Horrible grinding issue around starter/flywheel

I just replaced the intake gasket/thermostat/radiator cap. Temperature problems solved. Now my truck makes a horrendous metallic grinding noise coming from the starter and fly wheel area. I pulled the starter and testing it by directly hooking it up to the battery. It seems to be working correctly. However, I do see scrape marks on the metal shield around the starter's teeth, but no damage to the actual teeth. What does this mean?
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The starter nose bushing is worn and allowing the starter drive to go too far out causing the grinding noise. Replace the starter and make sure any shims that are required be reinstalled unless new starter directions state do not use them. If you would like, a certified technician from YourMechanic can come to your home or office to replace your starter.

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Causes include the starter not lining up correctly with the ring gear on the flywheel, missing or damaged gear teeth, or a faulty solenoid. Replacing the starter is most often the right solution. However, if there is damage to the ring gear on the flywheel, the ring gear will need to be replaced.
A starter grinding noise means the starter pinion gear is not lining up correctly with the ring gear on the flywheel or flexplate.
When the starter is not properly aligned, when the starter gear extends out to engage with the flywheel, it may create too much contact with the flywheel. In either case, this is noticeable by a very loud grinding sound.
Usually a grinding noise is due to either a worn starter bendix, worn flywheel, the starter coming loose or it needs to be shimmed. But without knowing the type of vehicle all I can do is give you the possibilities. Good luck and hope this helps.
If you notice a rattle or vibration when driving, and the clutch seems to slip in the higher gears, but you do not smell burning friction material, you`re dual mass flywheel is failing.
Does a Bad Battery Affect Your Starter or Alternator? A bad battery won`t usually harm your starter or alternator, however, since both of those components get their voltage directly from the battery, if the battery is underperforming, both the alternator`s and starter`s performance will be affected as well.
When the starter drive gear is worn out or not engaging properly, it will often produce a grinding noise. This is similar to the one that is heard if you start your engine and then accidentally action the ignition switch again. If the grinding symptom is ignored, it may also result in damage to the engine flywheel.
A common cause of grinding noises under your car are failing wheel or hub bearings. Wheel bearings allow the wheel and tire to rotate and are designed for low friction, while hub assemblies have an additional responsibility of securing the wheel and tire to the vehicle.
Yes. If the voltage is too low the starter motor won`t spin up fast enough (accelerate) quickly enough to throw the gear along the bendix. On newer cars it is more complicated, but it still seems likely.
Crankshaft grinding consists of removing a minute amount of finished material from the rod and main journals to rebuild the part back to OEM spec. The full 25 step crankshaft remanufacturing process is quite intensive but is critical to complete engine rebuild.
Electrical connections faulty. Solenoid switch (engaging relay) stiff or faulty. Electric motor damaged electrically.
Loose flywheel or flexplate bolts make a rattling or knocking sound that changes with engine speed. It`s heard behind the engine, where it mounts to the transmission bellhousing.
Remove the starter from the vehicle and energize it with jumper cables to determine if the starter drive is properly moving the pinion gear into the cranking position. If the starter engages and cranks the engine, then skips and spins freely, there are two likely causes: Misalignment of the replacement starter.
One of the symptoms of a bad starter is a clicking noise when you turn the key or push the start button. However, a starter can die without making any sound at all, or it may announce its impending death with whirring and grinding noise—so listen up!
When you attempt to start the vehicle, is there a clicking sound, but it won`t turn over? That may be a good sign. If a jump gets the car running, but won`t turn over again once it`s shut off, a dead battery is likely the cause.
Typically, a new starter will make noise when it`s positioned too close to the ring gear on the flexplate or flywheel. Installing thin, steel shims between the block and starter is the method to eliminate the noise. Another problem that may cause starter noise is an out-of-round flexplate.
If one or more of the flywheel`s teeth are damaged or broken, then the wheel can`t engage with the starter motor. You might need to try a few times to get your car to start, or it might not start at all.
A loose starter can knock teeth off the flywheel. A starter bendix can wear the teeth off the flywheel or make it doesn`t always engage properly. If it doesn`t disengage when the engine is running it can again ruin the teeth. yes a starter can damage the flywheel.

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Horrible grinding issue around starter/flywheel
ANSWER : The starter nose bushing is worn and allowing the starter drive to go too far out causing the grinding noise. Replace the starter and make sure any shims that are required be reinstalled unless new starter directions state do not use them. If you would like, a certified technician from YourMechanic can come to your home or office to replace your starter.

I believe I have an electrical issue. When I turn key the starter doesn’t always spark and it takes a few tries but others it turn
ANSWER : The door lights and radio are on different circuits than the starting system and so faults there would not cause difficulty starting. The flickering of the lights is due to a loose connection somewhere in the circuit and can be diagnosed if you request an electrical component diagnostic. Starters can develop faults in the motor armature leading to intermittent operation (sometimes if you hit the starter with a rubber mallet and then try to start the engine it will work as the armature moves off of the bad spot). If there is no starter operation with the key held in the "start" position, the procedure is to test for power to the starter motor. If there is power (and no voltage drop), but no starter operation, then the starter motor/solenoid assembly is faulty. If there is no power, then the electrical circuit supplying the motor has a fault. That circuit begins at the battery and includes grounds, wiring (some of which is very heavy cabling), fuses, relays, the ignition switch and terminations. Basically, with the key held in the "start" position, the starter is either getting power or it isn’t. With the key in the "start" position, if the starter motor is getting power but it doesn’t work, the starter is condemned and replaced. On the other hand, with the key in the "start" position, if there is no power to the starter, then the circuit is traced until the fault in the circuit is found. In addition to a faulty ignition switch, faults can include high resistances, due to corrosion, wire strand breaks, or loose terminals, which can only be diagnosed using a voltage drop test. If you desire that a certified mechanic resolve this, please simply request a no start diagnostic and the responding certified mechanic will get the problem diagnosed and repaired for you. Please let us know if you have further concerns or questions as we are always here to help you.

I have a 1993 Mitsubishi Mirage. Starter went out and I bought another one an it’s still grinding on the flywheel.
ANSWER : Hi there. The start will need to have shims put in between the starter and the engine block. This will make the start pinion gear line up with the teeth on the flywheel. The pinion gear on the starter is not lining up with the flywheel teeth for the start is too close to the engine block. If you need further assistance with your starter grinding, then seek out a professional, such as one from Your Mechanic, to help you.

Car jerks when accelerating in reverse & makes grinding noise. Is this a transmission or computer issue?
ANSWER : Hi there. Typically when you hear a grinding noise when you move forward or in reverse it’s usually an indication of a gear fault either in the transmission or another driveline component. If this occurs only when in reverse, it’s likely a damaged reverse gear. It is also possible that it’s a hydraulic fluid issue not supplying enough lubrication or pressure inside the lines to fully open the gear. I would recommend having a professional mechanic come to your location and complete a car is hard to shift inspection, so they can diagnose the source of your issue and recommend repairs that should resolve this problem.

Having a starter issue and I have done all the troubleshooting to know it’s the starter. 1997 Ford F150
ANSWER : Hi there – I suspect the "bolt" you mention is on the starter solenoid, which has burned contacts. This means that you can measure voltage to the solenoid, but there is not enough current through the solenoid contacts to kick the starter motor. Jumping it adds enough current to overcome the resistance of the burned contacts. I recommend replacing the starter assembly by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.

Truck suddenly wont start. Starter is good. Been diagnosed with intermittent issue. Need advice. No crank, no start.
ANSWER : Hello, thank you for writing in. These issues can be very frustrating. The first thing to consider is that most automotive parts stores that test starters do not "load test" the starters. This means they test the ability of the starter to spin freely when supplied with power. The tests do not measure its ability to actually push over the engine. This will result in false positives. One way to test this is to test the power at the starter when cranking. If the starter has a full 12 volts to the solenoid (which then creates more power), then the starter has failed. If the starter is not receiving full power, there is another electrical issue going on with the circuit. For more help with diagnostics, contact our service department to schedule an appointment.

Grinding noise when starting engine.
ANSWER : Hi there:

Improper alignment or installation of the starter can cause this grinding noise to occur. However, it’s also possible that internal components inside the starter, the starter relay or the flywheel teeth could also be the source. It’s really difficult to diagnose a noise without physically being there to inspect the vehicle on site, so you should have a mobile mechanic complete a car is making a noise inspection, so they can pinpoint the issue and recommend the right repairs.

I got a F350 Diesel I put a alternator on a new starter a new starter relay and new alternator and the starter stays engaged with
ANSWER : Check the wiring on the starter to the ignition switch and see if they are crossed on the solenoid of the starter. If the wiring is crossed, the starter solenoid will stay engaged as the starter is engaged. If the wiring is hooked up normal, then the ignition switch maybe damaged causing the starter to stay engaged. If you need further assistance with your starter staying engaged, then seek out a professional, such as one from Your Mechanic, to help you.