Crush washer orientation question

A or B It really doesn't matter. Why would it matter ?

Jeff, I've never seen a crush washer in that shape before. Have you offered it up to the drain plug hole in the crankcase to see if it snuggles into the edges of the hole at all - in either orientation?

My basic instinct would be flat side to crankcase and cone side to the bolt, so that as the bolt is tightened, the crushing of the cone applies pressure to the flat "sealing" side of the washer. But that's not meant to be a definitive answer.

Maybe someone out there has dealt with that particular type of crush washer in the past.

Tim

(Jeff Dantzler ) scribbled:

... i love how both photos put the washer "in the shadows" :)

B) you can't crush it if you're on the low side.

B, because that's the way the old one was installed on my car when I did my first oil change, and it wasn't leaking. It's entirely possible that it doesn't matter.

What I want to know is if there is any benefit to that style vs. the more common flat copper, aluminum, or nylon washer.

-Ron

....and is it necessary to replace the crush washer each time you change oil?

RWL

flat to the boss, coned part toward the bolt head.

Yes, A Yes B, It really doesn't matter. Why WOULD it matter ? It is a seal, one side goes against a bolt head, the other side goes against (in this case) the oil pan. It is to help prevent oil from leaking out, BOTH sides have to make a good seal for it to work.

You want the crushable part to conform to the oil pan surface.

A or B becasue it doesn't matter. It is a seal, it has to seal against the bolt head AND against the oil pan.

A or B It doesn't matter. As a seal it has to seal against both the oil pan and the bolt head.

A) Flat part of crush washer against bolt "washer"

On my bikes I always have flat part to the bolt and the cone part to the sump. Why ? The conical part crushes to the sump plug hole and crushes to seal any burrs etc in the sump pan. Aliminium, Magnesium etc being softer than the bolt will distort or burr far more readily than the bolt head ever will.

HTH Jim

I can't help you with which way to orient the crush washer. Sorry.

But I'm curious as to what kind of bike? And is that a dealer supplied washer? I maintain a BMW and Ducati that use crush washers on several drain openings each and all of the crush washers are either flat aluminum or flat copper. I've never seen a cone shaped washer like that in any bike application.

Thanks to all who replied.

The bike is a Suzuki SV650 and the bolt is stock along with the dealer bought washer.

I have always put the cone down, towards the bolt such that the flat side of the crush washer faced the drain hole. The alloy around the drain is faced real pretty like and is flatter and less irregular than the bolt. There is no flange that would be complementary to the cone on either mating surface. I've never had any leaks.

I was just changing the oil yesterday and wondered why was I doing it this way. Probably because that's what the mechanic said way back when.

Just thought I'd throw it out and see what people came up with.

I suspect it would work either way because the torque applied always makes it flat on *both* sides eventually :)

Thanks.

Jeff

Makes no differnce. It won't leak as long as it's crushed...

Hear ye, here ye Jeff Dantzler doth declare:

Follow the instructions in the service manual.

Because if it's important, there will be instructions about it there.

pooder was here hoping you have a service manual

There really is no 'correct' sexual orientation. Live your life that in the manner the brings you the most happiness.

My wife doesn't agree with this philosophy.