Possible MOP oil line cleaning method?
06-04-2012, 03:29 PM
#76
I understand that, but I would feel much more comfortable paying someone to set it right, someone that has done it before many times. Why spend +$300 only to change the omp rates when I can increase oil flow for free? Just because it is not high tech, does not mean it can not work. And I never said I couldn't screw it up. I just posted my ideas, how I did it, and my results. If anyone is following what I did they did it on their own free will, just like I did.
If you want to increase OMP rates do it with a tuner...either the Cobb or another type of reflash...otherwise you are making things worse
06-04-2012, 03:51 PM
#77
If you are using vac to pull oil out of the lines...it will just cause them to empty...and when the pump is trying to inject more oil when it needs it it will have to fill the lines first before any comes out....this is a BAD idea...DON't do this MOD...it is really stupid You are really sucking oil out when you don't need it...and not getting it properly when you do
Where does this air come from?
Why is oil consumption increased if air is filling the lines?
06-04-2012, 03:57 PM
#78
The OMP injects oil....with a positive displacement pump...so the oil will go in because it is basically non-compressible...
The rate of oil flow is determined by how the pump is commanded by the ECU to pump.....and decel is not a time that the ECU says it needs lots of oil
If you are using vac to pull oil out of the lines...it will just cause them to empty...and when the pump is trying to inject more oil when it needs it it will have to fill the lines first before any comes out....this is a BAD idea...DON't do this MOD...it is really stupid You are really sucking oil out when you don't need it...and not getting it properly when you do
If the only thing governing oil flow rates into the engine is the OMP, there there should be no way for the *average* consumption to increase by restricting the vent/vacuum line.
Both considerations imply that the OMP is not a perfect displacement pump. It either leaks through when presented with low pressure on the output side, or passes more oil through as it cycles.
06-04-2012, 04:12 PM
#79
This is in contrast, if I remember it correctly, to the oil metering on my 1978 RX-4 where the oil supply was from a lever-actuated pump and overall flow volume governed mostly by rpm. (Though there was a screw that could vary the pump stroke in a fixed way.) The "downside" was a puff of smoke here and there, plus oil higher oil consumption, both likely to be an emission problem these days. The upside was a very durable and reliable engine.
06-04-2012, 04:23 PM
#80
Registered
- On the German RX-8 forum all users of the restrictor (including myself) report increased oil consumption via the OMP; depending on the inner diameter..........
- Mazda itself reports in a TSB about increased oil consumption due to the mounting of a wrong intake tube with only 2 in stead of 3 vacuum connections; the 3rd beeing the vac connection to the OMP injectors..........
06-04-2012, 06:22 PM
#81
And unless the pump is pumping it at the correct times...more oil is not a good thing....You would be better off pre-mixing that doing this
06-04-2012, 06:25 PM
#82
If the only thing governing oil flow rates into the engine is the OMP, there there should be no way for the *average* consumption to increase by restricting the vent/vacuum line.
Both considerations imply that the OMP is not a perfect displacement pump. It either leaks through when presented with low pressure on the output side, or passes more oil through as it cycles.
Both considerations imply that the OMP is not a perfect displacement pump. It either leaks through when presented with low pressure on the output side, or passes more oil through as it cycles.
And if the engine is under Vac..you don't need the extra oil usually...so what is the use? Oil consumption for consumption sake is not useful
06-05-2012, 08:26 AM
#84
Ok so everyone here has their own opinion on whatever.
My car spends the majority of it's life below 6krpms, so I want to increase oil consumption in that rpm range.
Like I said before this engine is all but dead, so I'm not going to reply anymore to people saying to stop with out some type of proof that this is harmful (Sorry I need more proof than your word, no offense, please). Honestly this thread isn't even about what everyone is arguing over. This thread is about how I cleaned the lines out... Which I did for 8 dollars, some help and basic tools. At the 91k mile compression test, I was told to expect anywhere from 10k to 40k miles out of this engine, I'm currently at 15k mark. And sure, I'll never really know if this helped or not, there is 47k miles on this engine I can not account for. But the longer the motor last, the better in my opinion. I'm already financially ready for the next motor, so all this bitching kinda means nothing to me, let me learn and post my results.
-Shawn
My car spends the majority of it's life below 6krpms, so I want to increase oil consumption in that rpm range.
Like I said before this engine is all but dead, so I'm not going to reply anymore to people saying to stop with out some type of proof that this is harmful (Sorry I need more proof than your word, no offense, please). Honestly this thread isn't even about what everyone is arguing over. This thread is about how I cleaned the lines out... Which I did for 8 dollars, some help and basic tools. At the 91k mile compression test, I was told to expect anywhere from 10k to 40k miles out of this engine, I'm currently at 15k mark. And sure, I'll never really know if this helped or not, there is 47k miles on this engine I can not account for. But the longer the motor last, the better in my opinion. I'm already financially ready for the next motor, so all this bitching kinda means nothing to me, let me learn and post my results.
-Shawn
06-13-2012, 03:20 PM
#86
I just lost a motor recently. It was preceded by a reduction in oil consumption. I, in my ignorance, did not recognize this as an indicator of problems. I found the same dirty, sludgey oil in the OMP where the banjo bolts connect to it. I also found that some of the lines appeared to be clogged as they wouldn't readily pass compressed air. I also found that two of the injector nozzles wouldn't pass the test put forth in the manual (apply vacuum to them and see if it holds.) I assumed that this meant they wouldn't pass any oil but in light of the information in this thread I'm no longer convinced of that. I thought they were seeing vacuum through that hose but, as Team pointed out, the hose connects to a part of the system that sees near ambient pressure all the time. I don't have enough miles on this engine (which appears to be the third one in 90,000 miles as best I can determine) to be able to tell if I am consuming oil at the proper (which is what?) rate yet, so I am doing everyone's go-to safety precaution and premixing.
In other news, I took apart the OMP and discovered something interesting. It isn't a pump. There are no mechanical bits inside that thing that are capable of moving any oil by pumping. What it is doing is "admitting" oil, fed to it by the engine oil pump, to pass into the external oil injector supply lines in a variable manner. Variable depending on RPM by way of a shaft-driven gear spinning two barrels with holes in them at some speed directly proportional to and much lower (like way lower as it's a worm gear) than eccentric shaft speed. The other way it varies is by the position of two needle valve-style plungers, the positions of which are controlled by the stepper motor, under direction from the ECU.
The reason I decided to post the second part is to partly clarify the effect of plugging that main air line. Someone suggested that increasing the vacuum seen by the nozzles at the combustion chamber by plugging the line would only suck the oil from the lines and cause a delay in their being refilled by the OMP on the assumption that the OMP was a positive displacement device. Since the pump is actually only a (rather complicated) variable restriction, increasing the average pressure differential across the nozzles by plugging or restricting that line WILL actually increase the oil allowed to flow to the injectors.
As to the wisdom of this, I would say that at the track it is a good idea. It would allow a buildup of oil during off throttle conditions (relatively rare on the track compared to the street), which would prepare the engine for it's next blast to high RPM with a little extra apex seal lubrication. Allowing the ECU to have full control means that the oil will be admitted in "response" to the high load/RPM condition, which will result in some sort of short delay between when the apex seals need the oil and when they get it. However, in normal driving where the low load condition is present the vast majority of the time, I think that the benefit would be much less and would lead to an increase in seal lubrication that is mostly unnecessary.
As usual, after having written it, I feel like this post is going to get me flamed but this time I'm not going to delete it. I'm actually going to post it and see what happens, lol.
In other news, I took apart the OMP and discovered something interesting. It isn't a pump. There are no mechanical bits inside that thing that are capable of moving any oil by pumping. What it is doing is "admitting" oil, fed to it by the engine oil pump, to pass into the external oil injector supply lines in a variable manner. Variable depending on RPM by way of a shaft-driven gear spinning two barrels with holes in them at some speed directly proportional to and much lower (like way lower as it's a worm gear) than eccentric shaft speed. The other way it varies is by the position of two needle valve-style plungers, the positions of which are controlled by the stepper motor, under direction from the ECU.
The reason I decided to post the second part is to partly clarify the effect of plugging that main air line. Someone suggested that increasing the vacuum seen by the nozzles at the combustion chamber by plugging the line would only suck the oil from the lines and cause a delay in their being refilled by the OMP on the assumption that the OMP was a positive displacement device. Since the pump is actually only a (rather complicated) variable restriction, increasing the average pressure differential across the nozzles by plugging or restricting that line WILL actually increase the oil allowed to flow to the injectors.
As to the wisdom of this, I would say that at the track it is a good idea. It would allow a buildup of oil during off throttle conditions (relatively rare on the track compared to the street), which would prepare the engine for it's next blast to high RPM with a little extra apex seal lubrication. Allowing the ECU to have full control means that the oil will be admitted in "response" to the high load/RPM condition, which will result in some sort of short delay between when the apex seals need the oil and when they get it. However, in normal driving where the low load condition is present the vast majority of the time, I think that the benefit would be much less and would lead to an increase in seal lubrication that is mostly unnecessary.
As usual, after having written it, I feel like this post is going to get me flamed but this time I'm not going to delete it. I'm actually going to post it and see what happens, lol.
06-13-2012, 05:44 PM
#88
SARX Legend
iTrader: (46)
I just lost a motor recently. It was preceded by a reduction in oil consumption. I, in my ignorance, did not recognize this as an indicator of problems. I found the same dirty, sludgey oil in the OMP where the banjo bolts connect to it. I also found that some of the lines appeared to be clogged as they wouldn't readily pass compressed air. I also found that two of the injector nozzles wouldn't pass the test put forth in the manual (apply vacuum to them and see if it holds.) I assumed that this meant they wouldn't pass any oil but in light of the information in this thread I'm no longer convinced of that. I thought they were seeing vacuum through that hose but, as Team pointed out, the hose connects to a part of the system that sees near ambient pressure all the time. I don't have enough miles on this engine (which appears to be the third one in 90,000 miles as best I can determine) to be able to tell if I am consuming oil at the proper (which is what?) rate yet, so I am doing everyone's go-to safety precaution and premixing.
In other news, I took apart the OMP and discovered something interesting. It isn't a pump. There are no mechanical bits inside that thing that are capable of moving any oil by pumping. What it is doing is "admitting" oil, fed to it by the engine oil pump, to pass into the external oil injector supply lines in a variable manner. Variable depending on RPM by way of a shaft-driven gear spinning two barrels with holes in them at some speed directly proportional to and much lower (like way lower as it's a worm gear) than eccentric shaft speed. The other way it varies is by the position of two needle valve-style plungers, the positions of which are controlled by the stepper motor, under direction from the ECU.
The reason I decided to post the second part is to partly clarify the effect of plugging that main air line. Someone suggested that increasing the vacuum seen by the nozzles at the combustion chamber by plugging the line would only suck the oil from the lines and cause a delay in their being refilled by the OMP on the assumption that the OMP was a positive displacement device. Since the pump is actually only a (rather complicated) variable restriction, increasing the average pressure differential across the nozzles by plugging or restricting that line WILL actually increase the oil allowed to flow to the injectors.
As to the wisdom of this, I would say that at the track it is a good idea. It would allow a buildup of oil during off throttle conditions (relatively rare on the track compared to the street), which would prepare the engine for it's next blast to high RPM with a little extra apex seal lubrication. Allowing the ECU to have full control means that the oil will be admitted in "response" to the high load/RPM condition, which will result in some sort of short delay between when the apex seals need the oil and when they get it. However, in normal driving where the low load condition is present the vast majority of the time, I think that the benefit would be much less and would lead to an increase in seal lubrication that is mostly unnecessary.
As usual, after having written it, I feel like this post is going to get me flamed but this time I'm not going to delete it. I'm actually going to post it and see what happens, lol.
In other news, I took apart the OMP and discovered something interesting. It isn't a pump. There are no mechanical bits inside that thing that are capable of moving any oil by pumping. What it is doing is "admitting" oil, fed to it by the engine oil pump, to pass into the external oil injector supply lines in a variable manner. Variable depending on RPM by way of a shaft-driven gear spinning two barrels with holes in them at some speed directly proportional to and much lower (like way lower as it's a worm gear) than eccentric shaft speed. The other way it varies is by the position of two needle valve-style plungers, the positions of which are controlled by the stepper motor, under direction from the ECU.
The reason I decided to post the second part is to partly clarify the effect of plugging that main air line. Someone suggested that increasing the vacuum seen by the nozzles at the combustion chamber by plugging the line would only suck the oil from the lines and cause a delay in their being refilled by the OMP on the assumption that the OMP was a positive displacement device. Since the pump is actually only a (rather complicated) variable restriction, increasing the average pressure differential across the nozzles by plugging or restricting that line WILL actually increase the oil allowed to flow to the injectors.
As to the wisdom of this, I would say that at the track it is a good idea. It would allow a buildup of oil during off throttle conditions (relatively rare on the track compared to the street), which would prepare the engine for it's next blast to high RPM with a little extra apex seal lubrication. Allowing the ECU to have full control means that the oil will be admitted in "response" to the high load/RPM condition, which will result in some sort of short delay between when the apex seals need the oil and when they get it. However, in normal driving where the low load condition is present the vast majority of the time, I think that the benefit would be much less and would lead to an increase in seal lubrication that is mostly unnecessary.
As usual, after having written it, I feel like this post is going to get me flamed but this time I'm not going to delete it. I'm actually going to post it and see what happens, lol.
https://www.rx8club.com/showthread.p...&highlight=omp
06-14-2012, 01:43 AM
#89
Yep, still not a pump.
If you refer to the thread that 9k linked to you will see the pump disassembled. It doesn't have any moving parts which are capable of displacing any oil or creating pressure of any kind. All it has the ability to do is take oil supplied by the engine oil pump and meter it through orifices in a pair of rotating cylindrical valve thingeys to a varying degree determined by the positions of the two spring loaded needle valves, whose positions are determined by the stepper motor.
EDIT*** Actually the cylindrical rotating barrel valve thingeys aren't really visible in the pictures in that thread. They are still installed in the OMP so you can't see them. Guess I don't have visual proof, lol. Oh well, just gonna have to take my word for it.
If you refer to the thread that 9k linked to you will see the pump disassembled. It doesn't have any moving parts which are capable of displacing any oil or creating pressure of any kind. All it has the ability to do is take oil supplied by the engine oil pump and meter it through orifices in a pair of rotating cylindrical valve thingeys to a varying degree determined by the positions of the two spring loaded needle valves, whose positions are determined by the stepper motor.
EDIT*** Actually the cylindrical rotating barrel valve thingeys aren't really visible in the pictures in that thread. They are still installed in the OMP so you can't see them. Guess I don't have visual proof, lol. Oh well, just gonna have to take my word for it.
Last edited by The Underdog; 06-14-2012 at 01:48 AM.
06-14-2012, 05:04 AM
#91
Can someone provide a pic of the inlet side of the omp? Or of these "pistons" that move back and forth?
The simplest experiment could put an end to the argument of if the omp is a actual pump or a mettering device..
Fabricate a sump on the inlet side of the omp, run lines about a foot up in the air. Activate the pump, if oil makes it to the top, it's a pump, if not then it just metters oil in with the oil pump providing the pressure. Right?
Just a lot of info on here suggesting both answers.
Like why would omp adapter recommend installing the oil supply at the highest point in the engine bay, if it didn't need help from gravity to get the oil moving?
Or we could just let Team call me some more names and get nowhere...
The simplest experiment could put an end to the argument of if the omp is a actual pump or a mettering device..
Fabricate a sump on the inlet side of the omp, run lines about a foot up in the air. Activate the pump, if oil makes it to the top, it's a pump, if not then it just metters oil in with the oil pump providing the pressure. Right?
Just a lot of info on here suggesting both answers.
Like why would omp adapter recommend installing the oil supply at the highest point in the engine bay, if it didn't need help from gravity to get the oil moving?
Or we could just let Team call me some more names and get nowhere...
06-14-2012, 07:44 AM
#92
As I knew I would, I regret posting. Now it looks like I'm going to have to pull the pump back off the car and dissect it again, with pictures in order to prove my point. Not entirely sure I'm willing to do that yet.
06-14-2012, 07:48 AM
#93
06-14-2012, 08:58 AM
#94
If the pistons were in motion for the purpose of pumping oil there would have to be a check valve on the upstream side of them to prevent the oil from going back into the engine when they reversed direction.
As I knew I would, I regret posting. Now it looks like I'm going to have to pull the pump back off the car and dissect it again, with pictures in order to prove my point. Not entirely sure I'm willing to do that yet.
As I knew I would, I regret posting. Now it looks like I'm going to have to pull the pump back off the car and dissect it again, with pictures in order to prove my point. Not entirely sure I'm willing to do that yet.
Don't regret posting. I appreciate the input. If my car wasn't my dd I would have pulled the omp off by now, but I need my car everyday.
06-14-2012, 09:10 AM
#95
Registered
Here is another thread which details all this and experimenting with OMP adjustment:
https://www.rx8club.com/series-i-major-horsepower-upgrades-93/mop-adjustments-120276/
Last edited by PeteInLongBeach; 06-14-2012 at 09:18 AM.
I already linked that thread. Under dog you regret posting because someone doesn't agree with you?
06-14-2012, 10:18 AM
#97
^ I think it has more to do with how some people on here like to try to belittle others for trying or saying something different.
I lean tworads it just being a mettering device. I can't understand why it would have to "pump" the oil when there is engine oil pressure on the inlet side. It seems like it would just metter the amount of oil allowed to pass.
I lean tworads it just being a mettering device. I can't understand why it would have to "pump" the oil when there is engine oil pressure on the inlet side. It seems like it would just metter the amount of oil allowed to pass.
Team is very knowledgeable.
