PASCO SE-8575 VISIBLE STIRLING ENGINE - Manual (Page 12)

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The Visible Stirling Engine 012-06055A
®
Maintenance
The PASCO Visible Stirling Engine SE-8575 is a delicate
apparatus. Treat it like a fine piece of laboratory equip-
ment and it will last a very long time.
Maximum Operating Temperature
The engine is made for intermittent use with a maximum
operating temperature of 100°C (212°F).
For Intermittent Use Only
➤ IMPORTANT: The PASCO SE-8575 Stirling
Engine is not made for continuous use.
It may be tempting to find a source of waste heat and let
the engine run continuously. Do NOT do this!
• The piston has a limited life time. While it should
last for years with occasional use, it will only last
for about 6 weeks running 24 hours a day.
• To extend the life of the engine, do not exceed its
maximum operating temperature. Do not run the
engine on heat sources other than hot water.
Non-Acceptable Heat Sources
➤ IMPORTANT: Do NOT heat the engine using
any type of flame!
The SE-8575 will indeed run very fast on the heat from a
candle flame, but you will exceed the maximum tempera-
tures of the materials in the engine and ruin it.
If you use a burner to heat the water, put the engine on
top of the water after the burner is shut off.
Running the engine on top of a lamp or a similar heat
source is likely to raise the temperature of the acrylic
above its yield temperature and ruin the engine.
DO NOT USE LIQUID NITROGEN!
➤ IMPORTANT: Liquid nitrogen is far too cold
for this engine and very likely will break it. Dry ice
would probably be okay but has not been tested.
A good cooling source is “freeze spray”. This is sold in
an aerosol can at Radio Shack and other electronics
supply stores. It’s a lot of fun to make the engine appear
to run on “nothing”.
DO NOT OIL THE BEARINGS!
During the development of this engine, many different
lubricants were tried in an effort to improve performance.
None of them improved performance at all, and most of
them made the engine run less well or not at all.
All the bearing surfaces contain Teflon. It is unlikely that
any lubricant you might use would improve performance.
To Remove Oil:
Oiling the engine will probably degrade performance or
cause the engine to quit. Use a TINY drop of WD-40 (a
very light dispersant petroleum based product) to clean
off the oil. Be careful to keep the oil from running over
the red anodized surface as it will stain the anodizing.
KEEP THE ENGINE DRY!
After running the engine, make sure it is completely dry
before putting it away. The metal ring that holds the blue
plate on the bottom of the engine in place is made of a
stainless steel alloy that contains some iron. It can rust if
not put away dry. Towel dry the engine carefully before
you put it away. Blow drying it is also a good idea.
Most Common Reason for Engine Failure
• The most common reason for the engine failing to run
is inadequate thermal transfer. If the engine won’t run
try putting about an inch of water in a coffee mug and
microwaving it until it is boiling vigorously!
• Remove the mug from the oven and place the engine
on top of the boiling water, wait 15 seconds, and turn
the prop the direction indicated on the instruction label
for “hot on the bottom.” The engine should start
quickly and run rapidly.
➤ NOTE: Boiling water is dangerous. Handle
with care!
If the engine still does not work or runs very slowly, refer
to the Troubleshooting section.