Oil plug washer?

[SneakyDingo]

Also why it's a crime that I've seen prices as high as $6.50 for the OEM Honda washers. The mark up is insane.

 

[AZ7000']

as a rule, straight threads are never a seal, period. there either has to be a taper or a crush washer or o-ring to seal. this is universal, and one of my biggest pet peeves is seeing somebody apply teflon tape to straight threads, its one of the most ignorant things to do in any application.

the reason i use a stat o seal (or bonding washer) is that it: 1: is much easier on the threads. 2: the buna seal will always deform easier and fill in any imperfections better than an aluminum crush washer. 3: you -can- apply regular bolt torque numbers when using a bonding washer as there is a positive seat with the outer ring. 4: they are by design, reusable.

I would strongly recommend using them.

why then do aluminum crush washers still get used? cost. its a stamped ring of -slightly- softer aluminum that costs a fraction of a cent to make in mass production.

https://www.mcmaster.com/93786A200/ (or similar)

Paywall

 

[dmonkey]

The other thing that helps with forming the seal is that the metal-bonded sealing type washers are intentionally sized to be an interference fit. The M12 washer has an ID of 11.7mm at the "rubber" seal where an aluminum washer would often be 12mm. That forces it to seal against the shank, or in this case threads, of the bolt rather than just between the bolt head and mating surface. The smaller washers have a lower temperature range spec for the Buna-N seal which the oil drain plug can get close to, but I haven't melted one yet or otherwise had it fail. A nice bonus to the interference fit is that you're not going to drop the washer when you pull the bolt, it stays on there requiring some light intentional effort to pull it off or thread it off.

These are those same ones from @m in sc 's McMaster-Carr link above. Some of the Gold Wing community don't like the idea of the interference fit and will run the 1/2" ones (larger ID) on M12 drain plug bolts instead so it's not tight on the threads and they've not had issues with that. IMO may as well run the size intended to have a better seal if you're buying a special washer with the purpose of getting a good seal.

 

[m in sc]

its a mcmaster carr link, not paywal. lol.

get the right size and it wont be an issue. advance auto or any auto parts store carries them as well. they are a face seal even if it does touch the shank of the bolt. they do that to center it on the bolt. https://shop.advanceautoparts.com/p/needa-parts-metal-rubber-drain-plug-gasket-fits-1-2-m12-m12-so-365274.1/3491846-P?searchTerm=+Needa+Parts+Metal/Rubber+Drain+Plug+Gasket,+Fits+1/2,+M12,+M12+So

 

[SneakyDingo]

its a mcmaster carr link, not paywal. lol.

I think they were getting the same response I was on first click; the link sent me to a login page. I figured McMaster Carr was down for maintenance and would try again later, and it works fine right now (6:50am Pacific)