Gift of Model Plane Engines

[ShopShoe]

Several weeks ago I got a call from my favorite Uncle who has been flying model planes since the 1940s.

"Would you be interested in some model airplane engines? It breaks my heart but my hands have so much arthritis that I can't handle the small parts any more. If you want some, I'll send them right away. Do whatever you want. Melt them down if you want. I just have to say goodbye to a lot of my stuff."

The picture shows what was in the box he sent. Some of these are frozen. There are no plugs in any of them. Now that summer is coming I am wanting to see if I can maybe run one or two of them on the bench.

I would like to clean up and display something as well. I think the "Peace Pipe" muffler (lower right) is pretty cool by itself.

Having never done anything with small engines like this, I don't know what to do. I am sure there is a hobby store near me that may be able to help me with parts and fuel. Can anyone suggest what I want to check and what I need to buy?

ShopShoe

 

[lohring]

The place to start is the Model Engine Collectors Association. Another great site that is no longer being updated is http://modelenginenews.org/

Lohring Miller

 

[deverett]

A very generous gift from your uncle.

The fuel would probably have contained castor oil and when this burns in the engine, if forms a varnish-like film - usually seen as a brown coating on the outside if fuel has spilt and burnt with the heat of the engine running. With the engines standing for a long time, it could well be that this varnish is the problem.

Perhaps methylated spirits or acetone (If no plastic parts) poured into the cylinder and crankcase and left for a day or so before trying to turn the engines would be a starting point.

Dave
The Emerald Isle

 

[footloose]

I have recovered many glow and diesel aeroplane engines that have been seized from standing with castor based fuels.
The method I use, which has never failed to work, is to use an electric heat gun to get the engines hot enough to soften the age hardened castor oil. I use thick riggers gloves to keep my hands from getting burnt and when the engine is good and hot I cautiously try turning the shaft just with my fingers, when it starts to move I squirt some light machine oil in the exhaust and inlet ports. I watch out for the fumes and smoke, the engine is very hot, remember. Very soon the engine will turn over freely. I let it cool, a squirt some fuel mixture in the ports, turn it over until it is perfectly free, then mount it up and run it.

Hope this helps you, Bert

 

[gus]

I have recovered many glow and diesel aeroplane engines that have been seized from standing with castor based fuels.
The method I use, which has never failed to work, is to use an electric heat gun to get the engines hot enough to soften the age hardened castor oil. I use thick riggers gloves to keep my hands from getting burnt and when the engine is good and hot I cautiously try turning the shaft just with my fingers, when it starts to move I squirt some light machine oil in the exhaust and inlet ports. I watch out for the fumes and smoke, the engine is very hot, remember. Very soon the engine will turn over freely. I let it cool, a squirt some fuel mixture in the ports, turn it over until it is perfectly free, then mount it up and run it.

Hope this helps you, Bert

Hi Bert,

Timely advice. I have six DIY Balsa Planes built 12 years ago. By now they may have seized. Will check tonite.

 

[goldstar31]

I quite agree about fact and a that heated castor oil will and does esterify into a sort of varnish but I'd be loathe to heat the lot up.

Probably, nothing more is required than dunking the engine in something like nail varnish remover which probably contains acetone with a small amount of oil.

What has to be remembered is that castor oil is one of the main constituents in oil based paints. We used to make and sell a mixture of paraffin wax and acetone to remove paint. Certainly avoid anything with caustic soda which goes into present paint and varnish removers. Naturally there are other chemicals but nail varnish remover is fairly easy to obtain.

Seized cast iron engines? Coca Cola which contains phosphoric acid!

Cheers

Norman

 

[gus]

I quite agree about fact and a that heated castor oil will and does esterify into a sort of varnish but I'd be loathe to heat the lot up.

Probably, nothing more is required than dunking the engine in something like nail varnish remover which probably contains acetone with a small amount of oil.

What has to be remembered is that castor oil is one of the main constituents in oil based paints. We used to make and sell a mixture of paraffin wax and acetone to remove paint. Certainly avoid anything with caustic soda which goes into present paint and varnish removers. Naturally there are other chemicals but nail varnish remover is fairly easy to obtain.

Seized cast iron engines? Coca Cola which contains phosphoric acid!

Cheers

Norman

Hi Norman,

Good advice. How about thinner?

 

[goldstar31]

Hi Gus!

Using the word 'thinners' conjures up all sorts of liquids and therefore, I quoted something which was easily obtainable, pretty safe and reasonably cheap.

The history of using acetone- part of nail varnish remover was also used as paint remover by one of the largest paint manufacturers- internationally. A bit of misnomer as International Paints ltd was in direct opposition as it was a subsidiary of British Paints- both Tyneside companies.

I hope that this helps.

Meantime, I'm having a break from 'the office' and heading to HK and then onto Fiji.

Regards

Norman

 

[ShopShoe]

Thank you everyone. I'll see what I can do in the next few weeks.

--ShopShoe

 

[tornitore45]

Whatever you do, resist the temptation to disassemble them.
They are all seated and run in. Reassembling will disturb that fine equilibrium.

Look like a start of an enviable collection.

 

[footloose]

Please let us know how you get on, I have never had any success with soaking seized engines but I have an open mind on the subject.
I can't see any objection to heating them up, they don't stay at room temperature when you run them.

Bert

 

[Rndmann9]

Prob not seized. The fuel they use has caster oil in it mixed with nitro methane. It gets sticky over time. I dis assemble them all the time really interesting how they work with a hollow crank. Basically miniature two stroke engines. I have a bunch of them. The one on the left is for a car. I have two cars and a couple planes.

 

[Rndmann9]

If you do take it apart just make sure the piston is back in the same orientation as before. The engines are sleeved like a diesel in fact they kind of run like one with the glow plug in all. The sleeve has a pin on one side at the top of the head so it's kind of hard to put it in backwards. It's only about three parts to it. Case,shaft, piston sleeve and piston assembly. Bearings will stay in the casing. You would have to heat it in the oven to get those to drop out.

 

[ShopShoe]

Thanks for the additional information. I haven't had much shop time lately and some car, yard, and house projects have taken more time that I would have liked. I will post more when I get a chance to play with the engines.

 

[Rndmann9]

Just let me know if you have any questions. I'll answer what I can. I have one that's taken apart somewhere I'll post some pics when I find it.

 

[Rndmann9]

Found the engine I was looking for. Circles are the tiny alignment pin I mentioned. For the sleeve and crank case

 

[Rndmann9]

I usually use a scribe to make a mark on the piston head to indicate which side goes toward the pin. Other wise it's a 50/50 chance of getting it wrong. If you did it wrong it would be noticibly tight since they are worn in to each other. To remove the piston you have to push the sleeve out first. That gives enough play to move the push rod off its pin on the crank.

 

[Rndmann9]

This was another car motor. Biggest differences are the engine mounts and the number of heat disapating fins on the crank case for car vs airplane. Planes moving through the air don't need as much to get rid of excess heat as the cars.