OEM oil drain plug washer, one side is blue felt and the other bare aluminum. Which side goes towards to pan?
Toyota Oil Drain Plug Washer - Which Side?
- Thread starter SavagePatch
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I believe the blue side goes against pan. I have packet of them that are plastic and all black
Mine are blue on both sides.
Originally Posted By: Farmer
They should be blue on both sides. Aluminum in the middle.
You are right. They are blue on both sides. On one side the blue seems thicker. Do you know which side goes towards the pan?
They should be blue on both sides. Aluminum in the middle.
You are right. They are blue on both sides. On one side the blue seems thicker. Do you know which side goes towards the pan?
Originally Posted By: HerrStig
Mine are blue on both sides.
Thanks for the correction, I didn't notice that at first.
Mine are blue on both sides.
Thanks for the correction, I didn't notice that at first.
It doesn't matter I flip mine 180 degrees every OCI going on 130K on the accord. Washer looks new
Both sides are blue but one side serves as a "crush" felt that goes on the pan side. If you look at a new washer closely or scratch with your fingernail you will see the thick felt layer that gets crushed onto the pan. When you remove the drain plug the felt in the middle of the washer is uncrushed / conforms to the drain opening.
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Originally Posted By: Kibitoshin
Both sides are blue but one side serves as a "crush" felt that goes on the pan side. If you look at a new washer closely or scratch with your fingernail you will see the thick felt layer that gets crushed onto the pan. When you remove the drain plug the felt in the middle of the washer is uncrushed / conforms to the drain opening.
Thank you! Exactly what I was looking for. Excellent explanation.
Both sides are blue but one side serves as a "crush" felt that goes on the pan side. If you look at a new washer closely or scratch with your fingernail you will see the thick felt layer that gets crushed onto the pan. When you remove the drain plug the felt in the middle of the washer is uncrushed / conforms to the drain opening.
Thank you! Exactly what I was looking for. Excellent explanation.
Originally Posted By: SavagePatch
Originally Posted By: Kibitoshin
Both sides are blue but one side serves as a "crush" felt that goes on the pan side. If you look at a new washer closely or scratch with your fingernail you will see the thick felt layer that gets crushed onto the pan. When you remove the drain plug the felt in the middle of the washer is uncrushed / conforms to the drain opening.
Thank you! Exactly what I was looking for. Excellent explanation.
I've never paid attention to which side is which and I've never had a leak which leads me to believe it doesn't matter.
Originally Posted By: Kibitoshin
Both sides are blue but one side serves as a "crush" felt that goes on the pan side. If you look at a new washer closely or scratch with your fingernail you will see the thick felt layer that gets crushed onto the pan. When you remove the drain plug the felt in the middle of the washer is uncrushed / conforms to the drain opening.
Thank you! Exactly what I was looking for. Excellent explanation.
I've never paid attention to which side is which and I've never had a leak which leads me to believe it doesn't matter.
As far as I know both sides look identical with respect to the felt..although i notice one side in the middle sticks up more so i put it that way..truly i dont think thrre is a right or wrong side on the OEM washers.
Originally Posted By: Kibitoshin
Both sides are blue but one side serves as a "crush" felt that goes on the pan side. If you look at a new washer closely or scratch with your fingernail you will see the thick felt layer that gets crushed onto the pan. When you remove the drain plug the felt in the middle of the washer is uncrushed / conforms to the drain opening.
EITHER side of the washer will conform to the drain hole. Even washers that are all-aluminum and are identical on both sides will conform to the drain hole.
It does not matter which side goes against the pan. Both pan and bolt sealing-surfaces are identical and both need to be sealed identically in order for the join to be oil-tight.
The join will leak if one side fails to seal completely, and a leak will occur regardless of which side it was that failed to seal.
Both sides are blue but one side serves as a "crush" felt that goes on the pan side. If you look at a new washer closely or scratch with your fingernail you will see the thick felt layer that gets crushed onto the pan. When you remove the drain plug the felt in the middle of the washer is uncrushed / conforms to the drain opening.
EITHER side of the washer will conform to the drain hole. Even washers that are all-aluminum and are identical on both sides will conform to the drain hole.
It does not matter which side goes against the pan. Both pan and bolt sealing-surfaces are identical and both need to be sealed identically in order for the join to be oil-tight.
The join will leak if one side fails to seal completely, and a leak will occur regardless of which side it was that failed to seal.
Generally the flat side of the washer goes to the pan and the rounded edge side to the bolt. The reason they claim is that when these things are cut out by the press the bottom is pressed flatter while the top is slightly rounded.
The flatter side of the washer goes to the flatter or machined surface which would be the pan, brake caliper or other housing while the slightly rounded part gets crushed by the bolt. The bolt edges are flats and don't require sealing in that area.
Personally I don't think it makes a lick of difference, if it did they would use a ground on both sides washer like they do inside some transmission, diffs, etc.
The flatter side of the washer goes to the flatter or machined surface which would be the pan, brake caliper or other housing while the slightly rounded part gets crushed by the bolt. The bolt edges are flats and don't require sealing in that area.
Personally I don't think it makes a lick of difference, if it did they would use a ground on both sides washer like they do inside some transmission, diffs, etc.
Originally Posted By: Trav
I don't think it makes a lick of difference
Trav, consider the construction of the joint. It CANNOT make the slightest whit of a difference which way the washer goes.
I'll post a sketch later today showing why it's impossible for the washer-direction to make a difference.
I don't think it makes a lick of difference
Trav, consider the construction of the joint. It CANNOT make the slightest whit of a difference which way the washer goes.
I'll post a sketch later today showing why it's impossible for the washer-direction to make a difference.
I don't think it makes any difference either, like I said if it did they would parallel grind both faces but that's what was published many years ago when I was in school.
I've had a Fumoto Valve on my Toyota Tacoma since around 2003, so I have no idea.
I've never had a leak and have also had one in my Hyundai since 2005. Fumoto valves and whatever washer they come with appear to REALLY last.
I've never had a leak and have also had one in my Hyundai since 2005. Fumoto valves and whatever washer they come with appear to REALLY last.
Originally Posted By: Tegger
I'll post a sketch later today showing why it's impossible for the washer-direction to make a difference.
And here it is. Sealing on both sides must be perfect, otherwise there will be a leak. That the washer is asymmetrical is of no importance to its function as a sealing device; you can install it either way.
If Toyota thought direction made a difference with the washer as it is now, they would have changed the washer to be symmetrical, with equal padding on both sides.
Remember that Honda washers have no padding at all. They are plain aluminum right through, and not even particularly well-finished, at that. Honda is obviously relying on the "crush" characteristics of the washer to cancel-out any surface defects.
I'll post a sketch later today showing why it's impossible for the washer-direction to make a difference.
And here it is. Sealing on both sides must be perfect, otherwise there will be a leak. That the washer is asymmetrical is of no importance to its function as a sealing device; you can install it either way.
If Toyota thought direction made a difference with the washer as it is now, they would have changed the washer to be symmetrical, with equal padding on both sides.
Remember that Honda washers have no padding at all. They are plain aluminum right through, and not even particularly well-finished, at that. Honda is obviously relying on the "crush" characteristics of the washer to cancel-out any surface defects.
Yes, as usual people are running away with their imaginations. Today's mortal danger to engine longevity seems to be drain plug washer direction. Tomorrow it might be metal shavings coming from the dipstick rubbing against the tube
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