Redline and Engine Cleanliness
- Thread starter buster
- Start date
- Status
buster,
If the statement about other synthetics producing more deposits is true,
why haven't we seen this with all of the pictures of the engines with their valve covers off?
Are there any pictures posted here on BITOG where synthetics left deposits in the 'Hot Spot' areas beneath the valve covers?
I have looked at quite a few pictures of engines with the valve covers removed, I do not remember seeing deposits in 'Hot Spot' areas...
This debate about synthetics leaving 'harder' (or worst) deposits then petroleum oil has been discussed elsewhere on BITOG, I have not seen proof of this.
Then why are there deposits in a engine run on petroleum oils?
If the statement above where true, there would be no reason to worry about deposits...
[ January 19, 2006, 01:23 PM: Message edited by: Bill ]
I agree with Bill. False marketing logic.
The thing that is missing in the argument is chemistry logic. The 4-10% (or whatever) that evaporates is NOT the stuff that leaves deposits. It's lighter volatile hydrocarbons that leave.
The thing that is missing in the argument is chemistry logic. The 4-10% (or whatever) that evaporates is NOT the stuff that leaves deposits. It's lighter volatile hydrocarbons that leave.
But consider this -- Mazda specifically warns against synthetic in their rotary RX-8's because that engine is designed to burn quite a bit of oil, and dino supposedly burns off cleaner.
Yes petroleum oil does oxidize at a lower temperature. Mixing apples and oranges.
Posted by totttalled:
How does Mazda get away with selling their Rotary engines if it pollutes the air with todays clean air laws?
and I know someone who used synthetic in their Mazda rotary with no problems...
Here is a link on BITOG about the use of synthetic in a rotary engine
Synthetic in Rotary
[ January 19, 2006, 04:24 PM: Message edited by: Bill ]
Does Mazda say not to use synthetic because of the burning off of oil or because of a seal capability issue with the synthetic?
How does Mazda get away with selling their Rotary engines if it pollutes the air with todays clean air laws?
and I know someone who used synthetic in their Mazda rotary with no problems...
Here is a link on BITOG about the use of synthetic in a rotary engine
Synthetic in Rotary
[ January 19, 2006, 04:24 PM: Message edited by: Bill ]
I'm a moderator on mazda3forums.com , and I can guarantee that the whole "no synthetic in the rotary" is a thing of the past. Plenty of RX8 owners are running synthetic in their engines without issue.
sdude, yes I know. However, the RX-8 owner's manual does advise against synthetics specifically, doesn't it? (After owning 4 Mazdas, I came about a hair's width away from buying a RX-8 a couple of months ago, deciding on a Odyssey minivan at the last second for my kids' sake.)
I offered this not to start a flame fest on whether one should or shouldn't run synthetic in the new renesis engine, but to offer anecdotal evidence in regards to buster's post concerning the Redline blurb.
I offered this not to start a flame fest on whether one should or shouldn't run synthetic in the new renesis engine, but to offer anecdotal evidence in regards to buster's post concerning the Redline blurb.
Totttalled,
I just recently purchased an RX8 myself, and there is nothing in the manual that advises against synthetics. it just says that they recommend API SL 5W-20.
as Sdude says, it's one of those nuggets that may have been half-true w/ older rotaries, but is no longer valid. I prefer to think that it comes down to 'there's not as much benefit' in dropping a synthetic into the Renesis, compared to conventional engines...as opposed to it being a bad thing altogether.
I just recently purchased an RX8 myself, and there is nothing in the manual that advises against synthetics. it just says that they recommend API SL 5W-20.
as Sdude says, it's one of those nuggets that may have been half-true w/ older rotaries, but is no longer valid. I prefer to think that it comes down to 'there's not as much benefit' in dropping a synthetic into the Renesis, compared to conventional engines...as opposed to it being a bad thing altogether.
Yes. That paragraph was from RL's old website but I took it from myoilshop.com bc they still have the old web data. They have an interesting bar graph that shows RL produces ZERO deposits. The reasoning they state is due to the polyolester basestock.
Basically the suggested that the conventional oil with it's higher evaporation rate, won't linger around as long or as much so it won't coke and form deposits. Not sure how applicable this example is to a modern engine. I guess it could be. What is interesting to note is that RL's used oil analysis could show poorly bc it will clean and keep things in suspension more so then other oils. That theory has been thrown around before, although never confirmed. Other ester based oil don't seem to show the same characteristics.
Basically the suggested that the conventional oil with it's higher evaporation rate, won't linger around as long or as much so it won't coke and form deposits. Not sure how applicable this example is to a modern engine. I guess it could be. What is interesting to note is that RL's used oil analysis could show poorly bc it will clean and keep things in suspension more so then other oils. That theory has been thrown around before, although never confirmed. Other ester based oil don't seem to show the same characteristics.
From all of the similar tests I've done with many oils including Redline, this paragraph has a mix of truth and half-truths.
"Only Red Line is capable of producing completely clean surfaces at those temperatures." Half-truth: that was in one test scenario with a few competition oils. In an engine, the oil doesn't sit and bake at 500 degrees in any location, where it can evaporate completely. It flows, so oil in one hot location is continually replaced by "fresh" oil. This test has good information about volatility and oxidative stability, but it's better to have the oils stay at 500 degrees but be in large enough quantity that they don't evaporate down to nothing since the latter scenario better represents conditions in an engine. In other words, do NOT apply this comment to what happens anywhere inside an engine: "Petroleum evaporates more readily than the synthetics, so more of the synthetic remains to thermally decompose into a hard deposit." It applies to what happened in this particular test.
I did tests where oil quantity was large enough to not boil down to nothing: Redline indeed kept metal cup very clean compared to other synthetics. I also did tests where I did boil them down to nothing and actually the Redline produced more varnish/sludge than the other synthetics. I then used scouring powder to clean all of the cups. Afterward, the Redline cup still had the most deposits. Now you can see what I mean above. How the test is run affects the outcome. And if you burn them to nothing instead of boiling you can get yet another outcome.
I also tested a straight 30 weight Pennzoil Conventional. It produced more nastiness in the cup than I've ever seen.
"Only Red Line is capable of producing completely clean surfaces at those temperatures." Half-truth: that was in one test scenario with a few competition oils. In an engine, the oil doesn't sit and bake at 500 degrees in any location, where it can evaporate completely. It flows, so oil in one hot location is continually replaced by "fresh" oil. This test has good information about volatility and oxidative stability, but it's better to have the oils stay at 500 degrees but be in large enough quantity that they don't evaporate down to nothing since the latter scenario better represents conditions in an engine. In other words, do NOT apply this comment to what happens anywhere inside an engine: "Petroleum evaporates more readily than the synthetics, so more of the synthetic remains to thermally decompose into a hard deposit." It applies to what happened in this particular test.
I did tests where oil quantity was large enough to not boil down to nothing: Redline indeed kept metal cup very clean compared to other synthetics. I also did tests where I did boil them down to nothing and actually the Redline produced more varnish/sludge than the other synthetics. I then used scouring powder to clean all of the cups. Afterward, the Redline cup still had the most deposits. Now you can see what I mean above. How the test is run affects the outcome. And if you burn them to nothing instead of boiling you can get yet another outcome.
I also tested a straight 30 weight Pennzoil Conventional. It produced more nastiness in the cup than I've ever seen.
From my reading it looks like the original quote is referring specifically to what happens in the ring and upper cylinder area. This would be an area that might be subject to near-total burn-off, wouldn't it? Especially whatever oil works its way above the oil control rings and into the recesses of the top compression ring - isn't this the particularly sensitive area that A-RX is supposed to clean most quickly, again because of the high heat?
- Glenn
- Glenn
If you go to myoilshop.com website,
there is an advertisement for Redline oil,
so, they are trying to sell Redline oil...
nothing wrong with that
except I see no proof yet that non-Ester synthetic oils (PAO) will leave more deposits then petroleum oil or Redline
there is an advertisement for Redline oil,
so, they are trying to sell Redline oil...
nothing wrong with that
except I see no proof yet that non-Ester synthetic oils (PAO) will leave more deposits then petroleum oil or Redline
For the mazda rotary - FWIW...I thought I read somewhere (it may have even been in the link provided above), that due to time constrants on engine oil compatability testing prior to it's initial market release, they were unable to complete with synthetics. Thus, I would think they didn't make any such recommendations for it's use and perhaps said not to as part of covering themselves should something have gone wrong under the warranty period. From what little I have been reading though, it seems like they've been having trouble with this engine anyway.
As JAG noted, RL left the worst and most stuborn deposits compared with other oils in his testing. With that in mind, also note that this was at temperature levels that exceed all the others, so until such temps are reached than it could indeed be the cleanest running oil in an OCI. And again as JAG noted, an engine oil is always being displaced and replenished, rather than held in a test vial over a flame, so tempuratures are not likely to remain high long enough for any one oil molecule to "cook". Of course these temperatures differ for the type of molecule.
Because of my mild driving and low yearly mileage, RL would probably work out to nothing more than excess and a drain on my resources. JMO
This is all still interesting stuff, mind you.
As JAG noted, RL left the worst and most stuborn deposits compared with other oils in his testing. With that in mind, also note that this was at temperature levels that exceed all the others, so until such temps are reached than it could indeed be the cleanest running oil in an OCI. And again as JAG noted, an engine oil is always being displaced and replenished, rather than held in a test vial over a flame, so tempuratures are not likely to remain high long enough for any one oil molecule to "cook". Of course these temperatures differ for the type of molecule.
Because of my mild driving and low yearly mileage, RL would probably work out to nothing more than excess and a drain on my resources. JMO
This is all still interesting stuff, mind you.
All this talk about oil alone, I forget to mention there's an impact on residue by the additives as well. There was mention with this concerning 2-cycle oils and ash formation. If I recall correctly, it was noted that the higher group number for the carrier oil, the less is any it contributed to ash/deposit formation. I can't recall the part about organic/inorganic, metalic or other additive composition's impact. I suppose a search in BITOG would come to the rescue!
Wish I had sustained interest in chemistry!
Wish I had sustained interest in chemistry!
Just to inform. The mazda racing team(at the same time Mazda warned about synthetic) using rotary engines, was ONLY using synthetic oil. This was in the early seventies when Mobil had some problems with their synthetic oil. It is very strange to see how long-lived these myths on synthetic oils are. Probably because someone see the value in selling you guys more oil(four times?) than you strictly need. Also when you considder the cost to produce dino versus true synthetic(not groupIII hydrocracked mineral) you will see that the oil companies want you guys to still use dino. You are being fooled all the time, but the strange thing is that you seem to like it.
Someone in our area races a rotary and uses Royal Purple. He really hammers his car and I guess it's a good thing that he does not know that synthetic oil won't work. Synthetic has been not working in his engine for five years or so and he has no major problems. He loves the stuff.
I have seen tests that shows that RP performs extremely well in rotary engines. It also keep temperature down on the engine because of reduced friction. Larry, don't tell him that he should not use synthetic. I must add that I use RP myself now, after several years testing of different oils. I have used Mobil 1 and Valvoline, plus Castrol syntec, CastrolTXT, Castrol GTX3, Castrol Magnatec, Amsoil series 3000 and some others. I ended on RP simply because it is the best choise for an engine. At least up untill now.
"Someone in our area races a rotary and uses Royal Purple. He really hammers his car and I guess it's a good thing that he does not know that synthetic oil won't work. Synthetic has been not working in his engine for five years or so and he has no major problems. He loves the stuff."
Hey, I resemble that remark! Royal Purple Racing 21 with OEM Mazda filter in a rebuilt '89 RX-7 GTUs 13B rotary. Also ran RP 15w40 in my '85 13B with 200K+ miles, never ran better and have the used oil analysis to prove it.
-JW
Hey, I resemble that remark! Royal Purple Racing 21 with OEM Mazda filter in a rebuilt '89 RX-7 GTUs 13B rotary. Also ran RP 15w40 in my '85 13B with 200K+ miles, never ran better and have the used oil analysis to prove it.
-JW
- Status
Similar threads
- Locked
- Locked
- Locked