compression release

[motor_head]

how exactly does a briggs compression release work i just can't figure it out. i seen the inside of many briggs and haven't seen anything that would hold a valve open on any of them

 

[EagleTalons]

One tappet is a little bit longer than the other to hold the valve open longer.

 

[motor_head]

so is it open just enough longer that it only makes a difference at low rpms or how does it "disengage"

 

[Thunderbird SC]

I've seen a few that have a crescent weight attached to the cam which is controlled by a spring. At low rpm the centrifugal force is low and the weight/fulcrum moves something to hold a valve open a bit on the compression TDC to release a bit of compression. The pic i have here is a similar version. Mine had a long weight that when up to idle speed the weight was cradled in a lip/rim the ran the was just shy of the cams teeth. I think the one I had was a safer version since the cam's lip/rim held the forces during higher rpm.

 

[Russ2251]

how exactly does a briggs compression release work i just can't figure it out. i seen the inside of many briggs and haven't seen anything that would hold a valve open on any of them

It's in camshaft profile.
"Easy Spin" is valve overlap and is easily observable. Exhaust and intake valves, for a very short time, are open at the same time which makes it easier to pull past the compression stroke.
It's removal will not increase power, but instead will make it more difficult to start.
The larger engines (as above) use a centrifugal/mechanical means of release.
The older engines used a manual release.

One tappet is a little bit longer...

Shouldn't be. Is only coincidence if it is. There is a cold setting (lash) which compensates for tiny variances in tappet lengths.
The two tappets are, essentially, identical. Part number is the same for both.