Oil drain fitting
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From: Toronto, ON
Hey guys,
I am having a really hard time finding a 3/8 NPT tap locally. Are these not popular? Is there a metric equivalent fitting I can use for the oil drain instead of NPT stuff? Are there metric threaded to barb fittings? I'm guessing M14 x 1.5 would be roughly similar.
Thanks.
I am having a really hard time finding a 3/8 NPT tap locally. Are these not popular? Is there a metric equivalent fitting I can use for the oil drain instead of NPT stuff? Are there metric threaded to barb fittings? I'm guessing M14 x 1.5 would be roughly similar.
Thanks.
they should be quite popular...
If you have any friends that are Plumbers/Steamfitters/Pipefitters with tools, they'll have it.
But your local Auto/Truck parts store should have it
If you have any friends that are Plumbers/Steamfitters/Pipefitters with tools, they'll have it.
But your local Auto/Truck parts store should have it
FWIW I had trouble finding one locally here too. San Antonio is not a small town either so there are lots of stores for that sort of thing. I was surprised I had that much trouble. Grainger had one at $80 but I passed on that. I finally resorted to borrowing one from a machinist buddy of mine.
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From: Chicago. (The less-murder part.)
Yeah, if you want to find it locally, you'll need to track down a proper tool store.
Alternately, Enco has 'em for $6.33: Enco - Guaranteed Lowest Prices on Machinery, Tools and Shop Supplies Pretty sure they ship to Canada.
37/64 drill is $9.03: Enco - Guaranteed Lowest Prices on Machinery, Tools and Shop Supplies
When I did mine, however, I used the 9/16 section of a step drill (aka Uni-Bit), as the 37/64 I bought was too long and also didn't fit into the chuck of my right-angle drill. The pan is soft and thin, so it works fine.
Alternately, Enco has 'em for $6.33: Enco - Guaranteed Lowest Prices on Machinery, Tools and Shop Supplies Pretty sure they ship to Canada.
37/64 drill is $9.03: Enco - Guaranteed Lowest Prices on Machinery, Tools and Shop Supplies
When I did mine, however, I used the 9/16 section of a step drill (aka Uni-Bit), as the 37/64 I bought was too long and also didn't fit into the chuck of my right-angle drill. The pan is soft and thin, so it works fine.
Keep in mind the 14mm tap you referred to is NOT a tapered thread, like the NPT taps (national pipe taper), and will NOT seal. Use that crappy tap Joe linked.
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From: Toronto, ON
I was able to find a 3/8 NPT at a tiny shop in the ghettos this morning. I'm gonna have to go with a 9/16" bit though.
9/16" should work, its only .0156" smaller. Just be sure you don't tap it too far, the general rule of thumb is that a proper NPT thread is made after 2/3rds of the tap has been threaded into the hole. After that you're supposed to use a thread gauge, but we just use our fittings, and make sure they don't go in too deep. Be careful though, if you're not exactly 90* or if you use a slightly bigger drill or WHATEVER, and the hole and threads are sloppy, you won't have to go in as far with the tap before the fitting bottoms out. If that makes any sense to you I'm impressed.
I think I used a 9/16" drill on mine as well. WRAP A THICK LAYER OF TAPE AROUND THE DRILL BIT AS A DEPTH STOP. If you do not have something to stop the bit it could grab and get pulled into the oil drain tube. The pan is thin so you only need to drill in about 1/4" or so.
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From: Toronto, ON
Thanks for the tips guys. I was able to get it all drilled and tapped today. I went really slow with the drilling and had someone help me steady the drill so that I didn't have to put too much pressure on it. I flushed it with 8L of mineral spirits and only found a couple very small shavings. I also pressurized the crankcase with 5-8psi. I haven't filled it up with oil or started it yet, as the JB Weld is still curing. I also removed the PS line to make some extra room.
My old drill was only able to accept a 3/8" drill bit so I had to race out to the store to get a drill with a 1/2" chuck. Got there just before it closed!
My old drill was only able to accept a 3/8" drill bit so I had to race out to the store to get a drill with a 1/2" chuck. Got there just before it closed!
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