I own several cars, chainsaws, generators, diggers, industrial engines, lawn movers and have a collection of model steam engines. In all my years of 'playing' with engines, i've never even heard of after run oil..! Now i'm long enough in the tooth not to snub at new knowledge or education, but only a few days ago I picked up my Savage and my first ever Nitro engine. Can someone please explain to me After Run Oil, What makes a Nitro need it? Over and above any other two stroke, or any other engine. Or is it Snake oil designed only to lubricate the cash out from my wallet??
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After Run Oil
- Thread starter Neil
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fz1dave
Well-Known Member
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- 281
Nitromethane is very hydroscopic- meaning that it absorbs water easily from the atmosphere. Therefore any unburnt fuel in the engine will absorb water and cause rust. Its very important to burn all the fuel out and add oil.
Not to change the topic but some people use marvel mystery oil. Maybe someone knows if that is any better or worse?
Not to change the topic but some people use marvel mystery oil. Maybe someone knows if that is any better or worse?
griff7373
Well-Known Member
- Messages
- 334
- Location
- Windsor, VA
i used MMO for years had my picco sitting in the garage for 6 years and I treated it with MMO before I put it up, fired right up the last time I ran it.
GIRLYPANTS
Well-Known Member
- Messages
- 231
- Location
- England
Ive a brand new bottle of tornado after run oil (given to me), never used it, i will now tho, just bought a new engine and don't want it to rust up like my old 1 did, saying that tho the old f 4.6 lasted for years without ever being serviced
is this tornado brand any good ?
is this tornado brand any good ?
- Messages
- 4,790
I do not use any after run oils, when I am done for the day I spray wd40 into the carb and glow plug holes and rotate the engine a few times and put em away.....I have never had rust in any of my engines while using this.....
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- 4,790
have you ever sprayed wd40 and held a lighter up to the spraying stream, it burns off quickly and wd stands for water displacing, so in essence yes it burns off quickly and leaves virtually nothing behind....
Probably going to get burned at the stake. 
Not going to disregard the hydroscopic properties of nitromethane, but when one uses a higher quality fuel such as O'donnell's or Byron's that is available today, their oils are far superior, containing elements to combat the hydroscopicity, as-well as having better oiling properties at a lower oil content. Allowing more power at a lower temperatures.
I run O'donnel's 25%. If I'm going to be running in the next 3 days, I omit ARO. I just run the tank dry, then crank it over with an ignitor on the plug a few times to burn off any remaining nitro in the carb/cylinder. If its going to be longer, I always use ARO.
As for WD40, I will second that it works as ARO, I used it a lot when I was but a webelo. It is great at displacing water, (Water Displacement-40) spray it on a wet sheet of steel and you will see the water run in fear. However, it comes with its own issue, after some time, it becomes solidified and quite sticky. I once sprayed some on an engine that was going to be stored for unspecified amount of time, couple years later I pulled it apart. Certainly wasn't any rust to speak of, but it was quite gummed up, so much that the crank wouldn't turn freely, cleaned/reassembled and bang, fired right up.
Also WD40 has a rather high detergent content, (why it cleans so well) and spraying it on rubber seals should be avoided, just need to be sure to get the straw down into the carb past the seals, and it doesn't take much, especially coming out of an aerosol can.
So all that said, it works, but get some real ARO, its cheap.
Not going to disregard the hydroscopic properties of nitromethane, but when one uses a higher quality fuel such as O'donnell's or Byron's that is available today, their oils are far superior, containing elements to combat the hydroscopicity, as-well as having better oiling properties at a lower oil content. Allowing more power at a lower temperatures.
I run O'donnel's 25%. If I'm going to be running in the next 3 days, I omit ARO. I just run the tank dry, then crank it over with an ignitor on the plug a few times to burn off any remaining nitro in the carb/cylinder. If its going to be longer, I always use ARO.
As for WD40, I will second that it works as ARO, I used it a lot when I was but a webelo. It is great at displacing water, (Water Displacement-40) spray it on a wet sheet of steel and you will see the water run in fear. However, it comes with its own issue, after some time, it becomes solidified and quite sticky. I once sprayed some on an engine that was going to be stored for unspecified amount of time, couple years later I pulled it apart. Certainly wasn't any rust to speak of, but it was quite gummed up, so much that the crank wouldn't turn freely, cleaned/reassembled and bang, fired right up.
Also WD40 has a rather high detergent content, (why it cleans so well) and spraying it on rubber seals should be avoided, just need to be sure to get the straw down into the carb past the seals, and it doesn't take much, especially coming out of an aerosol can.
So all that said, it works, but get some real ARO, its cheap.
- Thread starter
- #10
Yes mate, to dispatch a 'Red Back Spider' when I was travelling around Australia a few years back... Lol..!
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- 4,790
http://dictionary.reference.com/browse/Hygroscopic
alcohol fuels and brake fluid are all good at taking moisture right from the atmosphere, this is why we always want to store fuel and things away from any source of moisture.....keeping the container as full as possible also helps it to remain pure and free of moisture
http://dictionary.reference.com/browse/hydroscopic
Large difference between the 2 words....
alcohol fuels and brake fluid are all good at taking moisture right from the atmosphere, this is why we always want to store fuel and things away from any source of moisture.....keeping the container as full as possible also helps it to remain pure and free of moisture
http://dictionary.reference.com/browse/hydroscopic
Large difference between the 2 words....
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- Thread starter
- #13
Yes very big difference! I just learned a new word...
Do we know how 'hygroscopic' the fuel is ?? Would a device like this detect bad fuel? Has anyone got one and tried?
http://www.amazon.co.uk/PT-Enterpri...1424654544&sr=8-1&keywords=brake+fluid+tester
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- 4,790
Seeings as there are differences in the specific gravity of the 2 fluids I doubt that device would work, although if you knew what you were looking at/for, i suppose one could make an educated estimate and go from there....
Best advice I can give is to keep your fuel storage container as full as possible and store out of sunlight and never ever store your fuels on a concrete surface. I keep mine on a shelf in the shop and never seem to have trouble with it being fresh even after storing for all winter....
Best advice I can give is to keep your fuel storage container as full as possible and store out of sunlight and never ever store your fuels on a concrete surface. I keep mine on a shelf in the shop and never seem to have trouble with it being fresh even after storing for all winter....
I may not be a chemist, but as an technician I know a couple things about tools. The tester linked above is more for quick-lube places to sell brake flushes. They measure the conductivity of the fluid, which would in theory become more conductive the higher the water content. At the dealership we use a tester that uses a small sample of the fluid and measures at what temp it boils, and how fast it does so. When compared with new sample data one can determine if the fluid is contaminated.
So, I suppose what I'm saying is, I don't see why the tester above wouldn't work on other products that are supposed to be free of water, although in my experience it won't work for what it was intended for in the first place. They will fail brand new fluid, theres too much variation brand to brand in additives, not to mention overall properties between DOT 3-5. We were advised to stay away from any tester that did not heat the fluid.
So, I suppose what I'm saying is, I don't see why the tester above wouldn't work on other products that are supposed to be free of water, although in my experience it won't work for what it was intended for in the first place. They will fail brand new fluid, theres too much variation brand to brand in additives, not to mention overall properties between DOT 3-5. We were advised to stay away from any tester that did not heat the fluid.
- Messages
- 4,790
To be honest any tool or meter to measure the SG of our fuel would probably be cost prohibitive and the best one can do is follow the steps above concerning fuel and after run oils.....
A bit of common sense is all one really needs to get the most out of our lil toy trucks and the things that go along with them.....
A bit of common sense is all one really needs to get the most out of our lil toy trucks and the things that go along with them.....
You could always use a hydrometer. Something similar to what us home brewers use to find specific gravity. I'm not sure how it would do on our fuel. But if you take a reading when you first open the jug and keep track of it you should be able to see any deviation.
BTW, hydrometers can be had for under $10 if you want something cheap to try.
BTW, hydrometers can be had for under $10 if you want something cheap to try.
RickBoblee
On a vacation
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- OK
I'm unsure of the exact count but i have over 20 engines. Coming in to the hobby I was informed how ARO is a must. So for like my first 15 engines I was a straight up phreak about. I'd use it after every run. Periodically I'd hear guys say that it was a scam, and not needed, etc,...but I still used it.
Then I got a new engine and for some reason didn't use any ARO. So in the back of my mind I thought of those guys saying it wasn't needed and decided to do a little experiment--not use it on that engine. Once the engine finally let em hang (~1.5 gallons) I thought 'hmmm.. maybe it's really not needed' as it was rolling as well as any others. I continued to use it on all my other engine though (no valid reason other than 'they are used to it'), I got two more engines during this time and also bypassed the ARO for them.
But here's what I noticed....those three engines (Werks, OS, and Nova) started on their down-slope around the 4-6 gallon mark where all my others that used ARO were still running strong after 7-10+ gallons through them.
By 'down-slope', nothing major happened with those three, but you know how an engine will at one point show decreased performance...or it might become a little more difficult to race tune, etc. Usually re-pinch, bearing replacement and/or thorough cleaning (polish sleeve and piston) gets is like new. So from then on I continued to use ARO on all new (and existing engines).
So in my opinion---and it's just based on my results not hearsay (which I don't buy in to in this hobby), I'm a believer in using it. I don't think you will incur irreversible damage not using it, but it seems to increase its performance life. Why that is the case, I cannot say I'm really not an engine guy per se. I wish I didn't have to use it but there are all sorts of theories of science that look good on paper, but no real substance to truly realize its validity. I'm unaware of any other way to judge it other than simply trying it out. I can't speak to anyone else's experiences, but that's mine (for anyone it might help).
As for break-in methods, I've tried them all. As long as you achieve the proper results (properly seat the components within a given time frame) I've seen no difference in longevity. Conceptually speaking the one thing I've seen that will hinder an engine (acutely and long term) is the type of fuel used.
Then I got a new engine and for some reason didn't use any ARO. So in the back of my mind I thought of those guys saying it wasn't needed and decided to do a little experiment--not use it on that engine. Once the engine finally let em hang (~1.5 gallons) I thought 'hmmm.. maybe it's really not needed' as it was rolling as well as any others. I continued to use it on all my other engine though (no valid reason other than 'they are used to it'), I got two more engines during this time and also bypassed the ARO for them.
But here's what I noticed....those three engines (Werks, OS, and Nova) started on their down-slope around the 4-6 gallon mark where all my others that used ARO were still running strong after 7-10+ gallons through them.
By 'down-slope', nothing major happened with those three, but you know how an engine will at one point show decreased performance...or it might become a little more difficult to race tune, etc. Usually re-pinch, bearing replacement and/or thorough cleaning (polish sleeve and piston) gets is like new. So from then on I continued to use ARO on all new (and existing engines).
So in my opinion---and it's just based on my results not hearsay (which I don't buy in to in this hobby), I'm a believer in using it. I don't think you will incur irreversible damage not using it, but it seems to increase its performance life. Why that is the case, I cannot say I'm really not an engine guy per se. I wish I didn't have to use it but there are all sorts of theories of science that look good on paper, but no real substance to truly realize its validity. I'm unaware of any other way to judge it other than simply trying it out. I can't speak to anyone else's experiences, but that's mine (for anyone it might help).
As for break-in methods, I've tried them all. As long as you achieve the proper results (properly seat the components within a given time frame) I've seen no difference in longevity. Conceptually speaking the one thing I've seen that will hinder an engine (acutely and long term) is the type of fuel used.
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- Thread starter
- #22
Very interesting... Thanks for sharing your experience.
