I NEED HELP FROM THE PROS! stripped oil pan thread

[128ibro]

What's the best and safest way to repair stripped oil pan drain threads on our cars without replacing the whole oil pan. I have 128i N51

[Shortedaman]

Originally Posted by 128ibro

What's the best and safest way to repair stripped oil pan drain threads on our cars without replacing the whole oil pan. I have 128i N51

a big heli coil. but it might leak afterwards.

[Edrift]

If you remove the pan surely you could drill and tap a new thread without replacing the pan?

I wouldn't drill anything with the pan still on unless you want shavings in your engine.

Alternatively could you weld a nut on top of the existing drain and then you can fit a smaller plug?

[Gray_Panther]

Just replace the oil pan and gasket. The engine will be drained of oil anyways with whatever option you go with.

[crowtrobot]

Originally Posted by Gray_Panther

Just replace the oil pan and gasket. The engine will be drained of oil anyways with whatever option you go with.

Hopefully it's an auto, N51/52 manual pans are hard to come by and $$$ new. Found that out the hard way after one of my oil level sensor studs snapped...

[iminhell1]

I'd just go with an oversized drain plug and don't overtighten it.

[dtla1]

See if you can rent the appropriate tap to try to re-tap the threads, use a strong magnet to get any filings from that that you can (wait, the pan is aluminum isn't it?), then replace with a drain valve so you don't need to worry about the threads in the future.

[JM98]

Its an easy fix, just retap the hole and use a new plug. If its really trashed you can go up 1 size with the only difference being that you'd have to drill the hole to the larger size.

Regardless, its a 10 minute process.

[JimD]

The pan on my 2009 manual transmission N52 is steel. The pan on options are to:

1) run a normal sized tap through the threads and make sure they are not salvagable. Grease the tap.

2) If unsuccessful, put in a heli coil or try tapping threads for a larger plug. You may want to look for a special drain plug that will make new threads which would be a bit of a quick and dirty way to do this. But you risk putting metal into the engine.

3) Pull the pan. That lets you easily set it up for a new drain plug. You could also possibly have a really good welder (assuming an aluminum pan) build up some metal to drill and tap for a normal drain plug. The hard thing would be getting it clean. Or you could have a nut welded on. Again it has to be clean.

I would probably helicoil it with the pan off. The helicoil is threaded into pan and staked into position. Correctly done it should not leak. It gives you steel threads for the drain plug.

[128ibro]

Originally Posted by JimD

The pan on my 2009 manual transmission N52 is steel. The pan on options are to:

1) run a normal sized tap through the threads and make sure they are not salvagable. Grease the tap.

2) If unsuccessful, put in a heli coil or try tapping threads for a larger plug. You may want to look for a special drain plug that will make new threads which would be a bit of a quick and dirty way to do this. But you risk putting metal into the engine.

3) Pull the pan. That lets you easily set it up for a new drain plug. You could also possibly have a really good welder (assuming an aluminum pan) build up some metal to drill and tap for a normal drain plug. The hard thing would be getting it clean. Or you could have a nut welded on. Again it has to be clean.

I would probably helicoil it with the pan off. The helicoil is threaded into pan and staked into position. Correctly done it should not leak. It gives you steel threads for the drain plug.

I just got longer bolt and it's holding well for now with the few threads that left on the back of the fan. Tapping a bigger size is risky and it'll never seat like the way it was.

[128ibro]

Originally Posted by Gray_Panther

Just replace the oil pan and gasket. The engine will be drained of oil anyways with whatever option you go with.

Not worry about the oil to be drained at all. I don't want to buy new oil pan $800 and go through the whole process.

[Tommm]

Get a stahlbus drain valve. install it once and never worry about the screwed up threads.