oil filter

but it's primary purpose is to regulate the oil pressure within the design limits of the oil pump and the filter with the engine operating normally. It is not intended to save the engine in the event of a catastrophic internal failure that causes excessive amounts of junk to clog up the filter.

You must be an engineer.....can't think out of the box....and get a spell checker...

Hello Pamcopete,

This is just not right! Its primary purpose is not to regulate the oil pressure at any time!

And it is intended to save the engine, not after a catastrophic internal failure that causes exessive amounts of junk that clog up the filter, that's too late anyway, but in case of a clogged filter due to a too late oil change. We treat our XS classics as our babies now, but there were (an maybe still are) people who only check the oil level once a year.

And yes, I em u Dutch inganeer and I neet a spall shecker:shrug:

Kind regards and let's be nice,

Hein
 
hein,

You would not experience a clogged oil filter just because you were late changing the oil. There would have to be an accumulation of foreign material to clog the filter. When the bypass opens, the "dirty" oil is then allowed passage into the engine where it can cause damage.

Predictable failures, such as the disintegration of the timing chain guide, can create a mass of debris in the oil, which gets past the sump filter because all sump filters have a hole in them. The bypass opens and lets this junk into the more delicate parts of the engine, or it simply causes oil passage blockage which would require you to tear down the engine to cure.

By eliminating the by pass valve, you eliminate this possibility, but it is essential that you then install an oil pressure gage so you can monitor the pressure in the absence of the bypass valve.

The early XS650's had the bypass installed in the oil pump itself which precluded allowing the dirty oil to re enter the engine. A much better arrangement and one that matches my opinion on both the purpose and function of the bypass valve. I presume that Yamaha in it's wisdom eliminated the valve on the pump and moved it to the oil screen as a cost saving measure.

Having the oil pressure bypass installed as part of the pump, venting to the crankcase, made this arrangement more of a true pressure regulator because it was vented to essentially a zero pressure area, whereas the current arrangement vents to the engine oil galley, which would still produce some back pressure, limiting the effectiveness of the by pass to regulate the pressure below the inherent pressure in the oil galley.

Normally, one expects an engineer to be detailed in their assertions. So, when you say that:

"This is just not right! Its primary purpose is not to regulate the oil pressure at any time!"

It sounds more like an opinion rather than a factual statement that can be backed up by perhaps some numbers, like

1. What is the maximum differential pressure that the oil screen can withstand without failing?
2. What is the maximum pressure that the oil pump can produce before damage occurs?
3. What is the maximum negative pressure that the sump screen can withstand before it develops a hole?
4. What, in your opinion, is the main cause of a hole developing in the sump screen if it is not excessive low pressure and flow during the cold engine operation?
5. If there is a number to answer all of the above, then how do you regulate the pressure so those numbers are not exceeded?
6. Why did Yamaha initially build the oil pressure relief valve into the oil pump and not the oil screen?
7. Why did Yamaha move the valve to the screen?

I don't know if you have a spell checker or not, but a good and FREE one is available from: http://www.iespell.com/

And, welcome to the club!
 
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hein,

You would not experience a clogged oil filter just because you were late changing the oil. There would have to be an accumulation of foreign material to clog the filter. When the bypass opens, the "dirty" oil is then allowed passage into the engine where it can cause damage.

Predictable failures, such as the disintegration of the timing chain guide, can create a mass of debris in the oil, which gets past the sump filter because all sump filters have a hole in them. The bypass opens and lets this junk into the more delicate parts of the engine, or it simply causes oil passage blockage which would require you to tear down the engine to cure.

By eliminating the by pass valve, you eliminate this possibility, but it is essential that you then install an oil pressure gage so you can monitor the pressure in the absence of the bypass valve.

The early XS650's had the bypass installed in the oil pump itself which precluded allowing the dirty oil to re enter the engine. A much better arrangement and one that matches my opinion on both the purpose and function of the bypass valve. I presume that Yamaha in it's wisdom eliminated the valve on the pump and moved it to the oil screen as a cost saving measure.

Having the oil pressure bypass installed as part of the pump, venting to the crankcase, made this arrangement more of a true pressure regulator because it was vented to essentially a zero pressure area, whereas the current arrangement vents to the engine oil galley, which would still produce some back pressure, limiting the effectiveness of the by pass to regulate the pressure below the inherent pressure in the oil galley.

Normally, one expects an engineer to be detailed in their assertions. So, when you say that:

"This is just not right! Its primary purpose is not to regulate the oil pressure at any time!"

It sounds more like an opinion rather than a factual statement that can be backed up by perhaps some numbers, like

1. What is the maximum differential pressure that the oil screen can withstand without failing?
More than 14 psi. These oil screens are not known to fail often
2. What is the maximum pressure that the oil pump can produce before damage occurs?
Damage to what? If the filter is clogged and there is no way the oil can escape the pump wil brake. I do not know the maximum pressure the pump can make
3. What is the maximum negative pressure that the sump screen can withstand before it develops a hole?
When you mean differential pressure, I think not much. IMHO the sumpscreen does not break because of the pressure difference, but by the strong oil flow near the outlet of the filter
4. What, in your opinion, is the main cause of a hole developing in the sump screen if it is not excessive low pressure and flow during the cold engine operation?
See 4
5. If there is a number to answer all of the above, then how do you regulate the pressure so those numbers are not exceeded?
See 6 and 7
6. Why did Yamaha initially build the oil pressure relief valve into the oil pump and not the oil screen?
Indeed Yamaha built a PRV on the early XS, but that was not to replace the savety valve. They were both there! And again: they do not have the same function. A PRV limits the pressure to a certain maximum, the safety valve is only there to save the engine in case of a clogged filter. Normally it will not open in the entire lifetime of the bike.
http://i957.photobucket.com/albums/ae54/inxs-de/oil pump/P3220002.jpg http://i957.photobucket.com/albums/ae54/inxs-de/oil pump/P3220002.jpg

7. Why did Yamaha move the valve to the screen?
They did not move it, they removed it. To be honest: I think that was not a good move!
I don't know if you have a spell checker or not, but a good and FREE one is available from: http://www.iespell.com/


And, welcome to the club!

Kind regards, Hein
 
Hein,

Well, my confidence is restored, to a certain degree, but there are some incongruities in your answers:

2. What is the maximum pressure that the oil pump can produce before damage occurs?
Damage to what? If the filter is clogged and there is no way the oil can escape the pump will brake. I do not know the maximum pressure the pump can make

You ask the question "damage to what" and then you provide the answer. The oil pump will break.

3. What is the maximum negative pressure that the sump screen can withstand before it develops a hole?
When you mean differential pressure, I think not much. IMHO the sumpscreen does not break because of the pressure difference, but by the strong oil flow near the outlet of the filter

Isn't the mark of a strong flow a difference in pressure? How can you have a strong flow without a pressure differential?

A PRV limits the pressure to a certain maximum, the safety valve is only there to save the engine in case of a clogged filter. Normally it will not open in the entire lifetime of the bike.


I'm still confused as to how allowing contaminated oil into the engine can "save the engine". If the filter is clogged, then there are contaminants in the oil.

Anyway, Hein, thanks for your time and expertise.
 
- XS-XS1F...early configuration
P3220001.jpg


- XS1F on...later configuration
P3220002.jpg
 
Hi Pete,

This is the text from the original manual for the early XS with PRV on the oil pump:

'the oil pump is fitted with a bypass valve-check ball and spring-that permits the oil from the pump to be redirected back to the oil reservoir in case of excessive pressure in the delivery passages...the cover has a drilled hole that leads to a pressure relief check ball. If too much pressure develops the check ball releases oil back into the crankcase'
and:

'the filter is fitted with a bypass. If the filter is plugged, oil is forced through a spring-loaded ball type check valve in the locking bolt and into the engine delivery passage. In this manner, oil delivery to the engine will not be stopped by a clogged filter.'

Kind regards, Hein

P.S. It seems I posted the same picture twice. Inxs posted the correct two pictures
 
""""""'the filter is fitted with a bypass. If the filter is plugged, oil is forced through a spring-loaded ball type check valve in the locking bolt and into the engine delivery passage. In this manner, oil delivery to the engine will not be stopped by a clogged filter.'""""""""""


Hein..........that was always my understanding of the reason for the built in filter bypass............dirty would be favorable to no oil at all...........

xsjohn
 
Hein,

Yes, we all know how the bypass valve works. But, you have to ask yourself....is feeding contaminated oil back into the engine a good thing? In other words, you have to look at what the Yamaha engineers did or said and then form your own judgment.

Just ask yourself the basics:

1. Why is the oil filter clogged?
Answer: Junk in the oil.
2. Is there still junk in the oil?
Answer: yes.
3. Is it a good idea to allow this junk into the engine?
Answer: Well, Yamaha says it's a good idea.
4. Well, I don't think so. So I'm going to eliminate the bypass valve and install an oil pressure gage so I can see when there is a problem and shut down the engine.

That 4th one is called "Critical thinking". It means that you do not just take someones word for something. You apply some thinking of your own and perhaps arrive at a different answer.

That's what I meant earlier when I suggested that you raise your thinking to another level. I wasn't being rude. I was just challenging you to think for yourself rather than believe what you had read from Yamaha or others.
 
Yea ...for people that stay on top of their engines that might be a good idea....I would run it without a bypass.......but Yamaha was surely also considering of the worst case scenero.......

xsjohn
 
And we come full circle, the best form of defence is an effective & trustworthy pre screen filter, then crud should never find it's way into the pump or filter!
 
yamaman,

Well, that's called the sump filter, but it has a hole in it, unless you manage the pressure and keep the revs down til the engine is completely warmed up.
 
Well that's common since........since most of the wear occurs on startup and cold engines............

Wear on real hot engines too........... :laugh:

xsjohn
 
Exactly Pete, and that's what this mainly thread is about, alternatives to the standard sump screen. A problem that time & time again rears its head.

I guess it's ignored by so many so often because it's hidden inside the engine. With a spin on cartridge, people might not be so reluctant to change it.

The fact that you & some others manage yours quite well is great. We all know that not all are as careful as your good self!

Also interested to know the service life of Hein's filter set up?????
 
Hein, Pete, if i may:

Yes, we all know how the bypass valve works. But, you have to ask yourself....is feeding contaminated oil back into the engine a good thing?
This seems to be the conflict point between you.

Pete, you believe that it's better to starve the engine of any lubrication, rather than have dirty lubrication.

Hein, you believe that it's better to have dirty lubrication, rather than starve the engine of lubrication.

I don't see any way that you guys are going to come to an understanding given that these are significantly polar points of view. Agreeing to disagree seems to be your only recourse.

Having said that, now i'll fan the flames. <sigh>

In other words, you have to look at what the Yamaha engineers did or said and then form your own judgment.

Just ask yourself the basics:

1. Why is the oil filter clogged?
Answer: Junk in the oil.
2. Is there still junk in the oil?
Answer: yes.
3. Is it a good idea to allow this junk into the engine?
Answer: Well, Yamaha says it's a good idea.
First of all, i highly doubt Yamaha would call this a good idea. They would rather you do your regular maintenance, and clean your filters. However, if you're going to not do that, they would rather the engine have *some* lubrication.

Secondly, the raw amount of "junk" in the oil to clog a filter would have to be... I can't think of a hyperbole large enough. I'd love to hear anyone's story about this actually happening.

Thirdly, that bypass is unlikely to allow anything through that your screen normally wouldn't anyway.

4. Well, I don't think so. So I'm going to eliminate the bypass valve and install an oil pressure gage so I can see when there is a problem and shut down the engine.

That 4th one is called "Critical thinking". It means that you do not just take someones word for something. You apply some thinking of your own and perhaps arrive at a different answer.

That's what I meant earlier when I suggested that you raise your thinking to another level. I wasn't being rude. I was just challenging you to think for yourself rather than believe what you had read from Yamaha or others.
Pete, with respect, i think this may be another "over the top" kind of project (like the headlight going out in neutral) for you to address a problem that doesn't actually exist. That's just my opinion.

And, for the record, i agree with Hein. Even *with* an oil pressure gauge, i would still believe the bypass to be a good thing.
 
Swore I wasn't getting this but here I am.......

My only concern about paper filters is what the Wix engineer told me....15 to 20 percent restriction (with 30 weight oil)......worried about that whien I did it 6 years ago or so.....2 paper filters...?..I would design the sump with a more porous screen type thing.............

I glued my original up 65 thou ago where it was collapsed and it's still in there and good.........around the edges too....... And use a paper on the high side.....

You won't like hearing this........the paper on the high side has been in there 5 years...40 thousand maybe...the outside diameter is bigger on the replacements I got so I just clean it in gas holding the rubber flap open with a stick.....:laugh:...after this discussion I will find a new one...........:eek:

xsjohn
 
Well, we have a dilemma. The sump screen fails because it does not have a bypass valve. But, Yamaha did not provide a bypass valve for the sump screen, because they reasoned that it provides the ultimate protection for the upstream pump and side cover screen, so the purpose of the side screen bypass valve must be something other than protecting the engine in the event of a blockage, because a blockage can't occur in the side cover screen because the sump filter prevents that from happening, unless Yamaha knew in advance that the sump screen would fail, but if they knew that the sump screen would fail, allowing junk to migrate to the side cover screen, then they just ran out of ideas when they said it's there to protect the engine in the event of a side cover screen blockage.....Okay??
 
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sundie,

"Pete, you believe that it's better to starve the engine of any lubrication, rather than have dirty lubrication."

Not true. I would shut the engine down if I saw the oil pressure rising (or falling, for that matter) either indication could mean imminent oil starvation.

So, I do not believe in either starving the engine of oil or allowing dirty oil to circulate in the engine. You obviously think that it is OK to allow dirty engine oil to circulate in the engine, or, lacking an oil pressure gage, allow the engine to continue running with no oil in the engine.

We tend to think that this hypothetical condition will just last until we get home, so maybe not much damage done, but in fact a dirty oil condition or low oil pressure condition can go for quite some time. Certainly long enough to damage the engine.
 
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