little machine shop walking beam engine

[lseguine]

hi to all.

I was given a kit of the walking beam engine from the little machine shop web site. i machined it according to the blue prints with in the tolerances of my tools. i did not do the fly wheel exactly to the blue prints by not cutting the holes in the web section , figuresd more weight would run smother. but applying the heat source the engin didn't even try to run. What might i look at to try and get this thing to at least to try to run. Is it possable the flywheel is to heavy? how tight must the power piston fight the power cylender? i laped the piston with flitz polish untill iy just slid freely into the power cylinder.

any help on getting this thing to run would be greatly appreciated.

Thanks
Larry in alaska

[Cartech]

How much friction do you have? Everything must move very free and air leaks kept to a minimun. You probably already know all that though. Double check your phase (90 degrees) between the piston and displacer. I have read that it's best to error by too heavy a flywheel than too light. Too light and it won't run, too heavy and it's slow. Does it spin better when hot? If it spins many more revolutions by hand hot than cold, your at least getting close. I hope that helps...

[lseguine]

thanks for the input

friction seems to be very little, the weight of the crank can rotate the flywheel to the bottom of its stroke. the phase angle is 90 degrees clearly. the engin rotates about the same hot or cold. it relly has me stumped. i look at othe engins that look a lot more crudly built that are running and can't figure out why this one just doesn't even seem to try????

any other sugestions
larry in alaska

[SScandizzo]

Hi Larry,

Without any heat applied, if you flick the flywheel either direction, it should spin about a quarter turn or so and then bounce back to its resting position. If the flywheel simply spins without rebounding, there is a reasonable chance that the system is not air tight. Try disconnecting the rocking arm from the power piston conrod; does the power piston move when you turn the flywheel? If it does not, there is either too much friction or an air leak. Sometimes a drop or two of machine oil will seal this leak (temporarily) but be sure your kit's instructions allow for oil (sometimes adding oil to Stirling can only bind the cylinders). Check for little bubbles that would indicate a leak, too. Be sure to test all seams, the displacer itself must be airtight, and both the power piston side as well as the displacer bushing.

What ever you do, don't apply too much heat. It might get the engine to run for a few moments, but ultimately it most likely do damage. If necessary, put it away for a few days and come back later. You might see it slightly differently.

Hopefully, you've gained some appreciation for the crude but functioning engines you've seen here and other sites. There seems to still be a bit of "magic" left in some technologies which I believe makes Stirlings just a bit more appealing. Also, don't hesitate to keep asking questions and possibly posting pictures!

Best of Luck,

Stefan

[lseguine]

http://www.stirlingengine.com/file-stor ... ile_id=260

here is a pic of my engine???? i hope

larry in alaska[/img]

[lseguine]

http://www.stirlingengine.com/file-stor ... ion_id=299

here is a pic of the cams. i think i'm getting this figured out i think. [/img]

[lseguine]

http://www.stirlingengine.com/file-stor ... ion_id=303

here is a view of the power piston top of stroke.[/img]

[SScandizzo]

Hi Larry,

The pictures came through just fine. I can't see anything obvious from the images, so I'm going to have to depend on your descriptions of how the engine "feels". Check the items I mentioned before and let us know what you observe.

-Stefan