Renesis OIL PRESSURE Discussion with Dealer Tech
12-01-2009, 09:28 PM
#751
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Well, I can certainly believe no sufficient long-term testing was done, as that would have revealed the apex seal lubrication, and side seal carbon issue, as well as cooling system issues - but those are significantly different problem than what we're talking about here. What's being suggested here is that oil flow at high RPM is not sufficient enough to lube the bearings. If that was the case, it shouldn't require much testing at all to reveal such a problem. Half hour on a bench at full throttle should reveal *something*. I would find it EXTREMELY hard to believe that mazda didn't perform the most common of engine tests.
12-01-2009, 09:52 PM
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12-02-2009, 03:28 AM
#755
Ayrton Senna Forever
.... but those are significantly different problem than what we're talking about here. What's being suggested here is that oil flow at high RPM is not sufficient enough to lube the bearings. If that was the case, it shouldn't require much testing at all to reveal such a problem. Half hour on a bench at full throttle should reveal *something*. I would find it EXTREMELY hard to believe that mazda didn't perform the most common of engine tests.
Here is an engine with higher rpm, more heat at the eccentric shaft, and with lower oil flow (pressure). How could it be possible that an enginier did not see the oppositions? Later they get it (see S2 higher flow), but what about us, with S1?
Other.. Yesterday i took out the spring of the front regulator valve, this weekend I will check its opening pressure. I hope it will be succesful and useful.
So if the 64-71 PSI is true, then a will take a shim (testing will show about the size of it) under the front valve spring as soon as possible, and later i will do the OC mod.
12-02-2009, 10:23 AM
#757
I checked with my mechanic's library that contains the maintenance specs of each car sold in italy and mazda recommends a 5w30 oil and a 10w30 as an alternative for warmer climates. In which countries mazda uses 5w20 as a factory spec other than the US?
12-02-2009, 12:29 PM
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Until we have S2 OP data, we can't say that the pressure was significantly increased at higher RPM.
I think it's important to realize that they increased pressure substantially at lower revs for a reason. Maybe it was just for the sake of the e-mop, but then again, maybe not. If it was an issue with flow at higher revs, well, the stock S1 pump still has some breath in it - it just requires that the OCVs are modified.
So that leaves the question, why did they need to increase pressure (and presumably flow) by 50% at only 3k? I'm still thinking there was a problem down low, but that's just me.
I think it's important to realize that they increased pressure substantially at lower revs for a reason. Maybe it was just for the sake of the e-mop, but then again, maybe not. If it was an issue with flow at higher revs, well, the stock S1 pump still has some breath in it - it just requires that the OCVs are modified.
So that leaves the question, why did they need to increase pressure (and presumably flow) by 50% at only 3k? I'm still thinking there was a problem down low, but that's just me.
12-02-2009, 02:28 PM
#760
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12-02-2009, 08:33 PM
#761
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Thread Starter
Not Again...
Gee, I get a little tired of repeating myself, and we are going around in circles...
AS I posted WAY back, IMO I think this 'Front' Relief Valve pressure Figures COULD be Wrong or Incorrect...why, because I will repeat this again...
The FRONT OIL PUMP Valve assembly is taken from a 1972 Mazda RX-2, and also USED in the 1985 FC RX-7, if you look up the Stats (factory) they both say the Relief Valve Pressure is 156 PSI (Like the S2 RX-8, but the S2 does not use this valve location or part numbers at all).
The Part Numbers are (0839, which is 1972 RX-2 Model Code...OK..
0839-14-115 Plunger, Control
0839-14-116 SPRING
0839-14-274 NUT or Plug (with Oil Hole in the middle)
As I have said before the S1 RX-8 has an FC OIL PUMP...OK, again they rate the relief valve pressure at 156PSI.
The Series I RX-8 has the EXACT same Parts and Part Numbers above...
The ONLY difference is the Part Number for the SPRING (which can be critical)..
That part number is S1 RX-8 SPECIFIC...(ONLY Used for the S1)
N3H1-14-237 SPRING
Same for the FD RX-7 ALL the VALVE Parts are from an RX-2 except the SPRING is
FD Specific..
N3A1-14-273A SPRING
So, One can either Buy the 3 springs to compare, or "try" an Air Test..
The S1 RX-8's SPRING would have to be either a lot weaker or shorter than the RX-2 or FC and Or FD to get such LOW Relief Valve Numbers..
If this is the case then Mazda again Boo BOOED as the front valve would By Pass Oil before the rear...which can't really be possible...could it?....the rear valve would never or hardly work?..
So are these "Factory" numbers correct???, if they are WHY are Mazda Not rectifying this error when they do the RE-Mans in the USA??
Again...I will repeat...the REAR BY PASS VALVE is Mazda Part #
3648-14-250 (From the RX-4 and RX-5), and is used on all FC-RX-7's and ALL Series 1 RX-8's..
So, the ONLY Difference in the OILING SYSTEM between the FC RX-7 and S1 RX-8 by FACTORY PART NUMBERS are the Front Valve Spring, and the use of TWIN Oil Coolers (except Australia and Japan)..
AGAIN IMO the reason we are seeing Poor PSI numbers in the USA ( particularly in the lower Rev range) is because of Oil Viscosity and the FACT that TWIN Oil Coolers "lower" the Engines OIL Pressure, that is the OIL Pressure at the OIL Filter Pick Up Area, BEFORE it goes into the e-shaft.
AS I posted WAY back, IMO I think this 'Front' Relief Valve pressure Figures COULD be Wrong or Incorrect...why, because I will repeat this again...
The FRONT OIL PUMP Valve assembly is taken from a 1972 Mazda RX-2, and also USED in the 1985 FC RX-7, if you look up the Stats (factory) they both say the Relief Valve Pressure is 156 PSI (Like the S2 RX-8, but the S2 does not use this valve location or part numbers at all).
The Part Numbers are (0839, which is 1972 RX-2 Model Code...OK..
0839-14-115 Plunger, Control
0839-14-116 SPRING
0839-14-274 NUT or Plug (with Oil Hole in the middle)
As I have said before the S1 RX-8 has an FC OIL PUMP...OK, again they rate the relief valve pressure at 156PSI.
The Series I RX-8 has the EXACT same Parts and Part Numbers above...
The ONLY difference is the Part Number for the SPRING (which can be critical)..
That part number is S1 RX-8 SPECIFIC...(ONLY Used for the S1)
N3H1-14-237 SPRING
Same for the FD RX-7 ALL the VALVE Parts are from an RX-2 except the SPRING is
FD Specific..
N3A1-14-273A SPRING
So, One can either Buy the 3 springs to compare, or "try" an Air Test..
The S1 RX-8's SPRING would have to be either a lot weaker or shorter than the RX-2 or FC and Or FD to get such LOW Relief Valve Numbers..
If this is the case then Mazda again Boo BOOED as the front valve would By Pass Oil before the rear...which can't really be possible...could it?....the rear valve would never or hardly work?..
So are these "Factory" numbers correct???, if they are WHY are Mazda Not rectifying this error when they do the RE-Mans in the USA??
Again...I will repeat...the REAR BY PASS VALVE is Mazda Part #
3648-14-250 (From the RX-4 and RX-5), and is used on all FC-RX-7's and ALL Series 1 RX-8's..
So, the ONLY Difference in the OILING SYSTEM between the FC RX-7 and S1 RX-8 by FACTORY PART NUMBERS are the Front Valve Spring, and the use of TWIN Oil Coolers (except Australia and Japan)..
AGAIN IMO the reason we are seeing Poor PSI numbers in the USA ( particularly in the lower Rev range) is because of Oil Viscosity and the FACT that TWIN Oil Coolers "lower" the Engines OIL Pressure, that is the OIL Pressure at the OIL Filter Pick Up Area, BEFORE it goes into the e-shaft.
12-02-2009, 08:38 PM
#762
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Thread Starter
PAUL...surely you and or Mr. E could compare these front Relief Valve Springs???..
To put us out of our misery...
The Only difference 'could' be that the S1 RX-8 spring has a "special" coating on it when compared to the FC (RX-2) one, but are identical in size and spring load.
If the Front valve does little work then why has the FD got a specific one, as far as I am aware the FD's Relief valve pressure is also 156 PSI?
Edit...But the FD, like the FC Turbo (both have the same Oil Pumps) have larger displacement Oil Pumps (Rotors are 5 MM wider..each).
To put us out of our misery...
The Only difference 'could' be that the S1 RX-8 spring has a "special" coating on it when compared to the FC (RX-2) one, but are identical in size and spring load.
If the Front valve does little work then why has the FD got a specific one, as far as I am aware the FD's Relief valve pressure is also 156 PSI?
Edit...But the FD, like the FC Turbo (both have the same Oil Pumps) have larger displacement Oil Pumps (Rotors are 5 MM wider..each).
Last edited by ASH8; 12-02-2009 at 08:44 PM.
12-02-2009, 10:40 PM
#763
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Indeed! Someone test these springs, PLEASE!
Ash, as I've been saying quite a bit lately, I really don't think it's the pressure in the upper rev band that's the problem. If this is indeed true, then simply changing the regulator springs (front and rear) will do nothing, unless perhaps you're trying to run higher visc oil. A higher capacity pump (like the FD's, or S2's) is an absolute necessity.
Mazda most certainly had done plenty of high speed testing on the S1 renesis, but wouldn't be surprised if they almost completely neglected proper low speed - high load testing.
We do know the stock cooling system on the S1 is restrictive - but I think they're indirectly affecting OP. Here's why:
If you supply a fixed volume of a fluid over a given time through a circuit (like that coming from the positive displacement oil pump), the more restrictive a particular path may be (like an oil cooler), the higher the pressure will be in front of that path. However, the flow rate would ideally always be the same (unless cavitation is occuring) in the end. With that said, the oil pressure being measured at the next point of restricting (in our case, in front of the rear bypass & filter) should be the same regardless of the prior restriction, as long as fluid volume had not been altered. Since people have been seeing an increase in pressure at this location, it leaves me to believe the the volume IS being affected - and the only place it could be affected at is in front of the first point of restriction - the oil coolers. The pressure in front of the stock coolers is certainly higher than what would be created by a higher efficiency cooler. If the specs that you have posted are indeed correct (and it sounds like they are), then the restriction caused by the stock coolers are causing the front bypass to open - a condition that is not happening (at least to the same extent) when a lower restriction cooler is used.
I'm willing to bet that by simply shimming the front bypass, OP measured at the oil filter will be increased - a scenario that would not happen if the front bypass was actually rated for ~150psi. However, it should be noted that it is possible that the stock coolers are not designed to properly handle the increase in pressure, so it might be a bit risky.
Ash, as I've been saying quite a bit lately, I really don't think it's the pressure in the upper rev band that's the problem. If this is indeed true, then simply changing the regulator springs (front and rear) will do nothing, unless perhaps you're trying to run higher visc oil. A higher capacity pump (like the FD's, or S2's) is an absolute necessity.
Mazda most certainly had done plenty of high speed testing on the S1 renesis, but wouldn't be surprised if they almost completely neglected proper low speed - high load testing.
We do know the stock cooling system on the S1 is restrictive - but I think they're indirectly affecting OP. Here's why:
If you supply a fixed volume of a fluid over a given time through a circuit (like that coming from the positive displacement oil pump), the more restrictive a particular path may be (like an oil cooler), the higher the pressure will be in front of that path. However, the flow rate would ideally always be the same (unless cavitation is occuring) in the end. With that said, the oil pressure being measured at the next point of restricting (in our case, in front of the rear bypass & filter) should be the same regardless of the prior restriction, as long as fluid volume had not been altered. Since people have been seeing an increase in pressure at this location, it leaves me to believe the the volume IS being affected - and the only place it could be affected at is in front of the first point of restriction - the oil coolers. The pressure in front of the stock coolers is certainly higher than what would be created by a higher efficiency cooler. If the specs that you have posted are indeed correct (and it sounds like they are), then the restriction caused by the stock coolers are causing the front bypass to open - a condition that is not happening (at least to the same extent) when a lower restriction cooler is used.
I'm willing to bet that by simply shimming the front bypass, OP measured at the oil filter will be increased - a scenario that would not happen if the front bypass was actually rated for ~150psi. However, it should be noted that it is possible that the stock coolers are not designed to properly handle the increase in pressure, so it might be a bit risky.
12-03-2009, 03:02 AM
#766
Super Moderator
Thread Starter
Sorry only 1989 FC...RX-7..
Many things are similar or same for S1 RX-8, except Middle Oil Cooler, MOP Nozzles and Turbo Line (if fitted).
Many things are similar or same for S1 RX-8, except Middle Oil Cooler, MOP Nozzles and Turbo Line (if fitted).
12-03-2009, 07:33 AM
#767
Ayrton Senna Forever
Gee, I get a little tired of repeating myself, and we are going around in circles...
AS I posted WAY back, IMO I think this 'Front' Relief Valve pressure Figures COULD be Wrong or Incorrect...why, because I will repeat this again...
The ONLY difference is the Part Number for the SPRING (which can be critical)..
AS I posted WAY back, IMO I think this 'Front' Relief Valve pressure Figures COULD be Wrong or Incorrect...why, because I will repeat this again...
The ONLY difference is the Part Number for the SPRING (which can be critical)..
So, One can either Buy the 3 springs to compare, or "try" an Air Test..
If this is the case then Mazda again Boo BOOED as the front valve would By Pass Oil before the rear...which can't really be possible...could it?....the rear valve would never or hardly work?..
So are these "Factory" numbers correct???, if they are WHY are Mazda Not rectifying this error when they do the RE-Mans in the USA??
This made the Mazdas so reliable in the past, but it's not true in the case of the Renesis. They had the Renesis S1 for about a decade before the S2 came out.
Again...I will repeat...the REAR BY PASS VALVE is Mazda Part #
3648-14-250 (From the RX-4 and RX-5), and is used on all FC-RX-7's and ALL Series 1 RX-8's..
3648-14-250 (From the RX-4 and RX-5), and is used on all FC-RX-7's and ALL Series 1 RX-8's..
12-03-2009, 07:49 AM
#768
Ayrton Senna Forever
Indeed! Someone test these springs, PLEASE!
We do know the stock cooling system on the S1 is restrictive - but I think they're indirectly affecting OP. Here's why:
If you supply a fixed volume of a fluid over a given time through a circuit (like that coming from the positive displacement oil pump), the more restrictive a particular path may be (like an oil cooler), the higher the pressure will be in front of that path. However, the flow rate would ideally always be the same (unless cavitation is occuring) in the end. With that said, the oil pressure being measured at the next point of restricting (in our case, in front of the rear bypass & filter) should be the same regardless of the prior restriction, as long as fluid volume had not been altered. Since people have been seeing an increase in pressure at this location, it leaves me to believe the the volume IS being affected - and the only place it could be affected at is in front of the first point of restriction - the oil coolers. The pressure in front of the stock coolers is certainly higher than what would be created by a higher efficiency cooler. If the specs that you have posted are indeed correct (and it sounds like they are), then the restriction caused by the stock coolers are causing the front bypass to open - a condition that is not happening (at least to the same extent) when a lower restriction cooler is used.
I'm willing to bet that by simply shimming the front bypass, OP measured at the oil filter will be increased - a scenario that would not happen if the front bypass was actually rated for ~150psi. However, it should be noted that it is possible that the stock coolers are not designed to properly handle the increase in pressure, so it might be a bit risky.
We do know the stock cooling system on the S1 is restrictive - but I think they're indirectly affecting OP. Here's why:
If you supply a fixed volume of a fluid over a given time through a circuit (like that coming from the positive displacement oil pump), the more restrictive a particular path may be (like an oil cooler), the higher the pressure will be in front of that path. However, the flow rate would ideally always be the same (unless cavitation is occuring) in the end. With that said, the oil pressure being measured at the next point of restricting (in our case, in front of the rear bypass & filter) should be the same regardless of the prior restriction, as long as fluid volume had not been altered. Since people have been seeing an increase in pressure at this location, it leaves me to believe the the volume IS being affected - and the only place it could be affected at is in front of the first point of restriction - the oil coolers. The pressure in front of the stock coolers is certainly higher than what would be created by a higher efficiency cooler. If the specs that you have posted are indeed correct (and it sounds like they are), then the restriction caused by the stock coolers are causing the front bypass to open - a condition that is not happening (at least to the same extent) when a lower restriction cooler is used.
I'm willing to bet that by simply shimming the front bypass, OP measured at the oil filter will be increased - a scenario that would not happen if the front bypass was actually rated for ~150psi. However, it should be noted that it is possible that the stock coolers are not designed to properly handle the increase in pressure, so it might be a bit risky.
If a day would be 36 hours....
12-03-2009, 08:22 AM
#770
PAUL...surely you and or Mr. E could compare these front Relief Valve Springs???..
To put us out of our misery...
The Only difference 'could' be that the S1 RX-8 spring has a "special" coating on it when compared to the FC (RX-2) one, but are identical in size and spring load.
If the Front valve does little work then why has the FD got a specific one, as far as I am aware the FD's Relief valve pressure is also 156 PSI?
Edit...But the FD, like the FC Turbo (both have the same Oil Pumps) have larger displacement Oil Pumps (Rotors are 5 MM wider..each).
To put us out of our misery...
The Only difference 'could' be that the S1 RX-8 spring has a "special" coating on it when compared to the FC (RX-2) one, but are identical in size and spring load.
If the Front valve does little work then why has the FD got a specific one, as far as I am aware the FD's Relief valve pressure is also 156 PSI?
Edit...But the FD, like the FC Turbo (both have the same Oil Pumps) have larger displacement Oil Pumps (Rotors are 5 MM wider..each).
No misery is necessary. We always measure all of these and make comparisons. Rick did it years ago. I'll ask him shortly for the info.
I'll have another thread within days to cover 09 observations since we have some stuff to share.
Paul.
12-03-2009, 10:02 AM
#772
SARX Legend
iTrader: (46)
Great!!! Thanks. So having the oil temperature gauge at the filter location is a good spot to measure after the cooler. So when I'm seeing 200F the oil is probably like 220F going in to the cooler and even hotter in the engine.
Last edited by 9krpmrx8; 12-03-2009 at 10:08 AM.
12-03-2009, 12:02 PM
#775
