Small Engines (Lawn Mowers, etc.): Briggs compression relief, internal resistance, clearnce

Question
I have a 20.5 hp twin flat head Briggs, M# 461777, T# 0137E1,C# 9710285. Please tell me if this engine does or does not have a compression relief.I have been told it definitely "does" and it definitely "does not". I have read many Q&A's on this subject and none have cleared this up for me. I have narrowed my hard starting problem down to starter or internal compression relief. I don't want to tear it down to grind the valves for less lash or replace the cam if it does not have a relief system.

Answer
The compression release is a mechanical compression release ground on the exhaust lobe of the camshaft...not servicable unless you replace the cam...I have never replace a cam in a 46 cubic inch block.

The valves are easy to check but most hard starting problems due to valves are caused by too much valve clearance...only happens if you grind too much off the valve stem.  Under normal conditions the valve clearnce decreases and does not increase.

Battery...it is good and have you had it load tested?

Cables and connections.  Have the connections be disconnected and cleaned with a wirebrush...battery terminals and cable ends.  What about the ground connection?

Did you measure the voltage drop across the positive and negative cable?  I have had two issues where the internal resistance of the cable would not provide sufficient current flow to turn the starter.  Rare but it does happen and more prone on older cables.  You can google "how to measue voltage drop' and find several articles.

Is there a local auto electric shop who can test the starter torque and current draw?

Let me know.
Eric