Turbo Oil return line need some info help please

[1987T]

I have a section of -12 Line and I also have the piece that bolts to the bottom of the turbo. What Im looking for is what size fitting do I need to go into the block? And lastly will -12 fit ? I was going to go -10 but I have a lot of -12 Fittings already just not one that will go in the block. My original oil return line will not seal to the bottom of the turbo any more and The thought of just going as big as I can to help the oil return properly and not leak.
-12 Might seem like over kill to some but it what I used on my Turbo mustang do to the 40-80 psi of oil pressure it had. Well my Engine in my T is now the same 85PSI cold and well over 40 psi most of the time under hard acceleration Im seeing 80psi and Im guessing this is hwy I cant keep a gasket in the factory line also tried Red RTV worked for one ride and leaking again

Again the only thing Im short on it the fitting to go in the block. I just need to know what size the thread is so I can get a fitting for it. Just hoping it will fit ok.
Thank you very much for your help

 

[grass doctor]

yes it is a special brass fitting in stock applications unsure o size but at interesting

 

[salvageV6]

https://www.turbobuick.com/threads/oil-return-fitting-size.349677/

 

[No disintegrations]

A good stock line fits best and has a huge diameter which is helpful since the oil is a foam-like mess as it exits the turbo. Needs the big diameter. An fittings are bulky and space is tight under the turbo.

 

[1987T]

Thanks guys Building one today

 

[dank GN]

The hole in the block is 3/4npt FYI . The only reason I know is because I had to buy a big drill bit and tap to tap acouple 109 blocks .

 

[dank GN]

And the bigger the better as far as turbo drain line . The minimum size would be a -10 an line though.

 

[Bullnerd]

Just curious, What's wrong with the stock one?

 

[1987T]

Just curious, What's wrong with the stock one?

My factory one is not sealing at the turbo pretty sure its twisted wrong as it press really tight on the back side near the block and wants to be away at the front. Hard time getting bolts in it and keeps leaking at the very front portion. It seals for a bit but after 2 -3 runs its leaking again and the bolts are still tight. The one gasket I removed was so flat at the back side it split where the bolt goes threw it and the front I could see the line where it was leaking threw the side, Tried Red RTV and a gasket still leaked tried just red atv still leaked, just done with this and want it sealed for the long haul. Season here in Mi is almost over and ID like to drive this thing a few more times without coming home to an oil mess under the hood all over the Cross member lower rad hose oil filter cooler lines steering on the right side. You get my point I think.

 

[No disintegrations]

The flange is most likely not flat anymore.

 

[TurboTGuy]

Here. Be done with it.

https://www.ebay.com/itm/86-87-Buic...e=STRK:MEBIDX:IT&_trksid=p2060353.m2749.l2649

 

[Bullnerd]

My factory one is not sealing at the turbo pretty sure its twisted wrong as it press really tight on the back side near the block and wants to be away at the front. Hard time getting bolts in it and keeps leaking at the very front portion. It seals for a bit but after 2 -3 runs its leaking again and the bolts are still tight. The one gasket I removed was so flat at the back side it split where the bolt goes threw it and the front I could see the line where it was leaking threw the side, Tried Red RTV and a gasket still leaked tried just red atv still leaked, just done with this and want it sealed for the long haul. Season here in Mi is almost over and ID like to drive this thing a few more times without coming home to an oil mess under the hood all over the Cross member lower rad hose oil filter cooler lines steering on the right side. You get my point I think.

Makes sense. I didn't mean you specifically, just in general.

Anyone make an o-ring gasket for this application?

 

[salvageV6]

It's a big drill but still 1/2" NPT thread.

Takes a 23/32" or 1.7188" drill size, big almost 3/4" hole.

 

[salvageV6]

https://www.pegasusautoracing.com/productselection.asp?Product=3250

Has -12 male fitting for a completed hose you can screw onto it that goes to the 1/2" NPT pipe fitting that would go into the block.

They also have a page with adapters for THEIR raw -12 hose to 1/2" NPT direct if the hose isn't made up yet with any fittings on it.

https://www.pegasusautoracing.com/productselection.asp?Product=3497-050

Note the picture above has a flared pipe corrugated hose screwed into the adapter with the 1/2" NPT threads on it, it's two pieces.

 

[1987T]

So I have attached what I came up with. Its -12 Teflon Braided Areoquip hose. I ended up using some old industrial Hose Clamps I got from my Father they really Clamp down on the hose nice. (Need to pull it and paint them black will get to that soon) I used 2 water hose fittings I found at the local Napa store. They were 1/2" NPT To 5/8" Barbe (guessing they are for water lines on a car or truck) They are 1.5" Long each and had a nice bump on the end for the clamp to grab. Im not sure I have the curve 100% yet I was way long on the 1st one and it had a bad low spot so pulled cut a 1/4" Off and still felt it was dropping to low. Cut another 1/4" Or so off and I think I have it but we will see what happens. Im quite sure it will not leak any more. I also Opened the end at the top up as much as I could so it has a very large hole for the oil to drain into. (Sorry didnt think to take a photo before I put it on the turbo) Its got a gasket and light coat of Red RTV since the gasket had a hair line crack in the one side I just wanted to make sure it wouldnt leak. I filled the crack with RTV and then a very very thin coat over the top let it set over night and then a very thin coat over the top and stuck it to the turbo. If this leaks I think im just done with it. Spent the better part of 4 hours working on just this one thing today. Man time sure flies or Im just getting really Freaking OLD!

If anyone sees any thing wrong angles jacked what ever let me know your thoughts Im still concerned it doesnt have enough slope to it.

 

[salvageV6]

You could have done 3/4" hose barb as well, no restriction.

GHBM075-050 - Bluefin GHBM075-050 - 3/4" Hose Barb x 1/2" Male Brass Pipe Adapter

Bluefin GHBM075-050 - 3/4" Hose Barb x 1/2" Male Brass Pipe Adapter - 3/4" Hose Barb x 1/2" Male Brass Pipe Adapter

www.supplyhouse.com

 

[1987T]

So Far so good no Oil Smoke out the exhaust under boost and no more leaks!