Drilling NB return on the car
#22
Retired Mech Design Engr
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I used a step drill that fits the small chuck. The aluminum pan cuts easily. Conversely, drill bits can be turned down. As they are case hardened, you will lose a lot of strength, but, again, the aluminum is easy to drill.
#25
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Shorter may not be better, due to A/C bracket. That's where I rubbed my chuck a little using the short step drill. I think the one I linked to, with the angle drill, would be ideal.
Waiting for Lars' pictures.
Waiting for Lars' pictures.
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Have you ever looked at the bottom of a miata's engine bay? To remove the oil pan you have to lift the engine up a good amount to get clearance around the subframe. Then you have to attempt to put it and the windage tray back on upside down with a subframe in the way. With the amount of effort that would take, you might as well pull the engine and then do it properly.
#34
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I used a Christmas tree drill bit (Step drill bit) to drill mine. It was EXTREMELY EASY to drill. Then used a 1/2 NPT tap, all from Harbour Freight. This was when the engine was out of the car. I also somehow managed to drill in the wrong spot the first time... On the opposite side of the pan... Plugged it with a 1/2 NPT plug from Home Depot. Not a single drop has leaked. I am going to convert over to a -10 AN this winter however. I did use a dab of loctite on the threads, I thought it may prevent leaks.
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