Oil, drain plug, crush rings

[5twins]

Face the open or sharp edged side out towards the drain plug. The engine or sump plate is softer alloy and those sharp edges could cut into it, grooving up the sealing surface. The drain plugs are steel and much harder.

 

[5twins]

Here's another option, solid copper ones. I got some but haven't tried them yet, but the price is certainly right, only about 50 cents each .....

http://www.ebay.com/itm/20Pcs-30mm-...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649

 

[NorazDad]

Thanks.. Makes sense.

 

[Mikey]

#AN900-19 is the proper part # and 1 3/16" is the right I.D. for our drain plugs. I don't know why Pete doesn't correct that post (or the moderators), it's very confusing and misleading.

I ordered a bunch of these last summer. Shipping is dirt cheap from this place, about a dollar, so you can get a dozen of these washers for about $10. They are slightly smaller (thinner) than the MikesXS ones but work fine, and the price is right.

If they are good enough for an airplane engine they got to be good
Been using them for a few years never a problem just put in new every oil change
Now at $1.59 per