Small engine shaking too much when running, Why?

You can check as in this pic. Just fine lines cast in.

HS40 timing marks.jpg

David
 
how do you suppose timing makes a one cyl eng shake that bad and still start and run good?
 
cg285 said:
how do you suppose timing makes a one cyl eng shake that bad and still start and run good?
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I don't. The engine is either running as designed or some sort of rotating mass is way off. I can't think of many possibilities.

David
 
GoceKU said:
As i've stated earlier, i've been thru every system on this engine and set it as per the service manuel, only ignition timing is untouched, i may need to make a jig to hold a dial indicator in the spark plug hole to time it as per the manuel.
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back in the points days of dirt bikes i had a di that screwed into the spark plug hole. i don't think that is your problem tho'.
among other things i'm an onan dealer and back in the points days timing was with the point gap - ie point gap correct - ship it
 
It has nothing to do with timing. It's a single cylinder engine......vibration is par for the course. Unless it has a counter revolving weight, it will shake. The lighter it is, the worse it will shake.
To dampen the vibes, you must add mass. The pipe frame it sets on, is amplifying the vibrations. The farthest point on the frame away from the origin of the vibration will be the worst, because that is usually where the least mass is.
Ask any Harley rider why they fill their handlebars with silicone or lead shot.

Put a 1" thick plate between the motor and the frame to add mass, it won't go anywhere.
 
I'm cheapie here ..
put it in a plastic dishpan type container, add cement , wait, use :>)
course u could makeup a perfect container with a few 2x4s , but like I said ...cheapie...
....Make sure those rubber eng mounts are not too soft/loose? cuz with that mass on the frame, they're going to get a workout.
 
i wonder how many of those they sold that you had to add weights to to keep the power cord in.
 
cg285 said:
i wonder how many of those they sold that you had to add weights to to keep the power cord in.
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I'm not sure how many they sold, but i think they are rare, i've only seen two listed for sale on the internet, other thing that's strange on the Tecumseh engine it also had the FIAT, logo not sure why.
DSC_0005.JPG
 
Many models like this have them mounted on isolators, rubber or springs . The frame may have had the rubber type and were drug off or worn off or removed, I'd mount it to two 2x4s with compression springs between the wood and frame. It may shake but it won't or shouldn't move. If the plugs fall out it may need a new outlet.
 
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