2003 Ford Expedition 5.4L V8, 159,280 miles - owned since new

... Every now and then when we turn the key... we get the awful screech sound... Pretty sure it is the flywheel having a few missing teeth.... How aggressive should I be in getting the flywheel replaced assuming it is missing teeth on the flywheel?

I usually quickly replace parts and deal with "issues" quicly but, it happens so infrequently on this issue. And when it does, we just immediately stop cranking, pull the key, put right back in and start up again fine with no issues. The most it ever has done it is twice in one day, but usually it does the screech once every two weeks.

For example, I called my mechanic over two weeks ago and talked to him about it. I asked if I could bring by and replace the starter. That's when he first replied it may be the flywheel and not the starter. Since that call to him, it has made one screech, one time... a few days ago while at the beach. Just pulled the key out, put back in, and started quickly without issue.

Thanks, for any tips,
Todd

 

I'd make sure the starter bolts are tight before anything else

 

Thanks. I always believe with starting with the easiest and least inexpensive thing that may solve it, I will check out the starter bolts. After 15 years, very possible some may have worked slightly loose.

 

How does the engine turn over when the starter kicks in? If it was the flywheel you'd have to move the motor slightly once you were on the striped teeth. It probably a weak starter. I'd start with that after checking the bolts.

 

Beautifully.
So what do you by "move the engine" as in, physically move the engine... if teeth were stripped off the flywheel?

 

Resounding what others have said...inspect the starter- rebuilt/replaced as needed as the Bendix spring may be the culprit...… then definitely inspect the ring gear on the flywheel...if damaged, beyond just a "touch" of wear on a couple of teeth, yes pull the flywheel and replace the ring gear on it. The longer you wait, the worst it will get and more $ it will cost in repairs.

 

My 03 4.6 does the same thing... after repairing battery terminals, checking battery, replacing starter, it's flywheel time for me. I just have to wait for wife to let it go for a day for me to do it. It's hard to even try to find the time to repair when it only does it every couple of days