What size for turbo oil return line??

[DieselsRcool]

Will a 3/8" aluminum tube work OK for the turbo oil return? I have welded, drilled and tapped the pan. Now I'm thinking flared tubing for the line. I have 3/8 aluminum or 1/2" copper. Seems the 3/8 should be big enough or do these lines have a tendancy to sludge up and so should be bigger.
Thanks all!

[dieseltech]

3/8 of an inch is too small.  On all the custom turbo setups I have done, I found one important lesson: NEVER have any pressure on the oil return line.

It can and will blow the seals clean out of the turbo.  You want to get the return pipe as close to the size of the return port on the turbo, and have a min of 4" vertical drop before making any turns. I would say 1/2 of an inch to be about the min safe size. Use a metal that is not brittle. There needs to be flex between the turbo and the pan; there is a lot of vibration and expanding and contracting with heat, too.  Here is a tip. Go to the junkyard and LOOK at the cars with turbos, see how the return is made and the size of it, get some ideas, then go at it.  Lots of Saabs are turbo, some Volvos, and a few other cars, but check 'em out. you ma even be buying the return line off of a Saab and making it fit your car!

Best of luck. If you want some pics of turbo setups I have done to get ideas, let me know. I will post them.

chris

[HughF]

Use a short length of silicone hose between the output barb on the turbo and the input barb on the sump. I service some Saab 9000 turbo's here in the UK, and they use this technique with great success.

Hugh

[DieselsRcool]

OK, Thanks for the tips guys.

I got some high temp Aeroquip hose, 1/2"id and some brass barbs. I'll keep the bends smooth to ease the flow.

Thanks again.

[fatmobile]

 I used 5/8"/16mm OD tubing for my turbo oil return line.
And 5/8" silicone heater hose.
Bumped,... from page 571.