New Cam-Release on 19 hp B&S Intek

Couple additions. My charger says its good for 10 seconds. I used it for 2-3 secs maybe with no plug to make sure the engine would spin so almost no load on it. Trying with the plug in, I Only used it for 1-2 secs only to get to the compression stroke. So, with some more hand testing I got to where I finally got confidence the cam et al was doing its thing with the release. To my mind it is s pretty subtle feel, but fairly obvious once you kind of figure where it occurs on the stroke. At that point I got to reinstalling the engine. I was kind of surprised with the battery in the mower. Had not run since last spring so I put on the charger while I bolted in the engine. By the time I got the 4 mount bolts in, the charger showed almost a full charge. The new battery was installed as a 'fix' by a supposed expert when the machine died last spring, along with a new starter motor. The guy got paid by my wife's sister and was a supposed expert on these type mowers. He told her he could not diagnose the engine problem. Some expert. Anyway, hooked up the battery, no plug to make sure the battery and such was good, spun like a banshee. Put the plug in, cranked good so I smiled knowing the release was working. Hooked up the wiring, put in some gas, vroom, vroom. Nice and smooth. We didn't take the mower out so I hope the valve adjustment is good, I assume I got that right but this being my first Intek cam job, I felt pretty good. One question I still have. Why does B&S use that somewhat delicate widget device for the release? I get the idea of why its there, but the little parts and their (to me anyway) delicate nature just look like something that could be done in a more robust manner. I do not have a better idea but I am not an engine designer either. Do other engine makers have other systems for a compression release?
 
Hello Bob,

Unfortunately, the compression release mechanisms are not that robust on purpose. The light design makes sure there is not excessive rotational force when the camshaft is turning at high RPM. A camshaft rotates at half the speed of the crankshaft.

The purpose of the compression release mechanism is to squeeze higher horsepower/ torque out of these small engines. Without a compression release, the starter would need to be twice the current size.

I think engineers are always coming up with ways to push smaller engines to the point of self-destruction.
 
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