Grinding noise when starting on 1999 Mercury Cougar

I've replaced the starter, and the key ignition switch. I occasionally hear a grinding noise when I turn the key to start the car - about 1 out of every 25 starts. Usually happens while car has been sitting for several hours. Could this be the fly wheel ? If so, how much does it cost to replace.

Asked by for the 1999 Mercury Cougar
Was it grinding before you replaced the starter, some rebuilt starters have the bare minimum done to them at the rebuild facility and the grinding is usually the starter gear isn't fully engaging the flywheel and could possibly damage the flywheel teeth over time , so if a repair shop installed the starter see if its under warranty, Napa has a labor reimbursement program for the starters they sell not sure about the other auto parts the labor to change the flywheel is 9 hours and the part is $80 and is available at put in your year,make and model then put flywheel in the search box.
OK you must have a section of your flywheel that has bad teeth and about the 25th time you try to start it, the starter gear can't quite engage the worn flywheel teeth. It might last quite a while like this but eventually that spot will wear down too low to engage then the flywheel will have to be replaced.
I see Napa has new starters available #NNE 4n9273 about $200 because rebuilt starters use the same gear over and over a new starter would have fresh gear teeth and maybe engage enough to stop the grinding.
Yes, the grinding noise was worse before I put in a new starter and ignition.
I had the exact same problem, and it was the flywheel. Replaced it and no problems since...
Ok I had flywheel and starter done...still did noise...mechanic replaced starter 4 times..shimmed we have put in FORD flywheel AND starter...and I am crossing my fingers this did it! The fly wheel was only a $20 for the Ford one
Ive had the same problem..5th starter was put in yesterday...12hrs later...grinding and wont start flywheel was put in on the fourth starter..anyone?
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did you ever figure it out. my friend has the same issue? thanks...
I have the same issue with a 2000 cougar with a 2.5 and we tested the electrical resistance, currant, and cleaned the corosion off the housing for a clean seat, and shimming the starter. The starter has been changed several times. The only thing we havent tried is changing the flex plate with a new one. We replaced the flex plate with a used one and had the same problem.