Small Engines (Lawn Mowers, etc.): lawnboy won t start, throttle linkage, throttle plate

Question
The lawnboy is a two stroke (no valves) I will try to get a compression gage. I will also try to find out why the throttle plate is normally held open by a small tortion spring  I assume it has always been that way.
Followup To

Question -
Have tried both sqiuirting gas using the primer and ether. into the carb. Still no action. The lawnboy has only one flapper in the carb body I believe it to be the throttle plate. it is attached to the throttle linkage and the airvane which is controlled by the fins on the flywheel I dont believe the older lawnboys had a choke
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Followup To

Question -
Have an older lawnboy pushmower that will not start this year   Gas primer works well. lots of spark at the plug. clean air filter new gas, reset magneto gap. removed flywheel to check for sheared key. Compression seems good. Blade is secure. Using  large airdrill to crank as arm is worn out. Should throttle plate be open or closed at rest? Thanks for your help.

Answer -
Hiya Harry
You shouldn't be able to "see" the throttle plate.  Should be the choke plate you're looking at, and it should be closed.  Try this, squirt a bit of gas into the carb, if it cranks, you have a fuel delivery problem.
1-Float is stuck, or bowl is full of water
2-Gas tank dirty, pickup is clogged (or fuel filter)
3-Carb is gummed up and idle jet is clogged (rebuild)
Lemme know what you find!

Answer -
Got it Harry- right, some models with primer bulbs have no choke plate.  If you squirt gas directly into it, and your spark and key is good that really only leaves a bad valve as a reason NOT to fire.  Generally this will be a slightly burned exhaust valve.  Can you do a compression test with a tester? should get at least 85psi  90-100 is better.  (spin with the drill for about three seconds).
Hmm- does the throttle control show a start position?  PLate should be closed.  Back from Vac- so responces will be faster (sorry bout that)
Lemme know
CYA

Answer
Hi Harry-
Being its a two-stroke, one thing you gotta check is the exhaust.
Two strokes (especially older ones) develop soot build-up in their exhaust.  When enough accumulates to develop back-pressure, the engine will not fire no matter what!
Disassemble the exhaust and clean it all up (be careful not to scratch the piston- you can actually reach it with the exhaust removed)
Lemme know!