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A few weeks ago I stopped at a gas station and noticed blue/white smoke coming out of my hood-scoop. A quick inspection led me to believe it was the copper washer on the banjo-bolt going through the AVCS line and into the back of the block, in fact it was the AVCS line itself. A bit of research revealed that I wasn't the only one who had encountered this problem, but I still had difficulty getting the information and parts I needed for a fix in a timely manner, so when all was said and done, I decided to do this write-up.
Many people have problems with the turbo oil-feed line, as it is very easy to damage while working on or swapping turbos. However, this write-up is for replacement of the entire turbo oil-feed/AVCS line.
This is a pic of the line I'm talking about (without the section that runs under the manifold). The top section is technically the turbo oil-feed line, which mates to the AVCS line at the flare fitting.
The entire line runs from the top of the turbo (1), down to the back of the block (2), then under the intake manifold and around front to the AVCS unit (3) like so...
All three connections are banjo fittings/bolts, and all three are different. The turbo banjo-bolt is 10mm/1.5 thread pitch, and the bolt itself is a restrictor, as the hole in it is about the size of a ballpoint pin head (sorry, no pic). The AVCS banjo-bolts are both 12mm/1.25 thread pitch (metric), but slightly different from each other. Here's a closer look at these two bolts...
The bolt on the left goes around front to the AVCS unit, and has no filter, the one on the right goes to the back of the block, and contains a filter.
Here's a macro of the filter...
Removal of this filter is at your discretion, I reinstalled mine, and suggest (as Subaru would) you do the same. If you do reinstall the filter, make sure to blow it out before reinstallation to clear any contaminants that may be present.
My suggestion is that you re-use the turbo and block banjo-bolts, along with their respective copper crush-washers, and replace the AVCS banjo-bolt/fitting with the 90° metric fitting/hose in my parts list (64192016), installing a crush-washer between the AVCS unit and the fitting. The reason I used an after-market 90° fitting around front at the AVCS unit instead of the OE banjo-bolt/fitting was simply for ease of fittment.
NOTE: Some people have had sealing problems with using a single crush-washer on the banjo-bolt at the back of the block, requiring an additional washer to get a good seal.
The tools you'll need are:
- Dremel tool, or some sort of cutting device for the AVCS hard-line
- Ratchet w/long and short extension + 10mm, 12mm & 14mm
- 10mm, 17mm & 9/16 wrenches
- Flat-head screwdriver
- Shop towels
- Brakleen
The order of removal is:
- Negative battery terminal
- Air intake (2 10mm bolts)
- Airbox lid & bottom (flathead, 2 12mm bolts)
- Turbo heat-shield (3 10mm bolts)
- Passenger side up-pipe securing bracket (1 14mm nut, 1 14mm bolt)
- Cut AVCS line in front and back
- Front AVCS banjo bolt (1 17mm)
- Turbo banjo bolt (1 14mm)
- Block banjo bolt (1 17mm)
The parts you need are:
NOTE: Some prefer a 14" line instead of the 16" line I have listed above, either will work, but if you like things nice and tidy, go with the 14".
Once you get everything back in place, pull the coin holder out and look at the fuse chart on the back. Pull the one labeled IGN, mine was a yellow 12, but yours may be different. Crank the car a few times to prime the line and turbo, then replace the fuse. One other thing you should know is that my cruise control light started blinking 2 miles into my test drive, but turning the car off and back on again made it stop. I suspect it has something to do with the MAF being unhooked, but I'm not certain.
NOTE: When I put everything back together I left off the turbo heat-shield, and the up-pipe bracket so that when I took a short drive, I could see if anything was still leaking.
MANY THANKS to jnorth85 and lobelsteve for all the info and putting up with me .
Some random shots.
The weak silver solder that causes the problem. I haven't torn the line itself apart to see where the problem actually starts...yet.
agreed, nice job with the macro shots, very clear. That mesh in the banjo kinda scares me. Weren't there problems reported with those at some point, like some sort of service bulletin?
On a side note - that filter for the AVCS banjo bolt. Take it out. There's been a service bulletin on it.
As for your setup. Very sweet. -4 line should be just fine for the pressure to the turbo. The only change I would make is some kind of wrap on the lines if they are not coated with plastic. That exposed weave can very quickly turn into a saw with some vibration, and cut through all sorts of things it's touching.
On a side note - that filter for the AVCS banjo bolt. Take it out. There's been a service bulletin on it.
One different than the one above? Does it cause problems with non-sludged cars?
Quote:
Originally Posted by Turninconcepts.com
As for your setup. Very sweet. -4 line should be just fine for the pressure to the turbo. The only change I would make is some kind of wrap on the lines if they are not coated with plastic. That exposed weave can very quickly turn into a saw with some vibration, and cut through all sorts of things it's touching.
Excellent info, I'll look into it. Maybe a little heat-wrap in the places it's touching would do the trick.
Turbo oil-feed / AVCS line replacement 
.
