Slick 50 or not Slick 50?
07-08-2004, 03:45 PM
#16
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I dumped some techron in once a year or so ago. I either use Exxon/Mobil or Shell/Texaco (the Texaco station near my house switched to Shell a few months ago) 93 octane fuels in the 911 and 944 on a regular basis. Occassionally use Sunoco 94 octane.
Adrian:
Thanks for the information on U.S. vs European gas and oils. I didn't know this.
Adrian:
Thanks for the information on U.S. vs European gas and oils. I didn't know this.
07-08-2004, 05:35 PM
#17
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Thanks for the replies guys.
Seems like I'm going to have to assess the evidence presented to me.
There are a lot of for and againsts Slick 50 as referred to not only by the gurus on this and other Porsche Forums but on other web pages like the Skeptics Dictionary (see http://skepdic.com/slick50.html and http://skepdic.com/comments/slickcom.html).
I am a reliability engineer for the defense and aerospace industry, so I should trust what the what the manufacturers hand book says, but I have also learned to question "Why?" and "Is there another better method that will in the long run make the equipment work more efficiently and over a greater number of years?" - hence my question wrt Slick 50. If it can prolong the life of my beloved 964 then I want to use it.
Adrian, Why would a dry sump be any different to a wet sump wrt oil additives? It still has a reservoir to be able to store the excess oil to be able to be pumped around the system? Any Hydraulic system with a pump has to have low pressure and a high pressure sides. The reservoir need to equate the pressures, being a sealed system and all that. Surely, if you are going to have "sludge" left at the bottom of the wet sump due to the additive, you are going to have the same at the bottom of the reservoir of a dry sump? Am I being thick again?
Springer3, After working for DuPont, why do manufacturers not recommend using an additive? In you years there you must have seen the good and the "bad" lubricants to use in whatever application?
Again thanks for you help any advise.
M
964 C4 Guards Red
Seems like I'm going to have to assess the evidence presented to me.
There are a lot of for and againsts Slick 50 as referred to not only by the gurus on this and other Porsche Forums but on other web pages like the Skeptics Dictionary (see http://skepdic.com/slick50.html and http://skepdic.com/comments/slickcom.html).
I am a reliability engineer for the defense and aerospace industry, so I should trust what the what the manufacturers hand book says, but I have also learned to question "Why?" and "Is there another better method that will in the long run make the equipment work more efficiently and over a greater number of years?" - hence my question wrt Slick 50. If it can prolong the life of my beloved 964 then I want to use it.
Adrian, Why would a dry sump be any different to a wet sump wrt oil additives? It still has a reservoir to be able to store the excess oil to be able to be pumped around the system? Any Hydraulic system with a pump has to have low pressure and a high pressure sides. The reservoir need to equate the pressures, being a sealed system and all that. Surely, if you are going to have "sludge" left at the bottom of the wet sump due to the additive, you are going to have the same at the bottom of the reservoir of a dry sump? Am I being thick again?
Springer3, After working for DuPont, why do manufacturers not recommend using an additive? In you years there you must have seen the good and the "bad" lubricants to use in whatever application?
Again thanks for you help any advise.
M
964 C4 Guards Red
07-08-2004, 06:52 PM
#18
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Dear M,
Dry sump means when the engine is not running all the oil is removed from the engine and stored externally. Dry sumped engines have oil tanks not sumps to store the oil.
The oil tank has many inputs and outputs restrictor valves, check valves and over pressure valves. The inside of the tank is specially designed to remove the air from the scavenged oil before it is sent back to the engine.
If you use additives everything will be coated even the oil level float in the oil tank.
As I said you also have the other components like the thermostat valve which allows oil to flow from the engine to the oil cooler and then back to the oil tank and back to the engine.
Additives in the oil itself has an impact on all these systems hence Porsche have an approved oil table. Adding additional oil additives may cause extra problems.
Lastly but still very importantly, dry sumped, air/oil cooled engines horizontally opposed engines fitted to Porsches inherently burn oil. The lowest point of the engine is the burny bit.
The additional additives will get into the combustion side of the engine. Teflon is not known as something that burns well.
Ciao,
Adrian
964C4
Dry sump means when the engine is not running all the oil is removed from the engine and stored externally. Dry sumped engines have oil tanks not sumps to store the oil.
The oil tank has many inputs and outputs restrictor valves, check valves and over pressure valves. The inside of the tank is specially designed to remove the air from the scavenged oil before it is sent back to the engine.
If you use additives everything will be coated even the oil level float in the oil tank.
As I said you also have the other components like the thermostat valve which allows oil to flow from the engine to the oil cooler and then back to the oil tank and back to the engine.
Additives in the oil itself has an impact on all these systems hence Porsche have an approved oil table. Adding additional oil additives may cause extra problems.
Lastly but still very importantly, dry sumped, air/oil cooled engines horizontally opposed engines fitted to Porsches inherently burn oil. The lowest point of the engine is the burny bit.
The additional additives will get into the combustion side of the engine. Teflon is not known as something that burns well.
Ciao,
Adrian
964C4
07-08-2004, 09:45 PM
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Why the Shell and Mobil 1 endorsment from Porsche...anything special in the Shell gas...or is it just a paid endorsement.
I run both in my car because of the endorsement...does it matter?
I run both in my car because of the endorsement...does it matter?
07-08-2004, 11:35 PM
#20
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The melting point of Teflon PTFE is 627F/327C and the cure temperature is 805F/429C (time dependant on the material being coated). If there is PTFE in Slick50 it will stay suspended in the oil and coat absolutely nothing.
07-09-2004, 12:22 AM
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JasonAndreas is right, PTFE will not bond to metal surfaces at normal engine operating temperatures.
I've discussed these things with a friend who is both a race car driver/owner and professor of chemistry, and who has and still is performing research in this area under grants from an unnamed large company. He states that at the highest engine temperatures, the PTFE can release small amounts of fluorine that will bond to metal and provide a nearly insignificant degree of anti-wear protection, but that the PTFE itself certainly does not bond to the metals. His initial research thrust was to find a co-catalyst that would allow PTFE to bind to engine metal at lower temperatures, but he found a more promising direction that did not require the use of PTFE at all, and might eventually become commercially viable.
Even so, he did not think the new approach would provide performance superior to the zinc (ZDDP) anti-wear additives present in oil now, but it would allow zinc to be nearly eliminated from oil - a worthwhile goal since it is poison to catalytic convertors.
His position is that the PTFE anti-wear additives like Slick-50 are totally worthless.
Chip
I've discussed these things with a friend who is both a race car driver/owner and professor of chemistry, and who has and still is performing research in this area under grants from an unnamed large company. He states that at the highest engine temperatures, the PTFE can release small amounts of fluorine that will bond to metal and provide a nearly insignificant degree of anti-wear protection, but that the PTFE itself certainly does not bond to the metals. His initial research thrust was to find a co-catalyst that would allow PTFE to bind to engine metal at lower temperatures, but he found a more promising direction that did not require the use of PTFE at all, and might eventually become commercially viable.
Even so, he did not think the new approach would provide performance superior to the zinc (ZDDP) anti-wear additives present in oil now, but it would allow zinc to be nearly eliminated from oil - a worthwhile goal since it is poison to catalytic convertors.
His position is that the PTFE anti-wear additives like Slick-50 are totally worthless.
Chip
07-09-2004, 04:04 AM
#22
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Dear Targatime,
Shell and Mobil endorsements are purely commercial "Sponsorship" or as Porsche like to say "Partnerships".
They have the same with tyres and these change as well. One year it might be Conti, the next Pirelli etc etc.
Dear Chip,
Your colleague's research clearly shows a release of "Product" from the Slick 50 at high engine temperatures. The operating temperature of the 964 engine is already known to be high for its type.
I will share some additional facts with you and the forum.
A certain major oil company decided to change to additives they put in their Jet Oil to improve the its properties and commercialism of their product. The result was a whole bunch of airlines operating one specific type of turbofan engine that started to suffer a number of inflight shutdowns. The cause of these failures was traced to chemical reactions within the oil additives caused by the engine temperature which created a sludge which coated certain important parts causing compressor stalls.
Same company also recommended these oils for APUs (aux power units). The result was a whole bunch of trashed APUs. We lost 3.
Same company did a similar thing with their piston engine oils in Australia which resulted in every horizontally opposed six cylinder powered aircraft being grounded and their engines removed and overhauled due to the sludge and coating of engine components causing inflight shut downs. The white sludge found in these engines has still to this day never be properly explained.
For a practical experiment visit an engine overhaul shop. If they have an engine which has been brought in for overhaul and it has been treated with oil additives on top of the additives used in synthetic oils take a look.
You might be surprised at what you see and their comments as well along with the size of the bill.
Now this does not occur in every engine. There are so many variables it is not funny. However I have some experience in this subject because I used to do these investigations for a living. What I will say is that nothing is ever black and white.
Mixing of oil additives such as Slick 50 with modern synthetic oils which contain their own chemical cocktail of additives mixed with engine heat can cause chemical reactions and the creation of byproducts one does not want coating things in ones engine.
These are proven facts from the real world. However in the end it is always buyer beware.
There is an old Aussie oil company advert from let us say a long time ago.
"Oils ain't Oils Sol". Never more true words have been said.
Ciao,
Adrian
964C4
Shell and Mobil endorsements are purely commercial "Sponsorship" or as Porsche like to say "Partnerships".
They have the same with tyres and these change as well. One year it might be Conti, the next Pirelli etc etc.
Dear Chip,
Your colleague's research clearly shows a release of "Product" from the Slick 50 at high engine temperatures. The operating temperature of the 964 engine is already known to be high for its type.
I will share some additional facts with you and the forum.
A certain major oil company decided to change to additives they put in their Jet Oil to improve the its properties and commercialism of their product. The result was a whole bunch of airlines operating one specific type of turbofan engine that started to suffer a number of inflight shutdowns. The cause of these failures was traced to chemical reactions within the oil additives caused by the engine temperature which created a sludge which coated certain important parts causing compressor stalls.
Same company also recommended these oils for APUs (aux power units). The result was a whole bunch of trashed APUs. We lost 3.
Same company did a similar thing with their piston engine oils in Australia which resulted in every horizontally opposed six cylinder powered aircraft being grounded and their engines removed and overhauled due to the sludge and coating of engine components causing inflight shut downs. The white sludge found in these engines has still to this day never be properly explained.
For a practical experiment visit an engine overhaul shop. If they have an engine which has been brought in for overhaul and it has been treated with oil additives on top of the additives used in synthetic oils take a look.
You might be surprised at what you see and their comments as well along with the size of the bill.
Now this does not occur in every engine. There are so many variables it is not funny. However I have some experience in this subject because I used to do these investigations for a living. What I will say is that nothing is ever black and white.
Mixing of oil additives such as Slick 50 with modern synthetic oils which contain their own chemical cocktail of additives mixed with engine heat can cause chemical reactions and the creation of byproducts one does not want coating things in ones engine.
These are proven facts from the real world. However in the end it is always buyer beware.
There is an old Aussie oil company advert from let us say a long time ago.
"Oils ain't Oils Sol". Never more true words have been said.
Ciao,
Adrian
964C4
07-09-2004, 05:26 AM
#23
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Adrian,
Thank for the explanation wrt the difference between wet sump and dry sump. I should have realised that because the oil is used as an engine coolant in the boxer engine and has a lot more equipment to flow around to keep it at operating temperature than conventional wet sump, water cooled systems I have had in my previous cars.
From what I can gather, as long as I stick to the 12000 mile service and at the very least change the oil and oil filter with a good synthetic oil, my 964 should run fine for many years and mile to come.
Thanks for all of your replies.
Mark.
Thank for the explanation wrt the difference between wet sump and dry sump. I should have realised that because the oil is used as an engine coolant in the boxer engine and has a lot more equipment to flow around to keep it at operating temperature than conventional wet sump, water cooled systems I have had in my previous cars.
From what I can gather, as long as I stick to the 12000 mile service and at the very least change the oil and oil filter with a good synthetic oil, my 964 should run fine for many years and mile to come.
Thanks for all of your replies.
Mark.
07-09-2004, 11:21 AM
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Another example of additive incompatibilities: the Alaska Air flight that went down off San Diego. This was caused by a rudder worm gear failure. The worm gear was apparently serviced properly, but different (both FAA approved for the application) greases were used at two different service locations. Unfortunately, the greases (additives) were incompatible with each other and created a "concrete-like" substance after reacting together. Followed by worm gear failure. You never really know whats going to happen when you start mixing stuff *****-nilly.
Chip
Chip
