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Winter Oil, Aviation oil/auto oil

Put a quart of each in your freezer for a week. then take them out and pour them out. you'll probably see the difference. (altho Ive never tried this). the Aeroshell always had instant pressure. cant say the same for Phillips
Well ya that's the difference between 20 and 15 weight, even a Texan won't take that bet...
 
I was trying to be serious.
After this Poke.
I decided not to post anymore.
This is a forum, you have to take the serious with the not so serious and the good advice from the poor advice.
I will say that video of the shell game guy is amazing. You could lose your weeks paycheck to him.
 
as for oil dilution.... its old as the hills, 1930's at least. the old timers used it, the military too back when they still had piston engines. the oil sumps on radials have a hopper inside to allow fuel to circulate with a limited quantity of oil at shut down. that gives "loose" oil for the next start. then as the engine ran, the fuel would evaporate off, the warm oil thawing the cold oil. it was common on Beavers & Otters for sure. I know Continental made an oil dilution system for the big 6 cylinder engines, but I never worked on one. no reason it wouldn't work but finding the parts would be tough & I don't remember seeing anything for four cylinder engines ever.
 
I seem to remember that one of the options which Cessna offered for the 1970s 180/185 was an oil dilution system.
 
There is a solenoid valve which feeds fuel from the gascolator into a fitting on the engine. You turn it on for a prescribed number of seconds, depending on the expected temperatures, just before shutting down the engine. The gas thins the oil and burns off after starting.
 
My '75 180J had a factory oil dilution system installed when new. Frequent oil changes must have been more important.
 
as for oil dilution.... its old as the hills, 1930's at least. the old timers used it, the military too back when they still had piston engines. the oil sumps on radials have a hopper inside to allow fuel to circulate with a limited quantity of oil at shut down. that gives "loose" oil for the next start. then as the engine ran, the fuel would evaporate off, the warm oil thawing the cold oil. it was common on Beavers & Otters for sure. I know Continental made an oil dilution system for the big 6 cylinder engines, but I never worked on one. no reason it wouldn't work but finding the parts would be tough & I don't remember seeing anything for four cylinder engines ever.
International Harvestor used to make Diesel tractors that had spark plugs and a separate gas and diesel tank. They started on gas and then the operator switched them over to diesel once running. There are many ways to skin a cat.
Having said that , just because it used to be done, does not mean it is the best method. I am not so young to remember that it was thought that smoking was good for your health. It was also believed that one should not sail too far into the horizon or you would fall off the edge of the earth. It is possible that occasionally the old timers got it wrong.
Just Sayin' :pop:
 
So far the 5W30 test is going well. Cold pressures are 45 psi from start up which is better than the 80 or more that I was getting with a cold(ish) engine. As hot as I can get the engine, (oil still under 140F, ) the pressure holds at 45 which is what W80 was holding at in the summer. Idle, warm, it holds at 30psi which is higher than the W80 held at idle in the summer when hot.
My conclusion is aviation oil should be available in thinner viscosity than 15W50.
 
Use the aviation Multi-grade oil. An example would be Aeroshell 15W50 flows like a 15w oil when the engine is cold and protects like a 50w when the engine is up to operating temp. The Automotive oils do not handle the lead scavenging that the aircraft oils are designed to do.


Since I run strictly 91 auto fuel in my 85hp, I should not have to worry about lead.

Zenairdave: what oil specifically are you running? I really find it hard to justify $120+ for 12 pk av oil up here. I'm real tempted to try diesel oil like Rotela thinking it may lend itself better to flat tappet type engines as opposed to roller rockers & modern auto oil.
Thought?
 
My thought is if you do it don't carry anyone else in your plane as they look to the pilot to keep them safe. Don't fly over any property you don't own. Don't fly over any people. Have fun.
 
Since I run strictly 91 auto fuel in my 85hp, I should not have to worry about lead.

Zenairdave: what oil specifically are you running? I really find it hard to justify $120+ for 12 pk av oil up here. I'm real tempted to try diesel oil like Rotela thinking it may lend itself better to flat tappet type engines as opposed to roller rockers & modern auto oil.
Thought?

As a precursor, Remember----your results may vary.

The purpose of my experiment was not about saving money over the price of oil, it was about causing less harm to a cold engine with thick oil that will not circulate at cold temperatures. When it does start to circulate, it is likely bypassing the screen/oil filter until warmed up significantly. These are not desirable issues.
Other things I considered that were likely happening with cold thick oil.
Hyd. lifters not able to fill/adjust, oil not able to pass bearings making hot spots, oil not returning to pan, rings unable to scrap the cylinder properly nor get the gel out of the rings.
Potential risks with car oil include, not being able to handle lead, detergents that clean 50 years of sludge from internals and plug the screen, some secret ingredient that eats 75 yr old metal or seals. Maybe its not as slippery as Aviation oils??
When aero shell comes out with 5W30, I will gladly buy it at whatever price. Until then, the Castrol GTX synthetic blend for high mileage engines is what seems to be working. I was warned by someone to make sure it is rated with SL from API.
I never checked what that was because on the back it has stamped, meets SN,SM,SL,SJ. Whatever that rating is, it has it.
In the end, it's your engine, your money, your choice. Do what you want at your own risk.
 
My thought is if you do it don't carry anyone else in your plane as they look to the pilot to keep them safe. Don't fly over any property you don't own. Don't fly over any people. Have fun.

Clearly you would never fly an experimental aircraft anywhere, auto conversions would be out of the question. You must put new tires on your vehicles every year because rubber deteriorates and could cause a blow out. Do you have assistance when you climb a set of stairs or get in the bath tub? :cheers
 
I did say have fun! I've done enough test flying and stated my basic rules when doing it. Been flying since 66' and good lord willing I'll be around a bit longer, sorry to offend you.
 
I did say have fun! I've done enough test flying and stated my basic rules when doing it. Been flying since 66' and good lord willing I'll be around a bit longer, sorry to offend you.
Not so much offended as frusturated. The certified aviation world is stuck in 1960 because the authorities are convinced that if you do something that was not tested 50 years ago, the plane is going to crash and kill everyone nearby.
While that might happen, with a bit of caution, it likely won't.
Also I have been around long enough to know if someone wants to sue you, there is a lawyer somewhere that can find something you did which caused his clients grief. That is a fact but I prefer not to live my life being scared of that lawyer hiding in the bushes.
 
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I think you would find most of us old guys agree with you on everything you said, but have lost lots for friends over the years. That said how about making a test stand and mic everything and take pic's to compare and run the engine several hours and really see what happens to all the components, both in size and color changes ( heat problems ). It would be hard to tell if it were flown, too many variables.
A side note on cert. Parts- Cessna door handle 275.00 1963 ford falcon 21.00. The diference is the Cessna part # ends with a -C. They didn't even go to the trouble to change the #.
 
Not so much offended as frusturated. The certified aviation world is stuck in 1960 because the authorities are convinced that if you do something that was not tested 50 years ago, the plane is going to crash and kill everyone nearby.
While that might happen, with a bit of caution, it likely won't.
Also I have been around long enough to know if someone wants to sue you, there is a lawyer somewhere that can find something you did which caused his clients grief. That is a fact but I prefer not to live my life being scared of that lawyer hiding in the bushes.

What he's getting at is; experiment away. More power to you and, as a matter of fact, most of us ARE interested in any results you may come up with. But, in the process of experimenting, make sure not to hurt anyone. You may think something is perfectly safe, but until you put flight time and measurements to it, you'll never know for sure. We don't need to lose family or friends (or even enemies) and when someone crashes while doing something 'unusual', it makes all of us look bad to the non flying public.

Web
 
I have a couple of questions for someone who knows the science. Most of us are familiar with ashless dispersent oil. As I understand it that's the aviation alternative to detergent oil, the difference being that technically speaking detergents are metallic compounds and they leave ash residue. Is that residue because of our use of leaded fuel or is it that our airplane engines being 4-cycle air cooled are unusual in that we routinely operate in the 400* CHT range (well above what our liquid cooled engines run)? I recall stories about detergent oils causing valve problems but never understood the science of why. I have talked to a couple of famous aviation oil guys about things like STP and they still reject additives that use metallic components. Does anyone here know the real answer?
 
I was racing cars in the 60' and 70's and the factory guys told me if they found traces of STP on the parts they were dropped from the factory program. It was explained to me that the molecules were long and thin and would brake down and not lub under high presure and heat.
 
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