What is the "ideal" way to do the oil drain line? - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


DIY Turbo Discussion greddy on a 1.8? homebrew kit?

Reply
 
 
 
LinkBack Thread Tools
Old 04-12-2009, 05:37 PM   #1
Junior Member
Thread Starter
 
kday's Avatar
 
Join Date: Aug 2008
Location: Boston
Posts: 223
Total Cats: 0
Default What is the "ideal" way to do the oil drain line?

I have seen how it is done with a drill and tap. It seems to me that is a compromise given that the pan is so hard to remove that nobody wants to do it just to add the oil drain. But my engine is on a stand and the pan is already off.

Welding a bung might be nice but I can't weld aluminum.

Why is the usual location so far forward? Is there interference from something otherwise? Obviously where a straight shot down from the turbo ends up will vary depending on the manifold design, but with my non-exotic cast manifold, a straight down oil return will end up right around the rearmost part of the shallow end of the oil pan. The FM instructions (for example) show the drain all the way at the front of the pan. What am I missing here?

This bulkhead fitting seems like a good alternative to a tapped hole and the usual brass fitting.
kday is offline   Reply With Quote
Old 04-12-2009, 05:51 PM   #2
Elite Member
iTrader: (24)
 
kotomile's Avatar
 
Join Date: Oct 2006
Location: Monterey, CA
Posts: 7,578
Total Cats: 40
Default

This is why it's so far forward:

Name:  img009.jpg
Views: 46
Size:  64.3 KB

Here's what I used:

Name:  img015.jpg
Views: 47
Size:  89.6 KB
kotomile is offline   Reply With Quote
Old 04-12-2009, 05:58 PM   #3
Junior Member
 
Join Date: Apr 2009
Location: Auckland, New Zealand
Posts: 50
Total Cats: 0
Default

there is a baffle plate running along the side of the pan wich you will hit if you drill further back even drilling at the front you have to watch the oil pickup pipe if you drill in too far if your engines out take your sump to an engineer they will gladly weld a alloy fitting on for you

here is why
Attached Thumbnails
What is the "ideal" way to do the oil drain line?-gyugugkyfgfj.jpg  
sprsta is offline   Reply With Quote
Old 04-12-2009, 05:58 PM   #4
Elite Member
 
Join Date: Feb 2008
Location: Victoria, BC
Posts: 2,322
Total Cats: 12
Default

I would just take it to someone who welds aluminum. I can't see a shop charging more then $30 to weld a bung onto it.
dustinb is offline   Reply With Quote
Old 04-12-2009, 06:05 PM   #5
Antisaint
iTrader: (17)
 
Vashthestampede's Avatar
 
Join Date: Feb 2007
Location: Danbury, CT
Posts: 4,659
Total Cats: 54
Default

Drill and tap it like FM shows, up in the front. Then thread it in with some JB weld around it.
Vashthestampede is offline   Reply With Quote
Old 04-12-2009, 06:56 PM   #6
Newb
 
Join Date: Apr 2009
Location: So Cal
Posts: 13
Total Cats: 0
Default

nice pictures..really helps me out.
Jo3L is offline   Reply With Quote
Old 04-12-2009, 11:00 PM   #7
Junior Member
Thread Starter
 
kday's Avatar
 
Join Date: Aug 2008
Location: Boston
Posts: 223
Total Cats: 0
Default

Hmm. Thanks for the pics. The pickup tube might make it very difficult to put a drain directly below the turbo. (Though I suppose a bung could be welded such that there was no internal clearance needed.)

What about mounting the drain in the deep part of the pan, on the side of the sump? Seems like it would result in a shorter drain line with less angle.
kday is offline   Reply With Quote
Old 04-12-2009, 11:04 PM   #8
Murderator
iTrader: (76)
 
18psi's Avatar
 
Join Date: Apr 2008
Posts: 36,192
Total Cats: 2,583
Default

Quote:
Originally Posted by dustinb View Post
I would just take it to someone who welds aluminum. I can't see a shop charging more then $30 to weld a bung onto it.
I SURE CAN!! Do you know the prices to weld aluminum? You will be surprised, the gas and wire required to weld it is quite pricey
18psi is offline   Reply With Quote
Old 04-12-2009, 11:05 PM   #9
Elite Member
iTrader: (24)
 
kotomile's Avatar
 
Join Date: Oct 2006
Location: Monterey, CA
Posts: 7,578
Total Cats: 40
Default

You're overthinking it man. Just put it up front like everyone else, you're not going to get any more flow by ensuring it's exactly straight up and down.

Here's mine (seems I've been posting this pic a lot lately!), it's not dead-on 180* but it does not want for flow!
Name:  img018.jpg
Views: 244
Size:  74.9 KB

Edit - Besides, think about it, your feed line is likely 1/3rd the size of the drain, and is probably restricted in some way.

Last edited by kotomile; 04-12-2009 at 11:55 PM.
kotomile is offline   Reply With Quote
Old 04-12-2009, 11:44 PM   #10
Junior Member
iTrader: (7)
 
Join Date: Mar 2007
Location: Texas Panhandle
Posts: 213
Total Cats: 0
Default

I had the oil pan off so I had a bung welded. It cost $40 plus the bung from summit which I think was like $5. It's not necessary at all to have a bung welded, but I just felt like over doing it.
jsisco is offline   Reply With Quote
Old 04-13-2009, 12:18 AM   #11
Junior Member
 
Join Date: Apr 2008
Posts: 350
Total Cats: -2
Default

Quote:
Originally Posted by kday View Post
This bulkhead fitting seems like a good alternative to a tapped hole and the usual brass fitting.
The failure mode that part would be the nut coming off in the pan, and having to drop the pan to get that loose metal out of your engine. I would only use a bulkhead fitting with an externally-tightened nut.

Since the pan is off, a welded fitting is your best option. If the aluminum isn't cleaned really, really well, there's a high risk of porosity that could cause an oil run. So clean it really, really well and take it to a good shop.

Assuming it doesn't have a negative impact on packaging or access to turbo fasteners, etc., the shortest run possible is generally a good way to go. Moving it slightly forward of the turbo so the hose doesn't block tool access to the drain fittings and stuff might be a good idea.
SolarYellow510 is offline   Reply With Quote
Old 04-13-2009, 12:02 PM   #12
Junior Member
Thread Starter
 
kday's Avatar
 
Join Date: Aug 2008
Location: Boston
Posts: 223
Total Cats: 0
Default

Re: overthinking it, yes, probably. But I would prefer the neatest solution and I have the time to do it right. I need to make sure the engine mount won't be in the way though, your pic makes that clear.

Re: failure modes with the nut inside - I would safety wire it if I did it. Right now I am leaning towards having a bung welded. I need to find a good welder anyway, since my cast manifold has a crack in it. But I'm sure it will cost me more than $30. Skilled labor is not cheap in these parts...
kday is offline   Reply With Quote
Old 04-13-2009, 04:42 PM   #13
Junior Member
 
Join Date: Feb 2009
Location: Oregon
Posts: 120
Total Cats: 0
Default

Since you are having the manifold crack welded anyhow, I would go ahead and have the bung welded to the oil pan - my guess is it's gonna be pennies to dollars.
b0ne is offline   Reply With Quote
Old 04-13-2009, 09:40 PM   #14
Supporting Vendor
iTrader: (31)
 
Savington's Avatar
 
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 14,366
Total Cats: 1,327
Default

Quote:
Originally Posted by 18psi View Post
I SURE CAN!! Do you know the prices to weld aluminum? You will be surprised, the gas and wire required to weld it is quite pricey
I had it done. Cost me $40 because he had to clean the oil pan out first. I wasn't surprised.

You want legit? This is it:

Name:  DSCN1305.jpg
Views: 53
Size:  60.5 KB
Savington is offline   Reply With Quote
Old 04-13-2009, 11:48 PM   #15
Junior Member
Thread Starter
 
kday's Avatar
 
Join Date: Aug 2008
Location: Boston
Posts: 223
Total Cats: 0
Default

That's the ticket. Perfect. Would you choose the 45 degree AN hose end again? Is that -10 or -12?
kday is offline   Reply With Quote
Old 04-16-2009, 11:32 PM   #16
Elite Member
iTrader: (8)
 
Join Date: Dec 2008
Location: Kingston, Ontario
Posts: 2,791
Total Cats: 71
Default

i assume so his oil line is more linear.
shlammed is offline   Reply With Quote
Old 04-17-2009, 07:43 AM   #17
Junior Member
iTrader: (1)
 
Join Date: Aug 2008
Location: Granada, Spain
Posts: 336
Total Cats: 2
Default

kday, has your car AC or PS? Maybe in the 90 NA is easier to route, but take a look at the 2001+ with AC and PS

Name:  PICT0063.jpg
Views: 45
Size:  98.3 KB
ismael_pt is offline   Reply With Quote
Old 04-17-2009, 09:20 AM   #18
Junior Member
Thread Starter
 
kday's Avatar
 
Join Date: Aug 2008
Location: Boston
Posts: 223
Total Cats: 0
Default

haha, yes, that is pretty crowded. I have a 96 engine that is going into the 90 and I'll most likely remove AC and PS.
kday is offline   Reply With Quote
Old 04-17-2009, 01:34 PM   #19
Supporting Vendor
iTrader: (31)
 
Savington's Avatar
 
Join Date: Nov 2006
Location: Sunnyvale, CA
Posts: 14,366
Total Cats: 1,327
Default

Kday, buy a 60 degree fitting. I did the 45 but most people have interference issues with the steering rack. Mine BARELY clears. It's a -10AN fitting. I also used nylon braided line so I don't cut myself every time I look at it. If you're using a BEGi manifold, you should only need a foot (I took 2ft of -10AN and ended up using 8") since you aren't going down to the front of the motor.
Savington is offline   Reply With Quote
Old 04-17-2009, 03:12 PM   #20
Junior Member
Thread Starter
 
kday's Avatar
 
Join Date: Aug 2008
Location: Boston
Posts: 223
Total Cats: 0
Default

Cool, I'll get the 60 degree fitting. I have a bunch of -10 stainless braid hose left over from another project. I'll try not to look at it too much...
kday is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 58 12-13-2017 10:04 PM
OTS Bilstein to motorsports ASN conversion stoves Suspension, Brakes, Drivetrain 5 04-21-2016 04:00 PM
Back to Stock Part Out!! Turbo Parts, MS2 Enhanced 01-05, Suspension, and MOAR! StratoBlue1109 Miata parts for sale/trade 16 10-02-2015 10:39 AM
Moroso Air Oil Separator Catch Can Aroundcorner Miata parts for sale/trade 2 10-01-2015 04:20 PM
Low oil pressure after 1.8 swap and new turbo setup JesseTheNoob DIY Turbo Discussion 15 09-30-2015 03:44 PM


Thread Tools

Posting Rules
You may not post new threads
You may not 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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 04:43 AM.