Westerbeke starter issues

[Leo II]

Hey Y'all,
My starter seems to be jamming into the flywheel. Especially if it's cold and it takes a few cranks to get the engine kicked over.  If I remove the starter motor and reinstall it, that solves the problem temporarily. Is this an alignment issue?  A worn cog on the starter?  Any suggestions on how to troubleshoot this.

[SVJourney]

There are 2 types of starter found on these motors.  One has a long snout, the other is short.  On the long snout starter look for broken springs and galled surfaces on the shaft.  Make sure the gear is not too loose on the shaft. 
Your failure is odd, usually they start spinning before they get to the flywheel which makes a horrible grinding sound or they refuse to release the flywheel and just keep cranking the engine.

To troubleshoot from 1000 miles away, I would say to remove your starter and take it to a rebuilding shop.  For far less than $100 they should be able to clean it up, inspect it and let you know if you need parts.  Lucas parts for the starter are readily available.

If it refuses to engage and spin I would say you have a voltage drop. 
Like a bad ground from the starter to the block.  Consider adding a grounding cable directly from the starter to the negative on the battery.  Test this by using a jumper cable from the starter case to the battery ground and seeing if the starter works normally.
Test the positive voltage feed in much the same way bypassing the starter relay and going directly to the battery.  Be careful doing this!  Its a lot of Amps in a close space.