DEK 11 rebuild (Honda gx340 clone, I think)

bertsmobile1

Lawn Royalty
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Nov 29, 2014
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I re-gapped the valves and coil to spec and tried compression test again. I got between 30 and 32 psi.

Like a lot of things, compression readings are not as simple as it looks.
On a small engine the compression tester must occupy all of the volume usually taken up by the spark plug .
Thus to get an accurate number you need a variety of ends.
If you are working on a multicylinder engine not so much of a problem as you are generally looking for differences between individual cylinders.
On a single cylinder engine then you are looking at changes over time , using the same tester.
On small capacity cylinders this is even worse as the volume of the spark plug hole can often be greater than the volume of the entire combustion chamber.
If you really only had 32 psi the engine will not fire.
 
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