I have a 1998 250K Timberwolf that ran fine last summer but when trying to start it this spring, it won't turn over fast enough to fire up. Battery, solenoid, starter have been tested, cables are all good but it just won't spin like it used to. Is there some form of automatic compression release (internal) that might be the problem? I've looked at a repair manual online but couldn't reach any conclusions either way. Any suggestions would be much appreciated because I'm stumped.