Renesis OIL PRESSURE Discussion with Dealer Tech
BS...it is not very "Common" at all, it is more common to see a Mazda Part that has had the Letter on the end changed, but when you compare Both there is no difference at all...
I can recall very few Mazda parts from the factory that have been revised without any change to the part number.
But Generally, when there is a letter change it denotes a parts change, then that can also signal a "suitability" or "supper-session" signal like AN or A, new parts can fit/replace OLD, but Old parts can Not replace/fit New, or there is NO interchangeability at all because they are totally different and this can happen from a part going from a D to an E on the end, they can be totally different.
Mazda never revises a Part that has changed and still in vehicle production without changing some part of the part number, if they did not do this they could not identify the vehicles that the revised parts were fitted to...it would be a parts and service nightmare.
I can recall very few Mazda parts from the factory that have been revised without any change to the part number.
But Generally, when there is a letter change it denotes a parts change, then that can also signal a "suitability" or "supper-session" signal like AN or A, new parts can fit/replace OLD, but Old parts can Not replace/fit New, or there is NO interchangeability at all because they are totally different and this can happen from a part going from a D to an E on the end, they can be totally different.
Mazda never revises a Part that has changed and still in vehicle production without changing some part of the part number, if they did not do this they could not identify the vehicles that the revised parts were fitted to...it would be a parts and service nightmare.
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As the guy from Pineapple Racing says, if you crush the rear valve (like putting in washers) you have to washer out the Front Oil Pump Pressure Control Valve by a similar about (in other words the washers are compressing or shortening the spring raising tension, the PSI oil Pressure)
What Mazda did in the S1 RX-8 was to use a 30 year old Rear By Pass Valve from a 13B RX-4, RX-5, FC RX-7, BUT use a different FRONT Valve spring by Part Number...So if this spring is either weaker or shorter than 73 mm from the 0839-14-273A used in the RX-4,5,7. And the Installation Hole is the same length....You Have a Winner.
Last edited by ASH8; Oct 23, 2009 at 03:39 PM.
Actually this modification shouldnt take long to do.
The pan can be dropped easily (becareful with the bolts and debri!)
out the rear bypass--do the pineapple thing and then shim the front. Thats it?
Remember to buy the 09 type filter or i do hear good things about the Fram HP-2 (bypass at 22) and its a max flow filter--big too.
Those pressures would be nice to have but for monitoring on a daily basis the oil filter plate site would be the best IMHO. That is the spot that is showing the flow to the e shaft.
OD
The pan can be dropped easily (becareful with the bolts and debri!)
out the rear bypass--do the pineapple thing and then shim the front. Thats it?
Remember to buy the 09 type filter or i do hear good things about the Fram HP-2 (bypass at 22) and its a max flow filter--big too.
Those pressures would be nice to have but for monitoring on a daily basis the oil filter plate site would be the best IMHO. That is the spot that is showing the flow to the e shaft.
OD
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Got it...
I would just like to know why or if the Front Oil Pump Valve IS the issue, because Mazda NAO re-man are not changing anything to do with the oil pressure in their rebuilds (good source) and they should be.
If it ain't the OIL it has to be pressure.
I would just like to know why or if the Front Oil Pump Valve IS the issue, because Mazda NAO re-man are not changing anything to do with the oil pressure in their rebuilds (good source) and they should be.
If it ain't the OIL it has to be pressure.
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I think changing the oil pump valve before the coolers can totally be legit, especially if the coolers acts at a sufficient restriction to the point that they cause the valve to bleed. However, it might also be somewhat difficult to make a case for this considering the people claiming that their oil pressure in front of the filter is sitting around the bleed-off pressure of the 2nd valve in the circuit. I personally think it would be more beneficial to increase the bleed-off pressure of the rear valve over the front one. But what do I know? I'm a rotarookie.
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The way I look at it is like this:
Should we be seeing this kind of bearing wear in *any* factory automoblie with low miles? No.
When we see this kind of damage, it can be only attributed to the oiling system/oil (unless there were other serious issues already).
By being able to see the comparisons between the oiling systems of various gen rotarys, it gives us a look to see where there is a possibility that in fact there is an oiling system deficiency in the Renesis S1.
The reason for the spring change is that it increases the max pressure of the oiling system. If there is too low of an oil pressure for the engine, it could be starving the bearings, which in turn would cause that sort of wear. So the thought (not currently fact) is that by raising the oil pressure (which is interrelated with flow) to the e-shafts, we could potentially eliminate bearing wear - at least much more than now.
Last edited by madcows; Oct 24, 2009 at 01:52 AM.
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I think changing the oil pump valve before the coolers can totally be legit, especially if the coolers acts at a sufficient restriction to the point that they cause the valve to bleed. However, it might also be somewhat difficult to make a case for this considering the people claiming that their oil pressure in front of the filter is sitting around the bleed-off pressure of the 2nd valve in the circuit. I personally think it would be more beneficial to increase the bleed-off pressure of the rear valve over the front one. But what do I know? I'm a rotarookie.
I think the two Oil Coolers (in the RX-8) and extra oil lines (in length) when compared to the RX-7 FC's one oil cooler which is positioned much closer to the Oil Pump would IMO have to be considered as being detrimental to the oil's pressure and flow, remember the S1 RX-8 has the exact same FC RX-7 Oil Pump, rear by pass valve and Oil Filter, etc.
The ONLY part that is different between the two models is the OIL Pumps Pressure Control Spring by Part Number. The FC's spring is said to be 73 mm long, I wish I knew the RX-8 one and it's length to compare.
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The way I look at it is like this:
Should we be seeing this kind of bearing wear in *any* factory automoblie with low miles? No.
When we see this kind of damage, it can be only attributed to the oiling system/oil (unless there were other serious issues already).
By being able to see the comparisons between the oiling systems of various gen rotarys, it gives us a look to see where there is a possibility that in fact there is an oiling system deficiency in the Renesis S1.
The reason for the spring change is that it increases the max pressure of the oiling system. If there is too low of an oil pressure for the engine, it could be starving the bearings, which in turn would cause that sort of wear. So the thought (not currently fact) is that by raising the oil pressure (which is interrelated with flow) to the e-shafts, we could potentially eliminate bearing wear - at least much more than now.
Should we be seeing this kind of bearing wear in *any* factory automoblie with low miles? No.
When we see this kind of damage, it can be only attributed to the oiling system/oil (unless there were other serious issues already).
By being able to see the comparisons between the oiling systems of various gen rotarys, it gives us a look to see where there is a possibility that in fact there is an oiling system deficiency in the Renesis S1.
The reason for the spring change is that it increases the max pressure of the oiling system. If there is too low of an oil pressure for the engine, it could be starving the bearings, which in turn would cause that sort of wear. So the thought (not currently fact) is that by raising the oil pressure (which is interrelated with flow) to the e-shafts, we could potentially eliminate bearing wear - at least much more than now.
I think you are VERY Correct..mate.
IMO Mazda made the Oil Pump spring change to boost Oil Pressure for the TWO Oil Coolers but did not raise it high enough and did not change at all the Rear By Pass Regulator controlling flows through the Eccentric Shaft, plus using Lighter weight Oils, a higher Revving Engine, Mazda Engineers Goofed on this VERY Important issue.
Even IF the S1 RX-8's OIL Pump Pressure Spring which did changed by Part Number and it has increased the pressure sufficiently, they did not change the Rear By Pass Valve Assembly or Spring which was first used in the 1976 NA 13B RX-4,5,7 (3648-14-250), so it does not matter how high the Oil Pump Pressure is, as soon as oil hits the Rear Valve on the way to the Oil filter and Eccentric Shaft it is being By Passed to PSI levels of 33 years ago...of about 60-70 PSI.
The FD RX-7's Rear Valve is 110 PSI, IMO the RX-8 should be at least 90 PSI.
Interesting stuff here.
Assuming this is correct - that the S1 RX-8 does have a lower flow to the e-shaft due to the spring in the rear relief valve, doesn't that mean (assuming a stock configuration) we should be running a thinner oil, as opposed to a thicker oil? That would ensure the maximum flow rate to the e-shaft bearing, it seems to me.
True?
Assuming this is correct - that the S1 RX-8 does have a lower flow to the e-shaft due to the spring in the rear relief valve, doesn't that mean (assuming a stock configuration) we should be running a thinner oil, as opposed to a thicker oil? That would ensure the maximum flow rate to the e-shaft bearing, it seems to me.
True?
Glad to see you are hanging around Team--whats your thoughts on this?
This may be a wack thought--but i do wonder if some of the side weal issues we see can be traced to irregular bearing wear that cause a slight off balance condition? If a "system is in tolerance" and one tolerance changes --it affects it all? I may be way out in left field on that.
Also something that hasnt been mentioned in a little while--dont forget we have 1K more rpm to deal with that the earlier models. It would stand to reason that oil flow parameters would have to be adjusted for that?
Why didnt they use the FD pump on this car? Same reason they insisted on a 5W/20 oil i guess---dumb ***? Would loose a little power and it would affect gas mileage JUST a little?
OD.
OD
This may be a wack thought--but i do wonder if some of the side weal issues we see can be traced to irregular bearing wear that cause a slight off balance condition? If a "system is in tolerance" and one tolerance changes --it affects it all? I may be way out in left field on that.
Also something that hasnt been mentioned in a little while--dont forget we have 1K more rpm to deal with that the earlier models. It would stand to reason that oil flow parameters would have to be adjusted for that?
Why didnt they use the FD pump on this car? Same reason they insisted on a 5W/20 oil i guess---dumb ***? Would loose a little power and it would affect gas mileage JUST a little?
OD.
OD
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Joined: Apr 2005
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From: Australia
Interesting stuff here.
Assuming this is correct - that the S1 RX-8 does have a lower flow to the e-shaft due to the spring in the rear relief valve, doesn't that mean (assuming a stock configuration) we should be running a thinner oil, as opposed to a thicker oil? That would ensure the maximum flow rate to the e-shaft bearing, it seems to me.
True?
Assuming this is correct - that the S1 RX-8 does have a lower flow to the e-shaft due to the spring in the rear relief valve, doesn't that mean (assuming a stock configuration) we should be running a thinner oil, as opposed to a thicker oil? That would ensure the maximum flow rate to the e-shaft bearing, it seems to me.
True?
I will just put that out there...
Thread Starter
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From: Australia
Going by what it "Thinks" it knows 'how' Mazda's Part Number System works, proves it really knows very little....close to nothing.
When it comes to Mazda Parts I can prove what I say, and I only have worked in it for almost half my life.
Talk is Cheap.
Just took my break in filter off (1K miles with 15w/40 diesel oil)--had a filter mag on it. I cut the filter apart and the magnet Works!! Collection of fine grit particles attached to the side of the can just like in their pictures they posted. No doubt-- I am sold.
Sorry for thread jack---but when i do the op mod i am also inserting a magnet in the pan.
OD
Thread Starter
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Joined: Apr 2005
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From: Australia
Just took my break in filter off (1K miles with 15w/40 diesel oil)--had a filter mag on it. I cut the filter apart and the magnet Works!! Collection of fine grit particles attached to the side of the can just like in their pictures they posted. No doubt-- I am sold.
Sorry for thread jack---but when i do the op mod i am also inserting a magnet in the pan.
OD
And the 09's (FE1032) have the internal factory Sump Pan Magnet used the first time in ANY Rotary Engines Sump (# F401-17-121).
It was used on the FC RX-7 in the Auto Transmission's Case Only, Not the FC Engine as I originally though/posted way back (sorry my bad on this one).
So, for S2 RX-8's this is the first time Mazda have installed the Auto Trans Magnet inside the Engines Revised Designed Sump Pan on Renny II.
I would recommend ALL RX-8 owners put a Filtermag or similar on their Oil Filter's case.
Lubricious
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From: SF Bay Area, California
Understood, but I was talking about the change from RX-7 to RX-8. Why change a parameter that had been used for decades? Why that one spring? It suggests that someone had a convincing reason to do so at the time.
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I believe it could have been increased as oil flows from pump through to 2 oil coolers then to Rear By Pass Valve.
It is the Rear Valve that is the issue, from there is what feeds Oil into the Oil Filter then Eccentric Shaft, you could have 200 PSI (Example) at the Oil Pump to this Rear Valve and it would make no difference as this Valve is set to By Pass at approx 60 PSI (that is the listed PSI for a 3648-14-250 Valve).
The Rear Valve Assembly 3648-14-250 in the S1 RX-8 is many decades old in design/parts, all it is is a casing with a Cylinder and a Hole in it , a spring and a piston plunger. When the Oil (Pressure) pushes the Piston Far enough past the opening or hole oil is By Passed by pressure and gravity back into the sump.
Very Simple really.
The FD RX-7 has a different Rear By Pass Valve Assembly which goes off at 110 PSI but the FD did not have the Maximum RPM that the RENESIS has.
So to increase flow to the E-shaft and Bearings you have to modify the Rear Valve otherwise just doing the front one is a waste of time.
