What's the best way to fix rthis? Don't wanna' flub it up..

[geemann51]

My swapmeet special aluminum oil pan (sbc 350) is leaking liberally at the drain plug, looks like it was a botched repair because of the 15mm bolt that replaces the original plug. It's obviously stripped and provides little bight before spinning loosely upon tightening.

I figure I am going to have to tap up to a larger diamater bolt. It should be pretty simple, but I don't want to screw up and make the situation worse. Is ther anything I should keep in mind or is there an easier fix that I am overlooking? Thanks.

[30tudor]

Any auto parts store in town will have oversize, self tapping drain plugs.

[geemann51]

Seriously? Thanks, I'll give a try....

[Greazer]

If the botched drain hole happens to be too big to use a self tapping drain plug, you might consider using a "HeliCoil" insert.

VW recently used them when they went with a steel drain plug, but an aluminum oil pan. (The hard steel would gall the soft aluminum and mess up the threads after a number of oil changes). A HeliCoil insert was the official recommended repair.

[desertratrodder]

YES YES Heli coil..as long as you dont tighten the plug like superman, you should be able to service the oil for a long time. Sometimes they unscrew with the drainplug, so just put in another.

[38Chevy454]

Are you sure it's a 15 mm metric bolt? Because that is like 5/8 inch. A helicoil would not take up that much if you go back to a 1/2 inch bolt. For reference 1/2 inch is equal to 12.7 mm.

I agree that a helicoil is the right way to fix it. Just get the right size to work with your hole in the oil pan.

[DrJ]

There's another insert you could use called a Keen-sert which wont come out with the plug because it has four small stakes built into it that you hammer in and stake the threads so it can't come out.

[geemann51]

Thanks for the responses. I will first try an oversized self tapper, but where can I get a helicoil or a keen-sert, NAPA have em'? Thanks again.

[CTFuzz]

The DR is correct, Keen sert is the way to go. Problem is you need to buy a kit that includes a tap and instalation tool, for some this may be a little costly...........