Flame eater questions

[lazylathe]

Hi All,

I recently picked this engine up on fleabay for a steal!

It seems to be in pretty good condition, jut needs a good cleaning and polish.

I am having a hell of a time trying to get it to run! :-\
The original spring steel valve(?) did not cover the whole inlet port so i made a new one that fits a lot better and actually gives the engine
a bit of compression.

It has a graphite piston.
The only ball bearing is the one that runs on the cam.

I am wondering if the return springs tension is too high.
It takes a lot to spin it over.

I have tried lots of different flames, sizes and positions but no luck.
I have also read through all the builds here and tried a few of the mentioned fixes to no avail...

Any help would be greatly appreciated!!
My fingers are aching from flicking over the flywheel for the past 2 hours....

Andrew

 

[Stan]

Lap the valve plate to the cylinder. Than has to be a vacuum tight seal. It also has to turn over quite freely.

 

[lazylathe]

Thanks Stan.

I have lapped the valve plate and it seems to be a tight seal.
It makes that sucking sound now.
But still no luck with getting it to run.

I have tried varying the spring tension and it spins more freely now.
Will keep trying to get it to run!

Andrew

 

[portlandron]

The spring looks stronger then the spring on the one I built. Try using a spring from a retractable ball point pen.

 

[90LX_Notch]

Andrew,

Things to consider:
Are you sure you are turning it over in the correct direction?
Preheat the cylinder with a propane torch.
Smear some oil around the port face to get a better seal.
Use thinner material for the valve. On my Poppin I used .002 shim stock and made a .005 helper "spring" out of shim stock. That helped immensely.

Bob

 

[doc1955]

The spring looks to be way to strong you want a sping that will just have enough strength to push the valve back. If you get compression you are turning it backwards.
Here is a video of my very first engine I built many years ago.
[ame=http://youtu.be/wQjcpS8pmAw]Engine Vacuum[/ame]

 

[pcw]

read the info on Jan Ridders site bout flame eaters:

http://heetgasmodelbouw.ridders.nu/Webpaginas/pagina_happer_inw_schuif/inw_schuif_frameset.htm

tons of info on them on there.
Pascal

 

[lazylathe]

Thanks for all the replies and help!

1- I will try a different spring for tension. Will need to make an adjustable collar to increase or decrease tension.
2-Turning over in the correct direction? I was turning the flywheel anti clockwise when looking at the flywheel. The same was doc1955 does in his video. Some other directions say to turn it clockwise??
3- Have not tried to preheat the cylinder. Another one for tonight.
4- Will use some oil around port face.
5- Will try to find some thinner material for the valve. Would aluminium can material work in a pinch?

Have read all of Jan Ridders site info, he has a wealth of info there! Good stuff!

Doc1955 says if i get compression i am turning it backwards. Will try the other way tonight. Since i made the new valve last night when i turn it anti-clockwise it make the sucking noise. It does not do this going clockwise.
So would that mean that my one runs in a clockwise direction?

I also think i need to make a proper burner. On Jan's site he says the wick needs to touch the cylinder.
At the moment i am using another burner from one of my other Stirling engines. It just has a large flame.
Could that also be one of the problems?

I will try and make a spring at work out of some thinner stainless steel wire.

More updates tonight!

Andrew

 

[lazylathe]

Found some more info with a bit of help from another site!


I was still a bit unsure of what i had bought...
A little research gave me some insight!

It appears to be from around 1986!
Could be one of the first prototypes as mentioned here about half way down:
http://www.craftsmanshipmuseum.com/other.htm

There are some differences though...
Mine does not have the oil holes drilled into the crankshaft supports.
The cam follower is a different design.
And the valve it had on when it arrived looked home made. I changed it for a better fitting one.
The base is exactly the same minus the little plaque.



Andrew

 

[Stan]

To determine the correct rotation. The valve should just start to open when the piston starts it's down stroke.

Flame position is critical. Small changes in a small area vary the speed. Outside of that area, it doesn't run. When I made a new burner for mine, of that basic design, it took me days to get it running on the new burner but would work fine with the old burner.

 

[lazylathe]

It looks like this guy is going to keep me busy for a while...

When it runs it should be a lot of fun!

I contacted PM Research to ask them if they knew anything about the engine.
Since it was made before the new owners took over they just recommended i buy a whole pile of accessories and see if that helps.

I will keep trying different options and see what happens!

Andrew

 

[mklotz]

If the cylinder is too cool, it will 'quench' the gas before the valve can close. This means that it will not develop a sufficient vacuum to allow atmospheric pressure to provide a good power stroke. On mine I 'toast' the cylinders for a minute or two over the alcohol flame before trying to start them.

 

[lazylathe]

Thanks Marv, i will also try that.

Had some more contact with PM Research and now have a few more answers!
They have never seen one like mine before.
It is missing bits that the prototypes have so may be an early prototype before going to production!

Mine is missing the valve, a brass plate that slides over the port that is attached to the valve guide.
The original burner is also absent.

I have ordered some bits and hope to have it working soon!!

Andrew

 

[90LX_Notch]

Andrew,

Just be careful about changing too many things at once. If all it is, is that you're turning it over wrong, the other changes could possibly have a detrimental effect. Go about it systematically.

If it's timed correctly, and the piston as well as the vlave, are sealing properly it should run as long as it is sucking in the flame.


Bob

 

[lazylathe]

Hi Bob,

Thanks for the tip!
I will wait for the original parts to come in and put them in place.
If it runs with them i will be a happy camper!

Still need to figure out the timing thing..

Andrew

 

[jonesie]

i would make sure you are turning it in the right direction, the one i build turns clockwise or top of flywheel is going away from the cylinder as i think most do. mine is like marvs the cylinder needs to be good and warm before it will run then it runs real good, flame location is also real touchy. good luck jonesie

 

[kustomkb]

Here is a video of mine (Duclos), they look similar, it may be of some help; (or I can just show off my first engine ;D);

[ame]http://www.youtube.com/watch?v=fumWEZ3ZQ38[/ame]

 

[lazylathe]

I have watched your video many times Kevin!!
It makes me have some hope that it will finally just run.

I may spend some time taking it all apart again and giving it a good polish! ;D
I like shiny engines!!!

Andrew

 

[arnoldb]

Andrew, like Marv and others said, my "Little Blazer" also needs a bit of pre-heating.

The flame position is also critical, and there must be no draught around; don't even breathe too hard near it.

Some of the concerns that jump to mind from the photos and comments you posted:
* The scoring marks around the valve at the top and bottom edges - that would seem to indicate burrs on the valve plate, and would add a lot of friction, as well as prevent a good seal
* The spring looks to be overkill - the lighter the spring you can use, the better.
* You said you felt "compression" when turning over - that would actually be vacuum in an engine like this. That's a good sign - it should give resistance to turning in one direction of flywheel rotation, and nearly none in the other direction. The direction in which you get the least resistance is the direction the flywheel must run in, and you need to flick it in. (And develop a callous on your finger in the process )
* Aluminium for the valve - I don't think it will work very well, as aluminium is not very springy, and at heat softens rapidly. The valve on an engine like this gets surprisingly hot while running. I might be completely wrong though.

I have a hunch that the engines built to Phil Duclos's design has one distinct advantage. Phil used a separate valve port plate and spring, and if one didn't solder them together (Like I did :), the valve would seal a lot better. With a single-unit plate like the one you show on your engine, the entire piece of plate has to sit perfectly flat on the port face. With Phil's way (as on Kevin's engine) the port plate is loose, and will find it's own equilibrium on the port face. Also, once the vacuum starts to form on the power stroke, the valve plate will seal more easily - getting sucked down on the port face.

I had some issues with mine. After building it, it started right up and ran, but after a couple of hours of intermittent running it became obstinate. I eventually figured out that the entire frame and everything got so hot that the oil I used on the main bearing bushes and so on started breaking down from the heat and became sticky. So I gave it a good clean to remove all traces of oil, and used a liberal amount of graphite powder to lubricate all the moving parts. Works a lot better now, and I run it regularly; in fact I think this engine of mine has the most running hours on it of all my engines.

The main thing would be to get as little friction as possible on all the bearing surfaces, the valve spring (both the spring on the valve shaft and the valve bearing down on the port face) needs to be as light as possible, and the engine must have good vacuum. And play around with the flame position. These engines can be very tricky, but, like you said, they are a lot of fun to run once they get going.

And like Bob said - work at it systematically; don't go changing a lot of things at once. These engines are a true trial of patience ;D

Regards, Arnold

 

[lazylathe]

Thanks for all the tips Arnold!!!

I have some original spares on order and they will replace the valve plate i made plus a brass valve that fits into the actual plate. Hopefully this will give a good seal.
The spring is original to the model, so i will keep it like it is for the moment.
Also a burner that has the correct wick and height is on order so that should help a lot too!
They are also sending me the owners manual for this engine for free, a nice surprise!

Once all the parts are replaced i will hopefully have some more luck!
Will keep updating on progress once the parts are installed!

Andrew