Borat, did the machine reference above match your machine?
>>>No oil fill holes or valves on this engine.
It’s got a port cover, rings and head gasket.
Friiy,
>>>That's why Most good Leak down testers have a built on regulator (not adjustable) and Calibrated feed inlet that only allows (X) cubic feet per minute of flow..
Right, so I don’t know why you mention the CFI unless you have some weird set of gages. ?? Why are you dumping in 100psi on a small engine? It will only make the test setup harder and maybe hurt yourself with piston and flywheel turning under pressure that great.
The small engine leak down gages are low pressure sourced from a regulated tank (required and standard on most compressors). The low psi (15) on these gages are all that’s needed and work fine across small engines without knowing the CFM. You don’t need to know for these gages. It’s taken care of.
Friiy:
>>>The Compression gauge will tell you what compression the motor will make in typical attempt to start... If it will not make compression, it will not start or will be hard to start. (isn't that what most people are looking for?)... Your calibrated arm pulls the same every time (until tired)...
This isn’t a plane or car engine. At least that I ever heard of or read no one ever uses a compression gage related to starting pressure values on a small engine 5-13hp. They are used to determine the general health of the components related to compression on the power stroke. Compression gage can’t do that especially in 4 strokes where they can only give you very limited info at best.
Some L-head engines and it’s very rare will allow a full reading on the compression stroke so for them a valid reading. I test lots of L-head 4 strokes but not 2 stroke where the info would be less with a leak down than a 4 stroke but still more useful than a compression test i.e. port covers, reed valves, head, rings and other types of intake exhaust mechanisms.
Wicked low compression test values are one of the few places a compression test is useful.
