Drain plug stripped

After sinking my 03 yz450 and flushing the oil 6+ times my case oil drain plug won't tighten. Should I leave it or fix it?

buy new plug and clean the thread ;)

Always fix it.  Best option is a TimeSert. HeliCoils are OK, but not as suitable.

It's certainly not the sort of bolt you want to fall out.

The drain plug thread is M10 with a fine pitch iirc, with not a huge amount of metal casing around the area.

In the past for simplicity, I've just tapped out the casing to a slightly larger 7/16 UNF thread and sourced a corresponding drain plug.

The first start tap can cut new thread without the need for any drilling.

Orientate the engine so gravity won't allow any cuttings to fall inwards, grease tap flutes to catch the cuttings, and remove and clean the tap regularly as you cut the new thread. Once the new thread is completed you can then clean out any small amount of residual swarf with a cotton bud. No need to flush or split casings if you work carefully.

It's certainly not the sort of bolt you want to fall out.

The drain plug thread is M10 with a fine pitch iirc, with not a huge amount of metal casing around the area.

In the past for simplicity, I've just tapped out the casing to a slightly larger 7/16 UNF thread and sourced a corresponding drain plug.

The first start tap can cut new thread without the need for any drilling.

Orientate the engine so gravity won't allow any cuttings to fall inwards, grease tap flutes to catch the cuttings, and remove and clean the tap regularly as you cut the new thread. Once the new thread is completed you can then clean out any small amount of residual swarf with a cotton bud. No need to flush or split casings if you work carefully.

Thanks I will try it!!

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