Turbo oil-feed / AVCS line replacement - Page 36 - Subaru Impreza WRX STI Forums: IWSTI.com
STI Forum
Start New Thread Create Account Advertise FAQ Members List Contact
Turbo oil-feed / AVCS line replacement
Turbo oil-feed / AVCS line replacement
Go Back   STI Forums > > > Turbo oil-feed / AVCS line replacement
Thread Tools
Old 12-14-15, 02:22 PM   #351
S204 Racer
Feedback Score: 0 reviews
Car: '06 Lotus Exige
My Subaru Parts for sale

Join Date: Apr 2005
VisualEchos is on a distinguished road
Default Re: Turbo oil-feed / AVCS line replacement

I can't believe this thread is still going. I haven't even owned an STi since '09 and I'm still getting PM's! lol
VisualEchos is offline  
Likes 0 Dislikes 0
Reply With Quote
Sponsored Links
Old 10-13-16, 11:42 AM   #352
Becoming A Contributor
Feedback Score: 0 reviews
Car: 13' Pearl White, WRX
Fav Mod: Carbon
My Threads
Posts: 12
My Subaru Parts for sale

Join Date: Nov 2012
Location: JAPAN
itiswhatitisnt is an unknown quantity at this point
Default Re: Turbo oil-feed / AVCS line replacement

A leak could be caused from the "Copper Washers" being over torqued. Copper is soft...it can leak from the washer being "crushed" causing a leak from the top of the banjo bolt.

My technician explained and physically showed me the issue and how it got fixed.
itiswhatitisnt is offline  
Likes 0 Dislikes 0
Reply With Quote
Old 02-26-17, 05:06 PM   #353
John Peter
Joined the Conversation
Feedback Score: 0 reviews
Fav Mod: Coming Soon
My Threads
Posts: 1
My Subaru Parts for sale

Join Date: Feb 2017
John Peter is an unknown quantity at this point
Default Re: Turbo oil-feed / AVCS line replacement

Originally Posted by VisualEchos View Post
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.

Image Link

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...

Image Link

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.

Image Link

Here's a macro of the filter...

Image Link

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:

Image Link

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.

Image Link

Image Link

The front AVCS line when cut + new fitting/hose.

Image Link

The new line installed.

Image Link

If you have any questions just ask .
Can I just drill out the restrictor and remove the filter from the block banjo fitting to get better oil flow to the turbo?
John Peter is offline  
Likes 0 Dislikes 0
Reply With Quote
Sponsored Links

Thread Tools

Posting Rules
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

New To Site? Need Help? More

All times are GMT -8. The time now is 04:58 PM.

Powered by vBulletin
Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Designed & Powered by Domain Architect
vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2019 DragonByte Technologies Ltd.