Is it possible to cap the oil drain fitting?
Thread Starter
Joined: Apr 2014
Posts: 18,643
Total Cats: 1,870
From: Beaverton, USA
I am in the process of prepping a motor to put in. It will be naturally aspirated for a few months then go turbo. I want to tap the oil pan while it is out but won't be ready to put a drain hose on. Can I use an NPT plug? Or a rubber hose cap over the hose barb?
Thread Starter
Joined: Apr 2014
Posts: 18,643
Total Cats: 1,870
From: Beaverton, USA
And can I cap an AN line? I'm taping the pan for 3/8th NPT, what size AN should I use?
Edit: Google revealed plenty of AN plugs so I just need a plug and a 3/8npt to AN adaptor.
Edit: Google revealed plenty of AN plugs so I just need a plug and a 3/8npt to AN adaptor.
3/8th NPT is the correct way to tap the pan. I picked up some 3/8th NPT to -8AN fittings from my local hydraulic shop. I also picked up a cap for the fitting that screws on. There is no issue running it capped.
Thread Starter
Joined: Apr 2014
Posts: 18,643
Total Cats: 1,870
From: Beaverton, USA
Is the general consensus here to use jb weld when sealing it, or Teflon paste. I know Teflon tape is frowned upon, but I also don't like the idea of unlubricated NPT threads.
I screw in my fitting, then lather jbweld all around the threads of the fitting. The FM manual says to apply a little jbweld to the threads and then screw it in and let it dry.
If you've got the motor out, the right answer is to TIG a weld-in NPT bung.
--Ian
Joined: Oct 2007
Posts: 6,029
Total Cats: 304
From: The coal ridden hills of Pennsylvania
Just an FYI.
Yes, I do agree with welding the fitting in though, only cause 1) "while motor is out", and 2) it's a metal to metal application, so why use an epoxy weld?
They do make fittings that aren't threaded...it just has a little nipple on that you drill a hole, insert the fitting, weld. That's the real way to do it. However, myself and 99% of mt.net used jb weld and screwed our fittings in without any issues for years.
Joined: Oct 2007
Posts: 6,029
Total Cats: 304
From: The coal ridden hills of Pennsylvania
Yes, the pan is cast aluminum. That's why you buy one of these and take it to a pro TIG welder:
http://www.summitracing.com/parts/sum-220072
That's what I'm doing right now -- the motor is out of the car for a rebuild, and I'm tired of having the entire bottom of the car covered in oil leaking from this fitting. I thought about trying to DIY the welding with the spoolgun for my Miller 211, but welding cast aluminum oil pans is supposed to be a real bitch due to the pores having soaked up oil. Everyone says this is a job for a pro, and I'm definitely not that good with a welder.
--Ian
http://www.summitracing.com/parts/sum-220072
That's what I'm doing right now -- the motor is out of the car for a rebuild, and I'm tired of having the entire bottom of the car covered in oil leaking from this fitting. I thought about trying to DIY the welding with the spoolgun for my Miller 211, but welding cast aluminum oil pans is supposed to be a real bitch due to the pores having soaked up oil. Everyone says this is a job for a pro, and I'm definitely not that good with a welder.

--Ian
I agree that if the motor is out, then TIG welding it in is the correct way to do it. With the motor in the car, I will deal with putting on more jbweld if it ever cracks and leaks.
Track speed welded in a 1/2" NPT bung for my pan for the oil drain. I ran it for break in with a plug in it then added my NPT to AN fitting after that when I added the turbo. I later added my own 1/8" NPT bung for my oil temp sender. That summit bung is surprisingly cheap. I didnt even think to check there when I bought my 1/8" bung I just went with a 1/2 coupling from mcmaster.
With the motor out, you could weld in a ORB port bung like this one. It gets rid of the NTP threads and it it ever leaks just change the o-ring.
-10 AN Weld Bung, Female O Ring Boss ORB - Sweet Performance Products, Inc - (Powered by CubeCart)
-10 AN Weld Bung, Female O Ring Boss ORB - Sweet Performance Products, Inc - (Powered by CubeCart)
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