Four engine failures at nearly the same time

[Kansas kymco]

I should have said batteries. They would only last about 3 years. I'm now using the old AGM out of one of the Kymco scooter's I put a new battery in.

[Stig / Major Tom]

Update...
Karl never showed with his riding mower!!
Wife, daughter, dog and 2 neighbor kids looking at me (they came to my front door - and just stared) and back at the leaves...
So, I mowed the d___ed things.
Stig out....

The 45mph winds today has solved my leaf issue.....but not my neighbor's 😊
Stig

[CROSSBOLT]

The 45mph winds today has solved my leaf issue.....but not my neighbor's 😊
Stig

"But not my neighbor's" is a hoot!

[CROSSBOLT]

Update on #4: no compression on Briggs. Did initial teardown this afternoon. Clearance on valves nominal. Removed head. No burned valves, no hole in piston, bore looks good. No obvious reason for no compression.
Suggestions?

[Kansas kymco]

Update on #4: no compression on Briggs. Did initial teardown this afternoon. Clearance on valves nominal. Removed head. No burned valves, no hole in piston, bore looks good. No obvious reason for no compression.
Suggestions?

Could the cam have broke?

[CROSSBOLT]

Could the cam have broke?

The cam IS turning because the rockers do their thing in the correct sequence. However, I will check to see if valve timing is correct.
I'm thinking broken rings as a possibility but the cylinder looks to good for that. Stuck rings may be more likely than broken. Your idea has merit and I thank you for it!

[Kansas kymco]

The cam IS turning because the rockers do their thing in the correct sequence. However, I will check to see if valve timing is correct.
I'm thinking broken rings as a possibility but the cylinder looks to good for that. Stuck rings may be more likely than broken. Your idea has merit and I thank you for it!

If the valve timing was off wouldn't the valves hit the piston? I don't know if it's a non-interference engine. The only other thing I can think of is a chunk of carbon not allowing the valve to close all the way.  Grasping at straws here.

[CROSSBOLT]

If the valve timing was off wouldn't the valves hit the piston? I don't know if it's a non-interference engine. The only other thing I can think of is a chunk of carbon not allowing the valve to close all the way.  Grasping at straws here.

Checked the cam timing today and it seemed to be in the correct sequence. I don't think the valves lift enough to touch the piston and there are no marks on it. However, I did find one anomaly in one of the valves. There seems to be an area of no contact on the intake valve seat. I took a felt tip marker to the contact areas of both valves and seats. Exhaust is good but there seems to be about 60 degree arc of no contact. It ranges from 11 to 1 oclock in the picture. On the right of the larger valve seat at about 1 oclock the shiny tapers to black. The tapering at 11 oclock is obscured by poor camera work!
The drill is to get some valve lapping compound tomorrow and lap away the dye marker!