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Used Oil Analysis - Post Them Here

Old Dec 30, 2009 | 06:00 PM
  #76  
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Finally got my 0w-20 UOA back! I also had a TBN performed to see how long this oil could be ran. It certainly looks like a 4,000 mile oil but because my sample method was **** poor I'm questioning some of the results.

My comments for this report and all my other blogs are here.

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Old Dec 30, 2009 | 06:12 PM
  #77  
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From: macon, georgia
wow dude--maybe some thinking to do? are you running a k&n filter?
oil holding up ok but i rather have more phos and zinc in it?
OD
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Old Dec 30, 2009 | 06:22 PM
  #78  
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From: Phoenix
Originally Posted by olddragger
wow dude--maybe some thinking to do? are you running a k&n filter?
oil holding up ok but i rather have more phos and zinc in it?
OD
No I am running an AEM dryflow air filter with the sock attached to it. Although it's been some time since I checked the clamps to make sure it wasn't loose. I am willing to bet the sample picked up some particles on the oil pan itself.

I was honestly expecting this sample to be crap so it's anyone's guess. I'll check it out to be on the safe side but hopefully the next sample will show much different results.
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Old Dec 30, 2009 | 06:30 PM
  #79  
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From: macon, georgia
so your filter is outside the engine bay--right?
AEM should be ok-shouldnt it?
Hate to see that bro--those puzzles can be a real challenge.
i hear that shop vac filters wrapped around the cone filter helps-- i have one on mine!
OD
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Old Dec 30, 2009 | 06:48 PM
  #80  
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From: Phoenix
Originally Posted by olddragger
so your filter is outside the engine bay--right?
AEM should be ok-shouldnt it?
Hate to see that bro--those puzzles can be a real challenge.
i hear that shop vac filters wrapped around the cone filter helps-- i have one on mine!
OD
The filters are good for 20,000 miles but it's possible I might need to order another one. Still, a blocked filter element and one letting dirt through is totally different. It will just require me to remove the bumper and check everything out. It might give me an excuse to do some other work I need to take care of.

I'm not too concerned. This motor has about 30,000 more miles left before it gets rebuilt anyway.
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Old Dec 30, 2009 | 10:36 PM
  #81  
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What is Molybdenum? It's like 400 higher than it was in my UOA. They said my silicon was high but yours was twice as high as mine. Weird.

Also taking the sample from the oil pan as its draining is okay according to Blackstone. You said you dripped it from the pan bolt?

Also, just my thoughts but you said when you switched oils you may have left a quart or two of RP in even though you drained the coolers and I highly doubt that because when I removed my stock coolers there was only a little under a quart of oil between the two of them and all the lines. There is not as much oil still in the system as people claim there is. When I drained the oil to install the single cooler the car was on jack stands as usual. I thought there woudl be much more oil in the lines, etc. But the fact is that there just wasn't because we actually used a empty quart of Mobil1 so we would have a good measure of just how much was in the coolers and lines.

Last edited by 9krpmrx8; Dec 30, 2009 at 10:46 PM.
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Old Dec 31, 2009 | 07:25 AM
  #82  
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You normally see it as molybdenum di-sulphide in CN grease, it's a high pressure lubricant, the sulphur providing the cushioning properties as it does in titanium di-oxide, which is starting to creep in more now the price for it is getting closer to moly.
However, seeing as there's no suphur in that breakdown, it's possibly in the form of molybdenum phosphate, which helps with wear, especially at startup as it can be made to cling ionically, and provides good corrosion protection, or molybdenum-enhanced urethane, which is the more normal form, but unless I'm reading it wrong there's not enough of the rest of the required elements for it all to be contained as such.

Last edited by PhillipM; Dec 31, 2009 at 07:33 AM.
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Old Dec 31, 2009 | 09:18 AM
  #83  
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yea moly is not bad stuff--just different oils have different additive packages. Diesel oil for example has very little moly but a LOT more zinc and phos.
OD
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Old Dec 31, 2009 | 09:42 AM
  #84  
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Ah hah, good to know. Can't wait to get my UOA to see how my Mobil1 0W-40 held up.
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Old Dec 31, 2009 | 10:42 AM
  #85  
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Originally Posted by olddragger
yea moly is not bad stuff--just different oils have different additive packages. Diesel oil for example has very little moly but a LOT more zinc and phos.
OD
Zinc and phosphorous are the two that the EPA have attacked as being catalyst killers. We know that they are wear inhibitors.

Paul.
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Old Dec 31, 2009 | 11:19 AM
  #86  
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How important is zinc to the Renesis as opposed to regular engines? How important is it to regular engines? I have only heard it referenced in issues with specialized valve trains.

I noticed that in the Eneos oils that the lower weights are ILSAC GF4, but that the 0W50 is not. That is one of the reasons i had stayed with Mobil1 0W40 in my last car because they hadn't taken out the zinc.
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Old Jan 6, 2010 | 12:14 PM
  #87  
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Originally Posted by 9krpmrx8
Ah hah, good to know. Can't wait to get my UOA to see how my Mobil1 0W-40 held up.
Is it in yet? I've been running diesel, but I'm wary of it now that I know that it's high in zinc and phosphorous since I don't run a SOHN. The Euro Mobil1 would be my next choice since it covers cold starts and would hold the 40 viscosity better from shearing since it's full syn and starts with a 40 weight base. Has anyone used this oil long term on a Renesis? I remember reading in a couple of other threads that Mobil1 specifically was a syn oil that was to be avoided with rotaries, but I think that was the North American faux-syn oil.
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Old Jan 6, 2010 | 04:57 PM
  #88  
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TX Rotary Oil

As a 57 year old Exxon Oil distributor, IMO that any major Sm spec oil or any oil made since 1970 will get maximum miles outta your renesis. Yeah, I've done Blackstone lab analysis, but it's mostly to tell you if you have excess dirt, antifreeze leak, or excess fuel.
My favorite oil is Mobil 1 0w40 changed at 5,000 miles, but, diesel oil 5w40 TDT of Mobil, Shell, Chevron, or Exxon is probably good also. Flat tappet cam engines or other cams are way harder to lubricate.

I had a 1973 Rx3 that I kept ***** to the wall on 110 mph cruises with Exxon Uniflo 10w40. After a few years and 75,000 miles the water seals on the housings started seeping so I'd have to take out the plugs and heat in the oven to restart. Never was stranded. I bet it could've driven for months, all over U.S. as long as engine never cooled overnight. Imagine how you can over heat side housings without cool down stroke of 4 stroke.

The second engine went half those miles because I lowered my rear gears 10% and was driving 7000 rpm (that models redline) for 30 minutes in 100+ degree weather, and one apex seal blew with instant blub blub like hot cam. I even restarted it to drive to get used Rx4 engine. Those engines had oil flow into the carburetor with what seemed like 1,000 mile quart use for me, but in hindsight I think I would put in a few oz 2 stroke motorcycle oil in each 12 gallon fill.

Last edited by REDRX3RX8; Jan 7, 2010 at 01:17 PM. Reason: smart asses
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Old Jan 6, 2010 | 05:04 PM
  #89  
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I have not got my UOA yet but it should not be long now. Check out this spreadsheet of my MPG that I have been keeping track of since November. Notice how the MPG varies so much. There are a couple of highway road trips in there where you see the MPG bump up and teh space with no data is because i lost the damn receipt.

Last edited by 9krpmrx8; Jan 6, 2010 at 05:06 PM.
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Old Jan 6, 2010 | 07:47 PM
  #90  
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From: Australia
I pay Double that for GAS/Petrol...took $80.00 AU on Tuesday for 58 Litres...or $74.00 US Dollars!!!...

We in Australia are being RIPPED OFF by the Oil Companies...

We in Australia are being RIPPED OFF by the New Car Companies...

We in Australia we are MUGS (Fools, Dopes) for Putting up with it...
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Old Jan 6, 2010 | 08:20 PM
  #91  
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Holy crap!!! That's expensive. Keep in mind that all of these fill-ups are on Shell 93 octane, I do not fill-up with anything else.

If you notice, I actually found it for $2.53 a gallon, that was a treat.
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Old Jan 6, 2010 | 08:24 PM
  #92  
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Originally Posted by ASH8
I pay Double that for GAS/Petrol...took $80.00 AU on Tuesday for 58 Litres...or $74.00 US Dollars!!!...

We in Australia are being RIPPED OFF by the Oil Companies...

We in Australia are being RIPPED OFF by the New Car Companies...

We in Australia we are MUGS (Fools, Dopes) for Putting up with it...

Aw dear, it must be terrible, try it at $1.80 per liter...especially when it does 0.35l/km

Last edited by PhillipM; Jan 6, 2010 at 08:32 PM.
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Old Jan 6, 2010 | 08:33 PM
  #93  
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Holy *****, and I was crying a couple of summers ago when it was like $55-60 to fill-up my ride.
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Old Jan 7, 2010 | 02:48 AM
  #94  
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From: Utrecht, Netherlands
Originally Posted by 9krpmrx8
Holy *****, and I was crying a couple of summers ago when it was like $55-60 to fill-up my ride.
A 58 ltr. tankfill in the Netherlands costs USD 120,-
1 Ltr. Shell 5w30 synthetic oil costs approx USD 28,50............
At last but not at least...............latest price early 2009 of the 231hp Renesis was USD 81.500.-...........due to horrible "luxury"- and CO2 taxes...........
Only 350 RX 8's are running in the Netherlands (18.5 million inhabitants)............
Mazada-Netherlands skipped the new RX 8 in the course of 2009 from their salesprogramme since it is unaffordable with those taxes........

Best regards, Ruud

Last edited by Rudolph; Jan 7, 2010 at 03:03 AM. Reason: additional information
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Old Jan 7, 2010 | 03:12 AM
  #95  
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Originally Posted by PhillipM
Aw dear, it must be terrible, try it at $1.80 per liter...especially when it does 0.35l/km
Yes, but your distance to travel is very small compared to USA or Australia.

Isn't it funny how oil companies "scale" their Oil Prices...

Generally, small countries, higher prices, large countries (land mass) lower prices..
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Old Jan 7, 2010 | 07:20 AM
  #96  
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Isnt most of the difference usually because of taxes?
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Old Jan 7, 2010 | 08:10 AM
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Originally Posted by ASH8
Yes, but your distance to travel is very small compared to USA or Australia.
That depends how far you drive each day, I used to do 4 hours of commuting per day, 5-6 if the traffic was bad...
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Old Jan 7, 2010 | 09:30 AM
  #98  
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ever heard of technology suppression? The present day guys will maximize profit on what they have before they will allow new tecnology to be produced. We have not gotten to that point yet with oil. Probably wont in my lifetime. But my grandchildren will be driving something totally different.
OD
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Old Jan 7, 2010 | 11:24 AM
  #99  
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Originally Posted by REDRX3RX8
As a 57 year old Exxon Oil distributor, IMO that any major Sm spec oil or any oil made since 1970 will get maximum miles outta your renesis. Yeah, I've done Blackstone lab analysis, but it's mostly to tell you if you have antifreeze leak or excess fuel. My favorite oil is Mobil 1 0w40 changed at 5,000 miles, but, diesel oil 5w40 TDT of Mobil, Shell, Chevron, or Exxon is probably good also. Flat tappet cam engines or other cams are way harder to lubricate. I had a 1973 Rx3 that I kept ***** to the wall on 110 mph cruises with Exxon Uniflo 10w40. After a few years and 75,000 miles the water seals on the housings started seeping so I'd have to take out the plugs and heat in the oven to restart. Never was stranded. I bet it could've driven for months, all over U.S. as long as engine never cooled overnight. Imagine how you can over heat side housings without cool down stroke of 4 stroke. The second engine went half those miles because I lowered my rear gears 10% and was driving 7000 rpm (that models redline) for 30 minutes in 100+ degree weather, and one apex seal blew with instant blub blub like hot cam. I even restarted it to drive to get used Rx4 engine. Those engines had oil flow into the carburetor with what seemed like 1,000 mile quart use for me, but in hindsight I think I would put in a few oz 2 stroke motorcycle oil in each 12 gallon fill.
Sorry, I couldn't resist

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Old Jan 7, 2010 | 02:03 PM
  #100  
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TX synthetic motor oil

Moly additives are for extreme metal sliding and vibration that might be encountered in machinery and in car camshafts. Zinc and phosphorus react under heat as first line of anti-wear defense for sliding parts like camshafts, and moly would be second line of defense. We sold moly grease for pivot points, but if you used for bearing repack it could plate out on bearing runs like mud and run tight. Also, the sulfer in moly disulphide grease would eat rubber ball joint seals. I believe the moly compound in motor oil is different without the sulfer, so its ok if deposit control has been tested by refinery, but not necessary with RX8's nice big bearings.

Diesel engine oil has the better additives for soot control so they are usuallly best for any combustion engine.

The #1 reason for rotary failure is apex seal wear, carbon accumulation, and holding steady high rpm like 8,000 for a few minutes. My 2007 RX8 only uses 1/2 quart in 2000 miles, so I premix approx 4oz per fillup with Mobil 2t motorcycle oil which I stocked up on because they discontinued. That makes about 2/3's of seal lubricant my premix and 1/3 the Mobil 1 syn 0w40.

Two stroke motorcycles can have real bad exhaust port clogging so refiners have done lots of testing on oils that burn clean. I'm thinking thats what I want to lubricate and sweep out burned oil ash in my rotary. I think Castrol has 2t also.
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