Help with oil plug B&S 31P777

Bange

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Evolution 2...

Turned and ready parts.
Peças prontas e borracha de teste.jpg

Connected parts.
Peça pronta 2.jpg
Note: soft washer is missing and exchange EVA rubber for another nitrile.
 
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VRR.DYNDNS>BIZ

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I don't mean to sound condescending but i think you're over thinking it some....go to your hardware store. Buy a 3/8 NPT tube, male thread on both ends and buy a cap or valve to fit on one end.
Teflonsealing tape on both ends. Install it. You're done.
Or you can call Briggs And Stratton and ask them what size thread the 31p777 engine sump drain plug is.
Perfect answer. Believe it.
 

Bange

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I totally agree ... but when the option is too far away or too expensive, there are other possible and fully acceptable options ... not for everything, of course!
 

Bange

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You know something is good, but can it improve?
So it is...

Para não perder a tampa 2.jpg
Para não perder a tampa 1.jpg
Detalhe 1.jpg
Detalhe 2.jpg
 

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Bange

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A small modification ...
Nitrile rubber is expensive and would still have to be adapted ... but there is an almost inexhaustible and free source on the floor of car workshops.
It is an O-ring of the fuel injector nozzles.
Then...

Modificação 1.jpg
Modificação 2.jpg
O-rings.jpg

I tried to make an aluminum washer, it didn't look good ... so I made it out of brass too.
Arruela de latão.jpg

With a good grip I don't think it would leak, but I added teflon tape as a guarantee.
Com arruela.jpg

I am concerned with vibration ... as the lid will not need a tightening tool, only the hand, can it loosen and leak? It will be seen during the first hours of use ...
This is for those who open engines: is it worth making a magnetic trap to retain iron filings present in the oil?
 

Rivets

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You’ve stuck more time than 99% of us here and you’re having fun. Go for it, what do you have to lose. Only thing I would question, do you think there are that many iron filings in an aluminum block engine? Aren’t most of the bearings/bushings aluminum?
 

Bange

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Really, spending my time on the things I like is fun ... boring is not having the materials on hand and taking a while to get them, doing is another fun.
Just as there was no magnetic plug in my car, after putting it on I was amazed at what was circulating and I imagine the harm it does ...
After analyzing the oil that came out of my B&S (I don't know how long it was there), I noticed shiny particles, in fact I don't know if iron, bronze or aluminum, hence the question) that come out with the friction of some parts and I find it interesting to apply the same reasoning as for my car.
You commented something interesting ... if they are not made of iron or steel, it will not do any good ... as I have not yet discarded the oil, I will pass a magnet on it and see the result.
 

Born2Mow

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....go to your hardware store. Buy a 3/8 NPT tube, male thread on both ends and buy a cap or valve to fit on one end. Teflon sealing tape on both ends. Install it. You're done.
Exactly. AND the short pipe extension will mean that oil drains into the pan, and not all over the mower frame.
 
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Bange

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Analyzing the oil ...
Due to the lack of knowledge of a standard procedure (which can even be centrifuging and not magnetic), I adopted a very simple one that can be seen and understood by the photos and video below, remembering only that the oil was not at the working temperature and that the debris in greater volume and size must be retained in the oil filter.

This was the initial oil collection pot.
F1.jpg
Attaching a magnet to the bottom of the pot
F2.jpg
F3.jpg
F4.jpg
Iron filings ...
F5.jpg
F6.jpg
Wrapping the magnet in a PVC film and immersing it in the oil.
F7.jpg
F8.jpg
Iron particles captured by the magnet.
F9.jpg

It was not in my plans to replace the oil filter now, however, after the presence of iron filings was confirmed, I decided to remove the oil from its interior ... and I found another problem ... the engine thread is 3/8 inch and the filter thread is 1.5mm, sacrificing the motor thread.

F10.jpg

Well, the evaluation was preliminary and I do not consider it conclusive, but it only served to confirm the presence of iron filings, which certainly passed through the filter, if they are harmful in size or volume, I can say nothing, but logic tells me that it is.
I will think of a way to set a trap, but this will take a lot more time.
 

bertsmobile1

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I really wish people with little understanding of the lubrication system would refrain from posting simplistic "experiments " on the web.
All mower oil filters have a bypass valve so when the filter is clogged the oil bypasses the filter so the engine does not seize .
If you can see it then it CAN NOT PASS THROUGH THE FILTER PAPER unless the paper is damaged.
Next there are a lot of things that are ferro magnetic, like gravel dust for one.
Oil filters on mowers get changed on an hours of operation or lapsed time basis, not on a full yet basis.
And yes the oil filter thread can be NPT or Metric
However the thread cout & profiles are close enough for it not to matter.
Remember these are no formula 1 engines running at 11 tenths of their design limits
Mower engines , now that Honda have exited the market are the cheapest easiest to make lowest output engines it is possible to manufacture & sell.
They are really not much more advanced technically that they were in 1920
 
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