Help with oil plug B&S 31P777

[Bange]

My level of knowledge in this equipment is very low, so some questions may seem naive, but I believe they are valid since most users are in fact ignorant and I believe that this forum exists to clarify doubts about defects, operation, exchange experiences as you and many others do so gently.
Of course, these engines are very simple, but if treated with the care and importance of a Formula 1, they should give the owner a lot more satisfaction.
I do not know, internally or for information (now I do), an original B&S filter with a bypass valve, I know that in the automotive industry there is ... but I see no problem with having an extra guarantee with a magnetic trap, like in a car.
In the event that the owner changes the filter regularly, I think that the presence of such a trap can prove the quality of the filter, show that the change must be made in less time or even that a random or manufacturing problem has occurred.
To change the filter itself, it's like the drain without the extension ... the oil runs over the chassis ... I saw a JD model with an "easy change" filter, very smart ... there is something similar for the 31P777 ?

 

[Bange]

Well ... I bought another automotive filter with the same thread as the previous one (M20), only a little bigger.
This decision was not to further spoil what was started by the previous owner.


I also opened the old filter to analyze more filings and get to know it from the inside.


I washed it with gasoline to loosen the oil and filings, then I filtered the coffee (rs) and captured the filings with the magnet.

I certainly didn't capture everything and I don't know if it's too much or too little.

In the oil filter element, not everything that shone was made of iron.


I discovered the two internal valves ...


One thing that worries me is the bypass valve spring ... it is very strong and depending on the pressure of the pump, it will not open in the event of a clog and the internal irrigation of the engine can be impaired. In cars around here, the oil pressure ranges from 20 to 70 PSI, depending on the engine, I don't know what my B&S pressure is ... would anyone know?

 

[Virgil_c]

Hey guys!
As some already know, I am repairing a Murray 42" with B&S 31P777 and one of the problems is the oil plug that came with a water valve (don't laugh).
I need to know the measures of such a plug to make an appropriate one, because here it is either very expensive or it is very difficult to get original parts.
I need the following measures:
What is the external measure of the plug thread?
How many threads per inch? I believe it is 20 ... is that correct?

Wrong valve...?
View attachment 56204
View attachment 56205

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[Bange]

Virgil_c
I live a little far from the big lawn mower market (USA), where everything that is imported is very expensive or difficult to find. Things that are simple and even cheap for Americans, are complicated and expensive for Brazilians, leaving us with the creativity for various solutions.
The problem (plug) has already been solved, leaving two questions:
1 - What is the pressure of the B&S 31P777 oil pump?
2 - How and where to place a magnetic trap to capture iron filings?
These are important questions for me, but they do not prevent the machine from working and can wait a longer time.
I saw an adapter on Amazon (Briggs & Stratton 492061 Remote Oil Filter Adapter), which can solve both issues and a third one, which is the clean filter change ... but the price to get my hands more than doubles and the solution is also to make one, and this is not difficult for me.

 

[sheenist]

Bange:A simple way to determine the size and threads per inch is to find or create a piece of round wood that is slightly tapered to start in the threaded hole. Screw into the threaded hole abaou a 1/2" then remove. The marks left on the wood will tell you the correct number of threads per inch. It will also tell you the minor dia. of the thread. I have seen this done with a small limb from a tree that had the bark removed with a pocket knife. It takes longer to read this than to do it. Good luck.
Sheenist

 

[VRR.DYNDNS>BIZ]

My level of knowledge in this equipment is very low, so some questions may seem naive, but I believe they are valid since most users are in fact ignorant and I believe that this forum exists to clarify doubts about defects, operation, exchange experiences as you and many others do so gently.
Of course, these engines are very simple, but if treated with the care and importance of a Formula 1, they should give the owner a lot more satisfaction.
I do not know, internally or for information (now I do), an original B&S filter with a bypass valve, I know that in the automotive industry there is ... but I see no problem with having an extra guarantee with a magnetic trap, like in a car.
In the event that the owner changes the filter regularly, I think that the presence of such a trap can prove the quality of the filter, show that the change must be made in less time or even that a random or manufacturing problem has occurred.
To change the filter itself, it's like the drain without the extension ... the oil runs over the chassis ... I saw a JD model with an "easy change" filter, very smart ... there is something similar for the 31P777 ?

The red circle is the location of the drain plug. Also, synthetic oil is over kill and wasted money in my opinion. Low oil casuess damage but in 50 years i HAVE ONLY SEEN 1 engine damaged from poor oil changes and that was caused by oil port pluggage.

 

[VRR.DYNDNS>BIZ]

B&S has lawn mower engines today that do not recommend oil changes over the life of the engine. I agree, as long as the level is maintained.

 

[bertsmobile1]

reported

 

[bertsmobile1]

reported

 

[Bange]

B&S has lawn mower engines today that do not recommend oil changes over the life of the engine. I agree, as long as the level is maintained.

Well, I find it strange that an internal combustion engine manufacturer does not recommend changing the oil, as it deteriorates, loses its lubricating characteristics, whether due to mileage, downtime or hours of use.
As for gearboxes, without contact with fuel and the outside environment, it is more than logical.
As for the level, regardless of the combustion engine or gearbox, it must always be inspected and topped up during its useful life...because if the volume is insufficient, lubrication is impaired and the engine's useful life is reduced.