Oil Screen Crush Washer

[edclee]

Anyone have any idea of either the dimensions or the Spruce part number of the Lycoming 0-320 Oil Screen crush washer? I could measure it on my next oil change but then I would have to wait for delivery to replace the oil.
Ed

[n82rb]

AN-900-16

bob burns
RV-4 N82RB

[Vlad]

On my O-320 it's a solid copper washer.

[edclee]

[quote=n82rb;1585238]AN-900-16

bob burns
RV-4 N82RB[/QUOTE
Thanks Bob

[rv8ch]

AN900-16 MS35769-21 GASKET

https://www.aircraftspruce.com/catal...ages/an900.php

Same for my IO-360 with cold sump.

[alpinelakespilot2000]

Originally Posted by Vlad

On my O-320 it's a solid copper washer.

Yes, I've wondered if anyone just uses a regular solid washer. If both the sump surface area and the bolt are smooth, why do we have to use a crush washer here?

Getting the crush washers compressed just enough to seal, but not so tight that they leak, seems a never ending quest. I've read all the clocking directions for torque but never perfectly succeed and have to end up living with a very slow, yet persistent drip. Would love to be able to just use a solid washer!

[Stevea]

Originally Posted by alpinelakespilot2000

Yes, I've wondered if anyone just uses a regular solid washer. If both the sump surface area and the bolt are smooth, why do we have to use a crush washer here?

Getting the crush washers compressed just enough to seal, but not so tight that they leak, seems a never ending quest. I've read all the clocking directions for torque but never perfectly succeed and have to end up living with a very slow, yet persistent drip. Would love to be able to just use a solid washer!

Better yet, why not use something like this....the drain plug from my 1997 Ford Ranger:
https://www.partsgeek.com/gbproducts...-01122927.html

The o-ring under the bolt flange is contained by the flange groove and does not fall out when removed. Also, by design the o-ring crush depth is controlled by the bolt flange bottoming out on the oil pan. And best of all.....it never leaks. No replaceable gasket required (unless the o-ring were to get nicked).

Maybe the flange area under the Lyc finger screen drain plug isn't wide or thick enough for an o-ring. Haven't tried laying it out. I just ended up putting a new crush washer on last time.....as always.

As for why a crush washer is used......same reason a stock Lycosaur has paper intake manifold gaskets, cork valve cover gaskets, and a silk thread sealing the engine case halves.......it was certified in the early 1950s. Yes, there are alternatives to all of these, but still have not seen anything that replaces the crush washer on the finger screen drain plug. I suspect Vlad's solid copper gasket is an uhm, after market experimental sort of thing.

[AlexPeterson]

And don't forget to safety wire those buggers! It is alarming how instantly loose they become when being removed.

[edclee]

Originally Posted by AlexPeterson

And don't forget to safety wire those buggers! It is alarming how instantly loose they become when being removed.

Thanks for the part number. Got two ordered from Spruce. As for safety wire...always. It would ruin your whole afternoon if that thing got loose!

[rongawer]

There's a very nice Service Table of Limits from Lycoming, SSP-1776, currently revision 5. On page 2-30, there is a table within instructions for installing crush gaskets. On my IO-540, the screen plug is a 1" x 20 pitch thread plug made of aluminum. In my case, I turn the plug in until it is fully contacting the washer, then another 135º. Safety wire in place. Done.

Hopefully this takes some of the guess work out of the process.

An MS35769-21 is the right part at only 68¢ each from Spruce...solid copper gaskets in 1" ID can also be bought and will work, although the pricing is insignificant IMO and I just buy the correct part number in volume to have on hand. Either way, you can use the same installation process.

Originally Posted by Stevea

Better yet, why not use something like this....the drain plug from my 1997 Ford Ranger:
https://www.partsgeek.com/gbproducts...-01122927.html

The o-ring under the bolt flange is contained by the flange groove and does not fall out when removed. Also, by design the o-ring crush depth is controlled by the bolt flange bottoming out on the oil pan. And best of all.....it never leaks. No replaceable gasket required (unless the o-ring were to get nicked).

I agree, for the drain plug, but the OP question was regarding the oil screen plug, which a quick drain won't do the job. {you are pulling and inspecting the screen with each oil change, right? }

For the drain plug, I personally use, and recommend Stahlbus quick drain, the correct size 1/2-14