Small Engines (Lawn Mowers, etc.): Engine Wont Turn Over, compression stroke, valve adjustment

Question
MODEL: 287707
TYPE: 0224-01
CODE: 960808ZD

Here is my problem. When I turn the engine over it spins about half way around and then stops. If I turn the key on and off, it works though and spins about half way again. It's like it stops on the compression stroke. I'v replaced the batter with a new Interstate 290 cca battery and nothing has changed. It almost seems as though the starter don't have enough torque to spin the engine. If I remove the spark plug, the engine turns over great. Whith the plug installed, I can turn it by manualy using 1 hand. But the starter doesn't turn it. I've been told by local small engine repair people the it's my battery and not my starter, well I've replaced the battery so all I'm left with is the starter. Any help?
Thanks in advance
Brian K. Schwab

Answer
Brian, the compression (on the camshaft) release is not working.The valve adjustment may be too high (beyond .004). I suggest they be reset and test. If the engine still stalls the camshaft needs to be  replaced. I believe you can still get warranty if you press the dealer hard enough. Briggs had a problem with this on the model 28's and 31's. Let me know what happens.....bob