How should this oil pan be fixes? Possible?

[88Sedan]

I have my oil pan removed and now I can see why the drain plug has dripped since I bought the car last year. In the picture you can see someone in the past did some kind of thread repair and unfortunately they didn't drill or insert the steel thread repair perpendicular to the sealing surface for the crush washer.

With brand new crush washers it leaks at 18 ft/lbs because the washer isn't compressed evenly and since the drain plug is NOT perfectly centered a some of the washer is barely on the sealing edge of the pan.

Is this fixable? How? Because labor costs are so high I don't know if it even makes sense to have a machine shop fix this. I am uncomfortable torquing higher and I'm positive it wouldn't help anyways.

For a pan that is otherwise perfect this really sucks to potentially have to source another pan. I know it doesn't look awful in the pictures but trust me this thing won't seal correctly until something is done. Open to ideas....

[roguetoaster]

Since you have the pan off why not just replace it with a new one?

[88Sedan]

I was hoping to avoid that, but it is certainly an option. I will admit I don't like throwing away old parts and the pan is so clean otherwise I would like to at least attempt some sort of repair.

[MrBurgundy]

just replace it. it's kinda a PITA to take out so why risk it?

[E30SPDFRK]

You could use a thicker plastic washer that will crush and deform more at 18ft/lbs.

M20 pans are available new on the aftermarket now for reasonable prices if that doesn't work.

[88Sedan]

That's worth trying for sure. I wonder if I can find those locally or if I'll have to order online. I appreciate the idea.

[e30davie]

You can get washers that have a rubber bit on them, they use them in hydraulics. they call them "bonded washers"

I'm not sure how thick the rubber bit is, but might be worth a go.

https://www.sealsolutionsaustralia.com.au/product/dowty-sealsbonded-washers/

[TobyB]

Find a spotface milling bit, get it with the right sized pilot to run in the existing threads, and reface the sealing surface.

Then it'll be perpendicular.

That's the machinist's way.

Of course, you can buy a LOT of these:

https://www.pegasusautoracing.com/productselection.asp?Product=3245

for the price of one spotfacer if you're looking for an 'alternate solution'.

t
would fixture it up in the mill, bore out the threads, and replace the entire drain plug with a fire hydrant.
Because he made the handle to open fire hydrants once, and it was lots of fun... and only slightly illegal.