake tube before the turbo.

 

Also does the BNR turbo need an oil restrictor (or a different one)? I had an issue on my GMC Syclone's aftermarket ball bearing turbo where I had a little too much oil pressure and it would leak past the oil seal. If I let it idle, it would smoke out the exhaust and the wastegate shaft would get wet with oil. I put in a restriction and went away.

 

yeah, I'm with him. Like I was wondering, especially since you're running that 18g (which I didn't realize before) it could be using a different oil feed specification. What you're describing is like when we were running the wrong oil feed restrictor on a GT3076 that we built.

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Just out of curiosity, does anyone know if the scavenger pump is feeding oil to the turbo or pulling oil from the turbo? Based off the name I’d assume it pulls oil back into the head from the turbo.

 

It should be pulling from the turbo oil pain. I would make the turbo to scavenge connections are all secure, I would imagine if it has an air leak it would not be able to pull oil from the turbo oil pan, which could cause your issue if the turbo was flooded with oil. Also make sure the scavenge pump banjo bolt does not have a filter in it (incase you got them mixed up with the AVCS banjo bolts)

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So I did check the restrictive banjo bolt that goes in the turbo and it seems almost impossible to have the wrong bolt in place there. The bolt is actually a smaller thread size than anywhere else, and all other bolts would not have fit in that oil line. As for the banjo bolts in the scavenger pump. The bolt in the top of the scavenger pump has a dimple in the head of the bolt and a restrictive hole similar to the one on the turbo, and the one that goes in the back has a larger hole similar to the turbo coolant pipe banjo bolts with no filter.

 

Routing of the pcv lines seem okay from what I can see without pulling the intake. The lower line of the turbo oil pan runs to a hard pipe connected to the scavenger pump while the upper joins to the correct line of a pair of hard pipes.

 

:confused:

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I think that bolt in the top of the scavenger pump is my issue. Can someone please confirm that bolt should have a good size hole in the side (maybe quarter inch) and not a pinhole. This would cause the the scavenger pump to struggle to pull out oil. Please be this.
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So I did check the restrictive banjo bolt that goes in the turbo and it seems almost impossible to have the wrong bolt in place there. The bolt is actually a smaller thread size than anywhere else, and all other bolts would not have fit in that oil line. As for the banjo bolts in the scavenger pump. The bolt in the top of the scavenger pump has a dimple in the head of the bolt and a restrictive hole similar to the one on the turbo, and the one that goes in the back has a larger hole similar to the turbo coolant pipe banjo bolts with no filter.

 

Routing of the pcv lines seem okay from what I can see without pulling the intake. The lower line of the turbo oil pan runs to a hard pipe connected to the scavenger pump while the upper joins to the correct line of a pair of hard pipes.

 

:confused:

 

 

48f5e8321fb0ddb4e23b14e728525ef6.jpg

Photo is highlighted of the hose to drain the turbo oil pan.

 

 

Sent from my iPhone using Tapatalk

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48f5e8321fb0ddb4e23b14e728525ef6.jpg

Photo is highlighted of the hose to drain the turbo oil pan.

 

 

Sent from my iPhone using Tapatalk

 

Got it. For some reason i thought there were two lines off the scavenger pump, but one is coming out of the head. The only line on top of the scavenger connects to the circled hose. The bolt pictured in the following link is whats installed in the top of the scavenger pump, which looks incorrect.

 

https://estore.subarupartswarehouse.com/p/Subaru_2010_Legacy-25L-TURBO-6MT-4WD-GT-Limited-Sedan/Turbocharger-Oil-Line-Bolt/49227607/15194AA420.html

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Got it. For some reason i thought there were two lines off the scavenger pump, but one is coming out of the head. The only line on top of the scavenger connects to the circled hose. The bolt pictured in the following link is whats installed in the top of the scavenger pump, which looks incorrect.

 

https://estore.subarupartswarehouse.com/p/Subaru_2010_Legacy-25L-TURBO-6MT-4WD-GT-Limited-Sedan/Turbocharger-Oil-Line-Bolt/49227607/15194AA420.html

 

 

I’ll take a look tomorrow to the bolt and photo it.

Worst case.. i have a 20g for ya if it ends up being the turbo [emoji51]

 

 

Sent from my iPhone using Tapatalk

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I should say i know its incorrect, based on the subaru parts diagrams. What is messing me up now is, what bolt belongs to the oil feed line located right next to the scavenger pump?

 

The options are number 1 (the link from the previous post)

 

Number 2 ( https://estore.subarupartswarehouse.com/p/Subaru_2010_Legacy-25L-TURBO-6MT-4WD-GT-Limited-Sedan/Turbocharger-Oil-Line-Bolt/49227605/15194AA270.html)

 

or Number 3 (pretty much 2 but with a screen/filter)

 

Subaru lists number one and number 2 as options for the feed line bolt.

Edited by Brett_dub
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Yes, but i ordered based on Subaru’s online parts diagram which has two options for the bolt in that location. Neither of the parts they listed had the filter, which is why I now have trust issues. I have that bolt, with the screen, and the bolt has the same protruding circle on the head.
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Yes, but i ordered based on Subaru’s online parts diagram which has two options for the bolt in that location. Neither of the parts they listed had the filter, which is why I now have trust issues. I have that bolt, with the screen, and the bolt has the same protruding circle on the head.

 

Subaru's parts diagrams chart lists 1004 for the difference between the 2 bolts, which is probably 10/04/2009 manufacturing date. I would check the manufacturing date of your car. I wonder if the earlier bolt does not work with BNR turbo and supplies too much oil.

 

I am pretty sure the scavenge pump top bolt on the other line does not have a dimple (filter). I had a moment when installing my 2011 GT's motor that I realized that I wasn't paying attention to the banjo bolts, so I checked them. [i looked through my pictures I don't have any in that area.]

 

I checked on my 2012. It is actually pretty easy to access without removing anything. Feed line has a circle recessed area. It feels like 15194AA420. The top bolt scavenge has no dimple.

Edited by dgoodhue
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