Model Aircraft Engine Refurb

[Chris Murphy]

Same here in Aus...... local Shell service station ....purple fuel.....bloke there had a 44 gallon drum and we could get any volume at a time, only 12 years old so usually 1 pint was all I could afford.(before metric here then)

Actually still have a 500ml bottle of diesel fuel in the workshop cupboard that has been there since 1990.
I was surprised that it was still good after all that time.
Had a flood here in 2013 that took nearly all my gear but the old Victa mower survived.
After a month of being full of crap water, pulled the plug and washed out with everything known but it wouldn't go.
Gave it a drink of that diesel fuel and I had to chase it around the block to catch it.
Still going today.

Trouble finding diesel fuel these days......PAW engine has been sitting for a while now waiting.

Talk to your local C/L club-they're normally still big users of diesel-and usually have some arrangements for either selling fuel in quantity or have legitimate access to the ingredients and will generally sell to bona fide modellers.

 

[josodl1953]

As far as I know diesels will take any kind of combustible hydrocarbons as long as you add sufficient ether to the mix.
I've run diesels on 25% castor, 25% ether and 50% turpentine (paint thinner, white spirit or whatever it is called)

Jos

 

[bluejets]

Talk to your local C/L club-they're normally still big users of diesel-and usually have some arrangements for either selling fuel in quantity or have legitimate access to the ingredients and will generally sell to bona fide modellers.

That would be my first approach but the local club here have no facility for control line and it is essentially banned given there is no flying area set aside.

I did find some detail from an old Aussie/NZ mag on alternatives...

 

[Steamchick]

On ultrasonic cleaner. Almost all domestic " kitchen and worksurface cleaners" are caustic, so good for degeasing. - just 1 or 2 squirter hi to warm water in the ultrasonic bath. If not greasy, a pinch of salt is good enough. But NOT for aluminium and aircraft alloys! Use the bottle of " window cleaner" instead. This must be acidic, to avoid chemically etching the glass, so is a good cleaner in the ultrasonic water bath. - or vinegar, or sour wine, (the dregs left in a bottle from a month ago...), or lemon juice, if you have a tree and they are free...
All you want is to create some free ions to pick up the muck into suspension after the ultrasonic energy has blasted it off the surface.
But don't drink the dirty ultrasonic waste water! - toxic!

 

[Steamchick]

On diesel fuels... most organic and inorganic oils will burn in diesels. Just need enough ether and compression to ignite the fuel. But don't fogey the lube oil. Many fuels - eg paraffin based, turps substitute, etc. - have no lubricity. So that's why you stuff in up to 25% lube oil. Thin stuff on the models. Otherwise you'll get lots of rapid wear or siezures.
Enjoy

 

[Chris Murphy]

That would be my first approach but the local club here have no facility for control line and it is essentially banned given there is no flying area set aside.

I did find some detail from an old Aussie/NZ mag on alternatives...

I would take some of those alternatives-with a large tablespoon of salt.....remember model 'diesels' have been around since 1930-90 years-and in all that time no better substitute has been found for diethyl ether-simply (and now wearing my chemistry PhD hat) because there is no other organic compound in existence with the same combination of flammability, self ignition temperature, miscibility and explosive limits. ....what all these 'alternative non ether ' fuels conveniently forget to mention is that whilst the engine may run on them (and they do) they won't START on them from cold-and either require you to preheat the engine to operating temperature, or to use a normal ether based fuel for the initial startup. Secondly-if they do run adequately-they require a much higher compression setting to sustain running-which puts a lot more stress on the engine and can result in rod and/or crankpin failure. Historically, the fixed head compression diesels of the late 40s-Micron in France, Owat in the UK and Drone in the US ran on a simple ether-oil mixture-no kerosene was used-and the fuel was tailored to suit the propeller load-more ether-less oil and vice versa-to achieve smooth running

 

[awake]

Historically, the fixed head compression diesels of the late 40s-Micron in France, Owat in the UK and Drone in the US ran on a simple ether-oil mixture-no kerosene was used-and the fuel was tailored to suit the propeller load-more ether-less oil and vice versa-to achieve smooth running

So, you're saying it is an ether-or situation?

 

[Chris Murphy]

So, you're saying it is an ether-or situation?

Only if your head is fixed....;-(

 

[awake]

My wife tells my my head NEEDS to be fixed ... or was that examined? Something like that.

 

[josodl1953]

Yeah, right...

The basic idea to use another combustible in additon to the dimethylether is that the the caloric value of ether is rather low. So basically is is possible to run a model diesel on ether and castor oil only but if you want to improve performance it is mecessary to add something more powerful like white spirit or kerosene. Diesels have a lower specific power compared to glow engines so if you want the engine to propel somthing is is better to keep the ether percentage as low as possible.

As far as cleaning is concerned: I have a vast collection of old engines ,most of them stored without proper cleaning after the last run ( yes, shame on me..) and every now and then I pick one and put it in a jar filled with thinner.
This is a powerful solvent and it dissolves all gummed up castor oil without corroding the metal.

Chemical products break up the oil molecules but sometimes also the metal the engine is made of....
50 years of collecting model engines ( not to mention the loose parts..)

Jos

 

[Rocketrob]

Jos,
You have some real Whatzits in that case! Very nice.

 

[Rocketrob]

Chris,
Is it true you pursued your Chemistry PHD as a result of your quest for an etherless model diesel fuel?

 

[awake]

Chris,
Is it true you pursued your Chemistry PHD as a result of your quest for an etherless model diesel fuel?

No, I believe he was trying to come up with a diesel fuel that used salt:

I would take some of those alternatives-with a large tablespoon of salt.....

 

[bluejets]

I would take some of those alternatives-with a large tablespoon of salt.....remember model 'diesels' have been around since 1930-90 years-and in all that time no better substitute has been found for diethyl ether

That's all well and good but the fact is that the ether is impossible to find these days except if one happens to belong to a club which promotes control line flying, so it really is not an alternative. Starting would be no problem as there is always a can of "start ya barstard" ...

 

[Mikefrear]

Yeah, right...

The basic idea to use another combustible in additon to the dimethylether is that the the caloric value of ether is rather low. So basically is is possible to run a model diesel on ether and castor oil only but if you want to improve performance it is mecessary to add something more powerful like white spirit or kerosene. Diesels have a lower specific power compared to glow engines so if you want the engine to propel somthing is is better to keep the ether percentage as low as possible.

As far as cleaning is concerned: I have a vast collection of old engines ,most of them stored without proper cleaning after the last run ( yes, shame on me..) and every now and then I pick one and put it in a jar filled with thinner.
This is a powerful solvent and it dissolves all gummed up castor oil without corroding the metal.

Chemical products break up the oil molecules but sometimes also the metal the engine is made of....View attachment 116328
50 years of collecting model engines ( not to mention the loose parts..)

Jos

Hi Jos, have you any Taplins you would sell? Regards Mike

 

[josodl1953]

No, I don't have Taplins. The twin belongs to the most desirable classic diesels and if I had one, I probably would not sell it. Most of my engines are more or less run-down middle of the road engines used for boat racing and C/L flying.

Jos

 

[Chris Murphy]

Gents-the compound in question is di-ETHYL ether, not di-methyl ether or ethe- methyl ether or any other ether you stumble across, nor 'petroleum ether' nor 'crown ether' either......if our Dutch resident friend above was trying to use dimethyl ether he would have been in for some technical difficulties-it being a gas for a start not a liquid [in fact it is the simplest of the ethers-and boils at -24C.....even in the Netherlands...I doubt it gets that cold even in winter!] When talking chemistry-as it applies to model engine fuels-you need to know what you're talking about-and be accurate. (some of us do-and are...!)

 

[josodl1953]

Well,if you say so Chris, I'll take your word for it, it 's been a long time since I had chemistry lessons at school. The only thing I seem to remember is that di- methyl ether is CH3 - O - CH3 and di-ethyl ether is
CH3 - CH2- O- CH2 - CH3 . Bottomline is that the product we all are referring to is the stuff used as an anaesthetic in the old days but then again , if you say it is di-ethyl ether is OK with me.

Jos

 

[Chris Murphy]

Well,if you say so Chris, I'll take your word for it, it 's been a long time since I had chemistry lessons at school. The only thing I seem to remember is that di- methyl ether is CH3 - O - CH3 and di-ethyl ether is
CH3 - CH2- O- CH2 - CH3 . Bottomline is that the product we all are referring to is the stuff used as an anaesthetic in the old days but then again , if you say it is di-ethyl ether is OK with me.

Jos

Quite right too-methyl ether is the formula you state....but there are a whole range of ethers-and for the purposes of model diesels there is only one that works-good old diethyl ether-formerly used as an anaesthetic-but also widely used still as a solvent in organic chemistry and in some industrial applications. Much of my university research work-in chemistry-involved very unstable organic syntheses which had to be carried out in anhydrous ether, so diethyl ether was virtually a daily companion for many years [we used to get it in in 200 litre drums for the lower grades...so called 'solvent ether'-the stuff I used was at the other end of the scale-spectral grade-extremely pure]

To make the point about the importance of getting your terms right-consider a simple analagous example....ethyl alcohol will make you happy....and if overdone...slightly ill.....methyl alcohol will make you blind...and if overdone...deceased in fairly short order...woe betide him who confuses the two...