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Sump housing threaded

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I have a 2006 RMZ250 and done a few oik changes took it on a track for the first time & lost the sump bolt when I replaced the bolt I can only tighten to finger tight and I can still spin round and round with my fingers so I guess its the housing thats threaded is there a way to fix this without buying a new case

Thanks

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The stripped thread should be repairable by either a Helicoil or re-tapping the hole to a larger size.

 

I am not sure what thread size the RMZ250 uses for the sump drain plug but I just repaired a YZ450F this week which had the stripped it's sump thread too. The YZ450F used an M10 fine pitch thread. Rather than insert a helicoil I just tapped out the hole to the next size up which was a 7/16th UNF thread. The engine need removed for me to carry this out as Yamaha managed to place the plug behind the frame rail which ruled out access to tap it with the engine in place. Once it was removed though I was able to tap a new thread without dissasembling the engine casings. Just make sure the tap starts the new thread straight and not squint. Also grease the flutes of the tap and this will hold the cuttings as the tap cuts the new thread, remove, clean and re-grease the tap several times during the process to ensure no swarf goes inside the casings. A final check with a greased cotton bud will clean up any residual metal from the tapping process.

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The stripped thread should be repairable by either a Helicoil or re-tapping the hole to a larger size.

I am not sure what thread size the RMZ250 uses for the sump drain plug but I just repaired a YZ450F this week which had the stripped it's sump thread too. The YZ450F used an M10 fine pitch thread. Rather than insert a helicoil I just tapped out the hole to the next size up which was a 7/16th UNF thread. The engine need removed for me to carry this out as Yamaha managed to place the plug behind the frame rail which ruled out access to tap it with the engine in place. Once it was removed though I was able to tap a new thread without dissasembling the engine casings. Just make sure the tap starts the new thread straight and not squint. Also grease the flutes of the tap and this will hold the cuttings as the tap cuts the new thread, remove, clean and re-grease the tap several times during the process to ensure no swarf goes inside the casings. A final check with a greased cotton bud will clean up any residual metal from the tapping process.

Thanks for the quick reply very useful I know the bolt is a17mm spanner but I have no idea what size/type thread it is, also to helicoil the sump would I need a 17mm repair coil or would I need to tap it to a bigger size?

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Thanks for the quick reply very useful I know the bolt is a17mm spanner but I have no idea what size/type thread it is, also to helicoil the sump would I need a 17mm repair coil or would I need to tap it to a bigger size?

Just take to shop they have them and tools know how to put them in right will only take them 15mins. Allways replace copper washer when you change oil. And buy you a tourqe wrench and learn to use it.

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