Join Date: Oct 2018
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Outline for High School class on small engines
Day 1: Welcome to Small Engines 401 for fourth year students and any other year students interested in learning about small engines, their repair and maintenance.
Today we're going to learn about carburetor repair and maintenance.
To avoid most carb problems, you put Stabil in your gas can, what's it called?
Yes, Stabil - it's a fuel stabilizer for all gasoline engines. What's it do?
Yeah, what's the problem with fuel these days? Does anybody know?
The ethanol in fuel goes bad in a month or two, particularly over the winter and then your mower won't start in the spring or your snow blower won't start when it first snows after the gasoline went bad in the gas tank during the long summer.
What's the problem with fuel these day?
(The ethanol in fuel goes bad after about 2 months.)
Yes and what's the effect on your machines like lawn mower, snow blowers and chain saws?
(They won't start)
Yes, they won't start. For the rest of the class period we're going to take carburetors apart and see what ethanol does to cause problems. (Write 'carburetor' on the board and underline the 'u' and say 'carb', 'er' spelled with a 'u', then circle the 'e' and say 'ay spelled with an 'e', 'tor'. This spelling will be on your test. Look at that weird spelling.
(As they leave at the end of the period, each student must spell the long version of 'carb' in order to get out of the class. Erase the board right before they leave after repeating the emphasis on the letters. It doesn't matter if they all hear the spelling over and over again as other students leave. It'll help them remember how to spell the word.)
We've gotten each of you a machine from the local metal recycling facility in town. Get your tool box out and take the top cover off and then the air cleaner. (supervise)
Now take your carb-er-ator with a 'u' and an 'e' off the machine (supervise).
Now put some rubber gloves on and take your carb-er-ator apart (supervise noting the crud and thick stuff found in specific carbs as the class progresses).
Day 2. Continue above until several problem examples have been found.
Day 3. Order parts to rebuild carbs by looking up the kits on-line using machine model numbers, etc, whatever is needed to get the kits ordered.
Day 4. Rebuild the carbs, whether they need it or not, with kits that were pre-ordered by the teacher.
Day 5. Re-assemble the machines and see that they run.
When the carb kits come in, the students get to keep them as reminders of what they learned. Look for other problems for week 2, 3 and 4 as you fix carbs.
Revise above to include gas and oil removal and disposal, on each of the machines before even taking the carbs off the machines. A lesson on oil comes to mind as there will surely be a lot of very black oil in the machines. Some will probably be overfilled. Watch for that specifically. Check the oil and fill the gasoline lesson would be good. Watch for bad smelling gas and let everybody smell it when it's found.
Just the above is enough to take you into weeks 2, 3 and possibly 4. Something on wrench and socket sizes would be good. Use rulers to show sizes marked on the tools.
Talk about oil types and what is appropriate for summer and winter use...