SamD

Take a look at this: http://www.efunda.com/designstandard...etroleum%20Oil and note the "poor" compatibility of silicon seals with petroleum based oils. As for ATF not being a good lubricant, consider the following: it's designed to provide lubrication for gears, roller (Torrington) bearings and plain bearings (bushings). The gears themselves point to a lubricant with with good EP (extreme pressure) properties. Coupled with its ability to operate in a high heat environment, it's a good lubricant.

RVM

So are you saying ATF is good or bad for the seals in our engines?

Flyer95

My Feedback: (1)

I dont use anything since many years back and have no rust problems, but must say I use a healty amount of castor oil in my fuel.
IMO unless rusty bearings are a very known fact in your area then dont use any after run oil and dont run the engines dry. It just gives you more unwanted hassle.

anthony222

I use ******** 2- stage after run oil that I bought off ebay. It comes in a 2 pack. Blue oil to flush and red to lubricate. Interesting article about engine corrosion is listed in ******** Ad; very informative. I don't know which one is the best , but this one works well for me.

anthony222

I have been flushing and lubricating my engines with ******** after run oil, and haven't rebuilt or replaced an engine since. Great Stuff! Coudn't find at my local hobby shop, but I found it on ebay.

tonywayne

btt

tonywayne

Well I finally bought some Ultra Oil from Performance Specialties. Don’t want to take any risk with my Perry pump regulator.

N1EDM

My Feedback: (2)

Boy, this is a flashback. This was the first subject I ever posted on RCUniverse. I got a few answers, the forgot about it (I didn't know that I could have subscribed, at the time).

Anyway, I got the same diversity of answers as have been put in here. I haven't read every response, but the mixture that I use is half ATF, and half Marvel Mystery Tool Air Tool Oil... not the regular MM Oil... The Air Tool oil is supposed to get rid of moisture.

The reason that I chose that was because it was a recipe I had read in Clarence Lee's column many, many years ago. It seems to work!

Does anyone have any comments about whether this recipe is good or bad? I.e., has any new information risen about these two fluids that I should know about?

Bob

PlaneKrazee

My Feedback: (14)

One question. Should the after run oil be compatable with methanol? If it won't mix with methanol or normal glow fuel oils how will it coat anything?

Hanger 9 used to sell after run fuel. I wonder what oil it had in it. Looked like castor.

I've been using air tool oil for long term storage of my collectable engines, seems fine.

YUKONFLYR

Skypilot - I did just that back in December. Ran an engine for like 3 tanks of fuel then used afterrun oil, I like air tool oil personally and I use lots, pulled it off of the test stand and pulled the back plate off. everything was coated nicely. I did run the engine out of fuel prior....

Richard

PlaneKrazee

My Feedback: (14)

I think running the fuel out of a nice warm engine is key.

NM2K

My Feedback: (14)

---------------


Because you live in California, Dave, and you fly often. <G>

I don't normally use ARO (Marvel Air Tool Oil for non YS engines) during flying season. Most fuels, at least the fuels that I buy, have rust inhibitors in them. I do run the engines out dry at the end of each and every flying session.

Living in southwestern NJ, next to the Delaware River and Bay, rust was a problem for anything with ballbearings. Down here in northwest Georgia, the problem of rusting is nowhere near as severe as it was along the Jersey shore.

It is said that there are synthetic Air Tool Oils that are all engine safe, including YS. I'm still looking for some of that stuff. Yes, I have one YS engine left that isn't going anywhere. It is a YS .60 short stroke two-stroke. Look out BPA! <G>


Ed Cregger

Fuelman

My Feedback: (6)

Any decent air tool oil is the best bet for non pumped engines. Air tool oil has a lot of moisture scavanging properties to it and will not attack yellow metal (bushed con rods, sleeves, spray bars, etc), since it does not have sulfated chemicals in it. Think about it, air tools get full of moisture every time they're used and are full of bronze bushings, thats what this stuff is meant to protect.

For pumped engines, I like the ester based synthetic lubes like German Castrol 0W-30. Its the stuff that says made in Germany on the bottle and last I knew it was available only at Auto Zone in the US. This stuff will not soften the silicone diaphram or seals in a YS, OS pumper or perry pump.

...Or you can just add a couple percent of castor oil to the all synthetic fuels you use in your pumped engines, it will not hurt them, believe me.

Mark in Michigan

I run the engines dry after the last flight. I also use the half ATF/half air tool oil recipie and think it works good.

pete6r

Makes me laugh reading all these posts, i have never used afterun oil in my engines and have never had any problems. (i fly with saito and ys engines) some times i run my engines dry some times i dont, how your engine is set up and what fuel you use will make more differance to wear and tear than any amount of afterun oil will do.
The use of after run oil after every flying session is not nesesary like i said if your engine is set up corectly and you use a good fuel with 18-20% oils in you will be fine.
I can take my engines apart and they all have lots of oil in them already so why would i want to put more in ?
If you are that bothered about rusty bearings ie if you store your planes and engines in sheds or sellars or any other damp place then simply fit stainless steel or ceramic bearings and you will never have to worry ever again

jeffie8696

I have received engines locked up from one end to the other from dried castor. I use liquid wrench after I run an engine to protect it and keep it from gumming up.

XJet

Sorry Peter but that won't stop your crankshaft from rusting and yes they do rust.

I've seen engines with really bad rust on the crank after being run on fuel with only synthetic oil and no ARO.

And remember too that stainless steel is rust *resistant* not rust-proof.

Even the best stainless bearings will still show signs of corrosion over time.

pete6r

I too have seen rust on crankshafts and bearings but this has formed on the engine when it was brand new in the box as most makers dont oil them but certainly not from a normal running engine not in any of mine anyway, i always use fully synthetic as i think caster does more harm than good also saito dont recomend you to use it. I use 20% oil and 30 nitro and never had any probs with rusting.
If you can get a set of 440 stainless steel bearings to rust in normal running conditions then you must be doing some strange things with you engine but you could go to the extreme and fit ceramic bearings then never wory ever again although if you are like me and like using 3d props i find ceramics dont always take the load so well.
Just make sure your tank is empty after a flying session and you will be fine. i think people have problems when they store there model nose down after a weekends flying any access fuel in the tank or pipes then drains into the crankcase causing the rust.

If you are having probs with rusty cranks and bearings then you should change the fuel you are using as the lack of oil will be killing you engine anyway.

I think i am getting of topic a bit so will wind me neck in he he

Opinions are like arseholes everybody has one !

XJet

Peter, Saito actually recommend a small percentage of castor in their fuel. It's *HORIZON* in the USA who say not to use castor.

Who are you going to trust the manufacturer or their agent?

The reality is that lots of folks do have problems with rust when using fuel that has only synthetic oil, but that usually comes from using a second-tier synthetic such as Morgan's CoolPower or Klotz Techniplate.

More sophisticated hi-performance synthetics such as those commonly found in Europe offer better corrosion prevention.

All engines will benefit from just a few percent of castor in their fuel (2%-3% is all it takes).

This provides a valuable increase in film-strength at key areas such as the crankpin/conrod interface and (in the case of fourstrokes) the camshaft/lifter interface.

Lots of folks run straight synth in their engines and never have any issues.

I run a hi-tech castor/synth blend (Coopers Plus C) and have now got around 420 hours on a TT46Pro. That engine is within 200-300 RPMs of a new one. Looking inside there's no carbon build-up, no piston scuffing, no perceptible wear.

I'd like to see someone getting that sort of life out of an engine running solely a typical US-made synthetic.

I suggest you take a look at the really long Saito thread in this forum. Bill Robison has some very interesting things to say (and pictures to prove) just how much a little castor will reduce camshaft wear on a Saito.

Sport_Pilot

Actually they are rust proof, but they won't last long. Too soft. Stainless steel bearing can corrode but not with red rust, though some can rust if they are heated and cooled quickly.

Iflyglow

My Feedback: (79)

I use mobil 1 0-20 in my YS's, and Marvels in everything else.

pc55bomber

Personal choice on this sticky subject.
I run synthetic oil in everything and don't use afterun at all, I just run the fuel out of the engine, wrap a rag around it and put it away ready for the next outing. (Live on the coast so rust can be an issue).
I just replaced the bearings in my 2 enya 53 four strokers after 10 years (they weren't that bad) of the doing the above,and they are now good as new purring away in a twin.

Does not matter what you use, the internals will eventually rust up unless they are immersed in a tin of ?? oil after removing the plug for long term storage like one of our older members has done for years.
For storage I use the oil out of the oil can on my bench and a plastic bag.

Use the K.I.S.S. principal.

Cheers
Paul

Worry less.. Live more..

pete6r

Xjet all good info but i think we are getting off topic. i am sure the manufacturers spend tons of money on research for there fuels than bob in his garage does, who then changes the characteristics of the fuel by adding this or that to it.
2 or 3 % of any added oil will improve wear and tear weather caster or not.
There are better oils out there, caster is old school good for old engines to fill in the gaps of poor tolerances.
There are lots of things that goven engine life perticularly how its tuned and and warmed up before gunning it, i have seen more engines ruined by incorect tuning than i have from using caster or not or using A.R.O which is what we are meant to be arguing about he he.

Most of the people that swear by caster have grey hair He he

To tune or not to tune that is the question

Sport_Pilot

Nope, as long as it lasts past the warrenty, after that they only have a modest interest that it lasts long enough that it seems of good quality.

It is old school, but even makers of sythetic oil will tell you to use at least some castor oil on lapped engines, look at Morgans site. Check out the viscosity of synthetic oil VS castor. Castor is approximately 50 weight, synthetic oil about 20 weight. There has been little research on synthetic oils that mix's with methanol. Industry has little need for them and there isn't enough money in model aviation to pay for such research. So castor is still king.

i I can agree with that!

pete6r

sport pilot Was just wondering how stainless steel is soft ?