I have a Craftman riding mower with a 22.5HP Briggs & Straton engine Model #331877.My problem is the starter won't spin the engine through the compression stroke. What I have tried or determined so far:
1. The engine will turn until compression.
2. The battery is fully charge.
3. the solenoid is good.
4. I have jumped the mower with a charger and also with a car battery.
5. I have connected the jumper battery neg. directly to the engine and the positive to the starter, to eliminate wiring or solenoid problem
6. I have pulled the fly wheel to determine that the key is not damaged.
7. I have checked the valve adjustment. Intake and exhaust are set to correct spec. (push rods and valves OK. No carbon on piston)
8. Have replaced the starter.
9. New and old starter will spin the engine with the plug out.
10. Removed drive belt to insure there is no drag on the engine.
11. i can easily turn the engine through compression using the palm of my hand on the top of the screen on the flywheel.
12. With the plug out I and my finger over the plug hole the starter won't turn the engine past compression.
13. I have been working on this problem for over a week with now success. I did get the mower started once and it ran fine. Wouldn't turn over again after I shut it off.
I am out of ideas and it's driving me nuts, Any help would be greatly appreciated.
