Kshansen,
 
No offense taken at any comments. I really appreciate everyone who sticks with me on this.
 
I don't think I was the one that said the ACR was after TDC, but if I did, it was a mistake.
 
I made a comment about crank and cam rotation as I was concerned about the cam lobe orientation.  I noticed that the shaft is splined but I am overthinking things.  Just to verify, the exhaust and intake are more than 90 degrees apart at their maximum opening?
 
Before I took the engine apart this is what I noticed.
1. i took out the spark plug and marked the flywheel orientations for TDC and BDC
2. valve clearances were way too wide.  I corrected that by adjusting slightly after TDC on compression/power stroke
3. I looked at the action of the exhaust and intake valve.  The exhaust opened pretty close to BDC and closed at TDC
4. The intake seemed to start open movement after TDC ( should have noted degrees)
5. It finished closing I beieve after BDC, maybe not too much after
Now here is what I think I saw that you find confusing...
6. The gap that was set for the intake didn't seem to appear until much later in the compression stroke.  No rattle, couldn't get a feeler gauge in...
7. The starter couldn't make it to TDC on compression.  maybe got hung up 20 degrees or less before that point.
 
I tried to help the starter with one hand... other was on the key and I couldn't do it.  with two hands not too difficult to put palms on the flywheel and turn it.
 

I'll try to back off here a bit as my thoughts are only based on basic engine functions. AVB has a much better incite into the specifics of this engine. To be totally honest the only time I ever touched a wrench to an overhead valve Briggs other than to install a couple new ones in my snow blowers was several years ago. That was when i adjusted valves on a rider mower at work that we originally thought had a bad starter because it would lock up while trying to start. Set valves and it would crank like crazy again!
 
Now give me a 16 cylinder Diesel and I'd feel right at home!

Stop overthinking this. When the piston is at tdc, the upper limit of it's travel. both lifters should be riding on the cam lobes. That is, the exhaust is closing as the intake is opening.

took the starter off and checked its internals.  Pinion gear and shaft are now clean and sliding freely, no broken magnets, commutator is clean and brushes look solid. Now signs of burning or discoloration.  Not sure how else I can evaluate a starter.   Going to give it a key turn after I get some oil in the motor.
 
Previous owner was jumping the starter directly on the post.  He must not have noticed that the 20 amp fuse between the igntion and battery was blown.

I removed the cam and it was fine.  the ACR was complete and working fine.
 
I put the motor back together, and installed the starter.
 
Same situation.  The motor spins until it sees compression and stops.  I marked the flywheel and it stops about 45 degrees before TDC.  That looks to be about the same place the intake valve stops moving from the ACR.
 
I jumpered right to the starter lug.  no better.

ordered a new starter from Amazon last night.  will arrive tomorrow
 

I was just at the big box store and I looked at the mowers outside.  similar HP briggs and stratton.  Starter looks the same.  I tried to turn the motor with my palms on the flywheel screen like I did for my motor.  Just as much if not more resistance on this one.  I think the starter will be the fix.  If it does, the old starter will meet my sledge hammer so nobody ever thinks it is worthy of another crank.
 
All this is based on the starter really being the same.  The battery was under the seat on this model and might have been a little beefier... hard to say.  I didn't check CCA.
 
Also, before I ordered the starter, I read a review on amazon where the reviewer said that even though his starter engaged and would spin, it didn't have the strength to crank the motor.   the new starter fixed that.  Good enough for me.

Any idea of the compression(tester) when it hits that spot?
Did you use just the battery or the jump pack?

A final update on this long thread.
 
The mower started to crank normally and almost without any fix.  The only thing I did was put the jumper cables and a jump pack on the cables at the same time to try and maximize the contact for current to flow.  Starter cranked quickly and compression rose to 90-100 psi.  Amazing.
 
After that I connected only a jump pack and it still worked.
 
Since then I bought a new battery, got it to fire up, adjusted the PTO and verified that it could move in forward and reverse.  I will take it for a longer run later today, but it appears to be working pretty well.  
 
Thanks to everyone for their help.  I wish I could share a good reason why I had so much trouble.