Chrysler Repair: starting problem, plymouth neon, flex plate

Question
I have a 1997 plymouth neon 4cyl.automatic,and I am having trouble with it starting I put in a new battery Iwas told the battery was dead it was about 5 years old,and am still having problems,when I try to start it it sometimes will make a zzzzing sound not like it is cranking but just spinning.I was told that as long as it tries to start it is not the starter.Could you please help me.Thank you.

Answer
Hi Steven,
I am a little confused about the current operation of the starter. Is it the case that sometimes it will start normally, and sometimes it will make a rapid whirring sound but the engine will not crankover and therefor not start?
If it is doing one or the other, then probably what you have is a problem with the mechanical part of the starter motor which is involved with a "Bendix" clutch and  a gear that has to engage with a gear on the flex plate of the engine in order to make the engine actually rotate and start. This if sometimes happens that the starter mounting bolts get loose which prevents the proper connection of the bendix gear with the engine's gear, also it can happen that the bendix gear or the gear on the flex plate become damaged (broken tooth) so that the two will not mesh together reliably. So I would consider this to be a starter problem even though the starter motor is operating properly electrically, because that electrical power must be translated into mecanical motion of the engine thru the gears I have described. Probably the best thing to do is find a reliable mechanic who has some expertise in starter motors and let him figure out why you aren't getting reliable cranking.
If I have mis-understood the behavior of your starter, please let me know what I have gotten wrong and I will try to answer again.
Roland
P.S. If the zzzz sound is a chattering sound, that could mean that the solenoid part of the starter motor is not properly responding to your request for the motor to activate, which is also a matter for a person who works with starter motors. A chattering sound can also occur when the battery is nearly discharged. But if it acts normally a moment later, that would contradict that possibility.
A starter motor is not all that complex, but you have to be willing to get to it and unbolt it, after disconnecting the electrical supply to it. So let me know if you want to try a do-it-yourself repair.